Selective Oil Separation and Removal Agent, Method for Producing the Same, Method for Selectively Separating and Removing Oil, and Ceramic Porous Body

Abstract

To provide a selective oil separation remover capable of selectively removing an impurity oil floating on a cutting oil diluent and / or contaminating, and to concretely provide the remover capable of preventing contamination of the cutting oil diluent without changing the aspect of the diluent by adsorbing, separating and removing the impurity oil only without adsorbing the oil content included in the diluent.SOLUTION: There are provided a selective oil separation remover including a composite material comprising immobilization of 6-18C alkyl substituent to a porous inorganic material, a production method for the above remover, that remover and a method for selectively separating and removing an oil content using a ceramic porous body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a selective oil separation and removal agent, a method for producing the same, a method for selectively separating and removing oil, and a ceramic porous body. More specifically, the present invention relates to a selective oil separation and removal agent containing a composite material obtained by immobilizing an alkyl substituent having 6 to 18 carbon atoms on a porous inorganic substance, a method for producing the same, and a method for selectively separating and removing oil using the selective oil separation and removal agent. Further, the present invention relates to a ceramic porous body obtained by firing sepiolite having an alkyl substituent having 6 to 18 carbon atoms, which is also applicable to the selective oil separation and removal agent.

Background Art

[0002] In grinding machine tools such as grinding machines for grinding steel materials using a grinding wheel, since the contact point between the grinding wheel and the workpiece becomes very high during grinding, the supply of cutting fluid or grinding fluid is indispensable. As the cutting fluid or grinding fluid, a cutting oil agent dilution obtained by diluting a cutting oil agent is known, and the cutting oil agent dilution includes a coolant liquid having a cooling function. In addition to the lubricating action, the coolant liquid has the action of cooling the processed product, maintaining the sharpness of the grinding wheel well, and maintaining high grinding accuracy. However, in the coolant liquid after use in a grinding machine tool, solid components such as grinding chips (swarf) and abrasive grains (sludge) peeled off from the grinding wheel, and impurity oils such as lubricating oil and rust preventive oil are mixed. Continuing to use such a contaminated coolant liquid will cause a decrease in grinding accuracy and, consequently, a decrease in the processing quality of the workpiece. There are already known grinding machine tools in which a device for separating sludge, impurity oils, etc. mixed in the coolant liquid from the coolant liquid is introduced. However, in a sludge removal facility (Patent Document 1) or a device capable of removing oil such as impurity oils (Patent Document 2), only sludge and floating oil are removed, and it is difficult to remove oil that has not floated, which is not efficient, and the state where impurity oils remain in the coolant liquid is not improved. Also, a coolant liquid sterilization device (Patent Document 3) for sterilizing the coolant liquid to suppress the generation of microorganisms caused by impurity oils is known, but it cannot remove impurity oils. On the one hand, there is a method for treating contaminated coolant liquid (Patent Document 4) in which a flocculant having zeolite as a composition substance is added to the coolant waste liquid for flocculation treatment, the sludge separated from the liquid is removed, and there is also known an oil separation device that separates oil and water by adsorbing oil using an oil adsorbent or the like. However, the flocculant for aggregating oil has no selectivity, removes the oil originally contained in the coolant liquid, and the treated coolant liquid cannot be reused. Further, although the coolant liquid is a mixture of water, oil, and a surfactant, an oil separation device that clearly separates water and oil also removes the emulsified oil originally contained in the coolant liquid, causing a deterioration in the performance of the coolant liquid. For these reasons, there is a need for a separation method and an adsorbent that target the impurity oil floating or mixed in the coolant liquid without deteriorating the performance of the coolant liquid and without removing the oil content of the coolant liquid.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0004] One object of the present invention is to provide an efficient means for removing oil present on the surface of a diluted cutting fluid and / or mixed in the diluted cutting fluid. More specifically, without removing the oil contained in the diluted cutting fluid, the oil present on the surface and / or mixed in is selectively adsorbed, separated, and removed, thereby surely suppressing a decrease in the performance of the diluted cutting fluid due to the oil without changing the properties of the diluted cutting fluid. Another object of the present invention is to provide a novel ceramic porous body that can also be used for separating the oil. A further object of the present invention is to provide a means for removing impurities such as oil and contaminants floating on and / or mixed in a liquid, which has excellent adsorptivity.

Means for Solving the Problems

[0005] To solve the above problems, the present inventors have conducted intensive research. As a result, a selective oil separation and removal agent containing a composite material in which an alkyl substituent having 6 to 18 carbon atoms is immobilized on a porous inorganic substance does not remove the oil originally contained in the diluted cutting fluid, and is a substance that degrades the performance of the diluted cutting fluid. It was discovered that the oil present on the surface of the diluted cutting fluid and / or mixed in the diluted cutting fluid can be selectively separated and removed, leading to the present invention. Furthermore, since the composite material (ceramic porous body) has a high adsorptivity to oil, the present inventors discovered that the composite material is useful as a general means for removing oil and may also be useful as a means for removing contaminants such as organic substances mixed in a liquid. Specifically, the present invention can be in the following aspects. 〔1〕A selective oil separation and removal agent containing a composite material in which an alkyl substituent having 6 to 18 carbon atoms is immobilized on a porous inorganic substance. 〔2〕The selective oil separation and removal agent according to 〔1〕, wherein the alkyl substituent is bonded to the porous inorganic substance via a silicon atom. 〔3〕The selective oil separation and removal agent according to the above-mentioned 〔1〕 or 〔2〕, wherein the porous inorganic substance is a crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms, and titanium atoms. 〔4〕The selective oil separation and removal agent according to the above-mentioned 〔3〕, wherein the crystalline compound is selected from the group consisting of zeolite, bentonite, acid clay, activated clay, attapulgite, sepiolite, cristobalite, sericite, pumice, vermiculite, perlite, and diatomaceous earth. 〔5〕The selective oil separation and removal agent according to the above-mentioned 〔3〕, wherein the crystalline compound is zeolite, and the atomic ratio of Si / Al in the zeolite is 0.1 to 100. 〔6〕The selective oil separation and removal agent according to the above-mentioned 〔3〕, wherein the crystalline compound is zeolite with a structure code of FAU. 〔7〕The selective oil separation and removal agent according to the above-mentioned 〔3〕, wherein the crystalline compound is sepiolite, and the atomic ratio of Si / Mg in the sepiolite is 0.1 to 100. 〔8〕The selective oil separation and removal agent according to any one of the above-mentioned 〔1〕 to 〔7〕, wherein the alkyl substituent has 8 to 18 carbon atoms. 〔9〕The selective oil separation and removal agent according to any one of the above-mentioned 〔1〕 to 〔8〕, wherein the selective oil separation and removal by the selective oil separation and removal agent is the separation and removal of the oil component by selective adsorption of the oil component present on the surface of the cutting oil diluent and / or mixed in the cutting oil diluent from the cutting oil diluent. 〔10〕The selective oil separation and removal agent according to the above-mentioned 〔9〕, wherein the cutting oil diluent is a water-soluble coolant. 〔11〕The selective oil separation and removal agent according to the above-mentioned 〔10〕, wherein the coolant is an emulsion. 〔12〕The selective oil separation and removal agent according to any one of the above-mentioned 〔9〕 to 〔11〕, wherein the Snyder's polarity parameter of the oil component is 10.0 or less. 〔13〕The selective oil separation and removal agent according to any one of the above-mentioned 〔9〕 to 〔12〕, wherein the polarity of the oil component is smaller than the polarity of the cutting oil diluent. A method for selectively separating and removing oil components present on the surface of a diluted cutting fluid and / or mixed in the diluted cutting fluid, comprising: mixing the diluted cutting fluid in which the oil components are present on the surface and / or mixed with the selective oil component separation and removal agent according to any one of [1] to

[13] ; stirring the diluted cutting fluid to adsorb the oil components onto the selective oil component separation and removal agent; and separating and removing the selective oil component separation and removal agent adsorbed with the oil components from the diluted cutting fluid. A method for selectively separating and removing oil components present on the surface of a diluted cutting fluid and / or mixed in the diluted cutting fluid, comprising the above steps. 〔15〕(1) A step of preparing a porous inorganic substance which is a crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms and titanium atoms; (2) A step of preparing a silane coupling agent having an alkyl substituent having 6 to 18 carbon atoms; (3) A step of mixing the porous inorganic substance and the silane coupling agent; and (4) A step of firing the mixture in air or an oxidizing atmosphere. A method for producing the selective oil component separation and removal agent according to any one of [2] to

[13] , comprising the above steps. 〔16〕A ceramic porous body having an alkyl substituent having 6 to 18 carbon atoms and obtained by firing sepiolite. 〔17〕 The ceramic porous body according to

[16] , wherein the alkyl substituent is bonded to the sepiolite via a silicon atom. 〔18〕 The ceramic porous body according to

[16] or

[17] , wherein the atomic ratio of Si / Mg in the sepiolite is 0.1 to 100.

Advantages of the Invention

[0006] According to the present invention, without removing the oil content contained in the cutting oil diluent, selectively adsorbing, separating, and removing the oil present on the surface of the cutting oil diluent and / or mixed in the cutting oil diluent, it is possible to surely suppress the deterioration of the performance of the cutting oil diluent due to the oil content without changing the properties of the cutting oil diluent. In addition, the present invention can provide a method for producing a selective oil separation and removal agent having the above characteristics, and a method for selectively separating and removing oil using the selective oil separation and removal agent. Further, according to the present invention, it is possible to provide a novel composite material (ceramic porous body) that can generally remove oil and also remove impurities such as other contaminants.

Brief Description of Drawings

[0007]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0008] [Selective Oil Separation and Removal Agent] One aspect of the present invention is a selective oil separation and removal agent containing a composite material obtained by immobilizing an alkyl substituent having 6 to 18 carbon atoms on a porous inorganic substance. More specifically, in the present invention, the composite material in which the alkyl substituent imparting oil selectivity is immobilized or compounded with the porous inorganic substance that adsorbs oil, more precisely, an organic-inorganic composite material, is present on the surface of the cutting oil diluent and / or selectively adsorbs the oil mixed in the cutting oil diluent, thereby having the property of separating and removing the oil. In the present specification, "selectively adsorb" means, for example, that the selective separation and removal agent of the present invention selectively attracts, adheres to, or takes in a specific oil by physical adsorption force such as van der Waals force or chemical adsorption force such as covalent bond. Further, "separation" means, for example, separating or dissociating the cutting oil diluent from the oil present on the surface of the cutting oil diluent and / or mixed in the cutting oil diluent. Further, "removal" means, for example, recovering, removing, or eliminating the oil separated from the cutting oil diluent from the cutting oil diluent. In addition, the preferred embodiments, more preferred embodiments, etc. exemplified below can be used in appropriate combinations with each other regardless of the expressions such as "preferred" and "more preferred". Further, the description of the numerical range is illustrative, and ranges appropriately combined with the upper and lower limits of each range and the numerical values of the examples can also be preferably used. Furthermore, terms such as "containing" or "including" may be read as "consisting essentially of" or "consisting only of". The selective oil separation and removal agent will be described in detail below.

[0009] [Porous Inorganic Substance] The porous inorganic material of the present invention preferably has an alkyl substituent having 6 to 18 carbon atoms immobilized on its surface and / or in its pores, and forms a composite material (ceramic porous body) together with the alkyl substituent. In the present invention, the porous inorganic material may be a crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms, and titanium atoms. Examples of the crystalline compound include zeolite (synthetic zeolite, natural zeolite), bentonite, acid clay, activated clay, attapulgite, sepiolite (synthetic sepiolite, natural sepiolite), cristobalite, sericite, pumice, vermiculite, perlite, and diatomaceous earth. As the crystalline compound, at least one selected from the group consisting of synthetic zeolite, natural zeolite, synthetic sepiolite, and natural sepiolite can be preferably selected, and more preferably synthetic zeolite and natural sepiolite. Here, when the crystalline compound is zeolite, the Si / Al atomic ratio of silicon dioxide and aluminum oxide in the crystalline compound is, for example, 0.1 to 200, preferably 0.1 to 100, and more preferably 2 to 6. When the crystalline compound is sepiolite, the Si / Mg atomic ratio of silicon dioxide and magnesium oxide in the crystalline compound is, for example, 0.1 to 200, preferably 0.1 to 100, and more preferably 1 to 5. In addition to silicon dioxide, aluminum oxide, and magnesium oxide, other metals or metal compounds may be contained in the crystalline compound. The metal in the other metal or metal compound is a metal atom selected from Groups 4A to 7A, 8, and 1B to 3B, and more preferably Ag, Cu, Zn, and Sn. Examples of the metal compound include oxides, nitrides, carbides, and borides. The mass ratio of the other metal or metal compound contained in the binding compound may be 0.1 to 30% by mass, preferably 1 to 20% by mass, based on 100% by mass of the crystalline compound.

[0010] Here, "zeolite" is a crystalline aluminosilicate containing silicon dioxide (silica) and / or aluminum oxide (alumina), and is a porous crystal also called an oxide ceramic-based porous material. Generally, the basic unit of the crystal structure (also referred to as the framework structure) of zeolite is a tetrahedron composed of four oxygen atoms surrounding a silicon atom or an aluminum atom (TO4 tetrahedral structure, where T is Si and / or Al), and these are connected in three-dimensional directions to form a crystal structure. The general composition of zeolite is represented by the following formula (I): M z+ [(SiO2) x (Al2O3) y z- (I) (In formula (I), M is a cation species capable of ion exchange, usually representing a monovalent or divalent metal, z is the valence of M, and x and y are arbitrary integers) and can be shown as. Preferably, M is a metal atom selected from Groups 1A to 7A, 8, and 1B to 3B, more preferably hydrogen ion, lithium ion, calcium ion, sodium ion, potassium ion, magnesium ion, and barium ion, and x / y (SiO2 / Al2O3 molar ratio) is, for example, 0.1 to 200, preferably 1 to 100, more preferably 2 to 6. It should be noted that the zeolite represented by the above formula (I) may also be expressed as a general formula further including hydrates.

[0011] ​The crystal structure of the zeolite that can be used in the present invention is not particularly limited. For example, various crystal structures represented by the three-letter structure codes defined by the International Zeolite Association can be mentioned. Examples of the structure codes include, for example, the structure codes of LTA, FER, MWW, MFI, MOR, LTL, FAU, and BEA. Also, when a preferred embodiment of the crystal structure used in the present invention is indicated by the name of the crystal structure, it is preferably at least one selected from the group consisting of A-type, X-type, β-type, Y-type, L-type, ZSM-5 type, MCM-22 type, ferrierite type, and mordenite type, more preferably at least one selected from the group consisting of A-type, X-type, and Y-type, and still more preferably X-type or Y-type. The chemical structural formula showing the skeleton of a general LTA-type zeolite is shown in FIG. 1, and the skeleton structure thereof is shown in FIG. 2, respectively. Generally, synthetic zeolite has cations in its crystal structure, and the cations compensate for the negative charges in the crystal structure composed of aluminosilicate to make up for the deficiency of positive charges.

[0012] The zeolite that can be used in the present invention is not particularly limited, but as the cation, preferably, a zeolite containing at least one selected from the group consisting of hydrogen ion, lithium ion, calcium ion, sodium ion, potassium ion, magnesium ion, and barium ion may be used. More preferably, as the cation, a zeolite containing at least one selected from the group consisting of hydrogen ion, lithium ion, calcium ion, sodium ion, and potassium ion, and still more preferably a zeolite containing at least one selected from the group consisting of hydrogen ion, calcium ion, and sodium ion may be used. Also, those in which all or part of the silicon element in the zeolite skeleton is replaced with other elements such as phosphorus (P), and those in which all or part of the aluminum element in the zeolite skeleton is replaced with other elements such as boron (B), gallium (Ga), and titanium (Ti) may be used.

[0013] Zeolites have unique pore diameters, surface electric fields, ion exchange capabilities, solid acid properties, adsorption capabilities, etc., and are used in applications such as desiccants, adsorbents, molecular sieve type separators, ion exchangers, and catalysts. The pore diameter of the zeolite used here (measured by the gas adsorption method) is, for example, 0.01 to 100 Å, preferably 0.1 to 50 Å, and more preferably 1 to 10 Å. When using zeolite powder, the average particle size of the zeolite, when measured by the d50% median diameter and the laser diffraction / scattering method, is, for example, 0.01 to 100 μm, preferably 0.1 to 50 μm, and more preferably 1 to 10 μm.

[0014] "Sepiolite" is a clay mineral mainly composed of hydrated magnesium silicate, and is a porous crystal of monoclinic or orthorhombic system showing a fibrous form. Sepiolite has a chain crystal structure formed by layers of a two-dimensional crystal structure of 2:1 type layer SiO tetrahedral sheets like talc, stacked alternately like bricks, and continuous channels are formed by the voids opened on the particle surface being connected in a network inside the particles. Since sepiolite has silanol groups, it shows adsorptivity due to hydrogen bonding with moisture and organic compounds, and has the performance of absorbing 150% of its own weight of moisture. The composition of sepiolite is, for example, the following formula (II) or (III): Mg8Si 12 O 30 (OH)4(OH2)4·8H2O (II) Mg9Si 12 O 30 (OH)6(OH2)4·6H2O (III) (In formulas (II) and (III), (OH)4 is crystal water, (OH2)4 is bound water, and 6 - 8H2O is adsorbed water) It can be shown by . The content of SiO2 per unit crystal structure is, for example, 40 to 70%, preferably 50 to 60%, more preferably 54 to 60%. The content of MgO per unit crystal structure is, for example, 1 to 50%, preferably 10 to 40%, more preferably 20 to 30%, and even more preferably 22 to 28%. The Si / Mg molar ratio per unit crystal structure is, for example, 0.1 to 200, preferably 0.1 to 100, more preferably 1 to 5. Sepiolite may further contain crystalline silica (quartz), aluminum oxide (Al2O3), iron oxide (Fe2O3), calcium oxide (CaO), potassium oxide (K2O), sodium oxide (Na2O), manganese oxide (MnO), titanium dioxide (TiO2), etc.

[0015] Sepiolite occurs naturally associated with limestone, dolomite, serpentine, etc., and may also be synthesized from magnesium compounds and silicon compounds as raw materials. Sepiolite generally exhibits a white color, and may also be an opaque color with varying degrees of gray, yellow, and black mixed. Depending on the origin, sepiolite includes α-type long fibers with a high crystallinity and a distinct fibrous form, and β-type short fibers with a low crystallinity and a massive or clay-like form. The chemical composition of β-type sepiolite differs from that of α-type sepiolite in that it has a higher H2O content. Also, in X-ray analysis, β-type sepiolite has the characteristics of having fewer diffraction lines and wider diffraction line widths compared to α-type sepiolite. In the present invention, either α-type or β-type sepiolite can be used.

[0016] The wire diameter (fiber diameter) of the sepiolite used here (measured by the mercury intrusion method) has an average wire diameter of, for example, 0.001 to 1 μm, preferably 0.005 to 0.1 μm, more preferably 0.01 to 0.1 μm. The specific surface area of sepiolite is, for example, 100 to 500 m 2 / g, preferably 150 to 400 m 2 / g, more preferably 200 to 300 m 2 / g. The Mohs hardness of sepiolite is, for example, 1 to 5, preferably 1.5 to 3, more preferably 2 to 2.5. The specific gravity of sepiolite is, for example, 1.0 to 3.0 g / cm 3 and preferably 1.5 to 2.5 g / cm 3 .

[0017] The porous inorganic material of the present invention may be formed into a molded body by binder granulation of zeolite or sepiolite. The binder is not particularly limited, and any material suitable for assisting the granulation of the porous inorganic material can be used. The addition amount of the binder may be appropriately adjusted to an amount that enables granulation. Binder materials include organic materials and inorganic materials. Examples of organic materials include dextrin, carboxymethyl cellulose, hydroxyethyl cellulose, xanthan gum, acrylic resin, polystyrene, polyvinyl alcohol, and carboxyvinyl polymer. Examples of inorganic materials include bentonite, sepiolite, smectite, silica, and diatomaceous earth. A more specific method for producing the porous inorganic material of the present invention is as described below.

[0018] The pore diameter of the porous inorganic material (measured by the gas adsorption method) is, for example, 0.01 to 100 Å, preferably 0.1 to 50 Å, more preferably 1 to 10 Å. Further, the porous inorganic material preferably has a three-dimensional network structure and includes (a) an oxide-based ceramic layer formed on part or all of the surface and (b) a non-oxide-based ceramic portion formed on a portion other than the ceramic layer. In particular, it is preferable that the pores in the porous inorganic material are through-holes (communication holes). Furthermore, the average particle diameter of the porous inorganic material of the present invention is, for example, 0.01 μm to 100 mm, preferably 0.1 to 50 mm, more preferably 1 μm to 10 mm when measured by the d50% median diameter and the laser diffraction / scattering method.

[0019] Examples of other additives contained in the porous inorganic material of the present invention include end-capping agents such as trimethylchlorosilane, trimethylmethoxysilane, trimethylethoxysilane, and hexamethyldisilazane. Other additives may be bonded to the surface of the porous inorganic material of the present invention, the inner part of the pores, and the like.

[0020] [Alkyl substituent] In the present invention, the alkyl substituent having 6 to 18 carbon atoms in the composite material contained in the selective oil separation and removal agent is a side chain immobilized on the above-mentioned porous inorganic material. Although the number of carbon atoms is 6 to 18, further, for example, 8 to 18 carbon atoms are preferable, 12 to 18 carbon atoms are more preferable, and 18 carbon atoms are particularly preferable. As the alkyl substituent, as long as the number of carbon atoms is 6 to 18, it may be a straight chain or a branched chain, saturated or unsaturated, and may further have a halogen, a cyclohexyl group, or a phenyl group as a substituent, but a straight-chain alkyl substituent having no further substituent is preferable.

[0021] The alkyl substituent having 6 to 18 carbon atoms is immobilized on the surface and / or inside the pores of the above-mentioned porous inorganic material. Without being bound by theory, the immobilization referred to here means that the alkyl substituent having 6 to 18 carbon atoms as an organic material is chemically or physically immobilized on the surface and / or inside the pores of the porous inorganic material as an inorganic material. More specifically, it is considered that the alkyl substituent having 6 to 18 carbon atoms is chemically or physically immobilized on the surface and / or inside the pores of a porous inorganic material such as zeolite or sepiolite. The chemical immobilization referred to here includes, for example, covalent bonds and the like. The physical immobilization referred to here includes generally known physical adsorption, for example, adsorption by van der Waals force.

[0022] When the alkyl substituent is preferably immobilized on the porous inorganic substance by a bond through the silicon atom of the porous inorganic substance. Specifically, it is preferable that the alkyl substituent binds by binding a silicon-containing compound or the like to a hydroxyl group (unreacted portion) in the porous inorganic substance. As the silicon-containing compound, a silane coupling agent having an alkyl chain with 6 to 18 carbon atoms is preferable. For example, chemical formula (IV): R 1 -Si-(R 2 ) 4-n (R 3 ) n-1 (IV) (In formula (IV), R 1 is a monovalent alkyl group having 6 to 18 carbon atoms, which is linear or branched, saturated or unsaturated, preferably a linear and unsaturated alkyl group having 6 to 18 carbon atoms, or 8 to 18 carbon atoms, or 12 to 18 carbon atoms; R 2 is each independently a monovalent alkoxy group or a halogen group having 1 to 2 carbon atoms, preferably any one of chloro (Cl) groups; R 3 is each independently either hydrogen or a methyl group; and n is 1 to 3, preferably 1 to 2.) can be a compound represented by. As the silicon-containing compound, more preferably, a silane coupling agent having an alkyl chain with 8 carbon atoms as follows can be mentioned. TIFF0007713700000001.tif26120 (Example of a silane coupling agent with 8 carbon atoms)

[0023] [Composite material] A further aspect of the present invention is a composite material (ceramic porous body) having an alkyl substituent with 6 to 18 carbon atoms on a porous inorganic substance. The composite material of the present invention is a composite of the above-mentioned porous inorganic substance and an alkyl substituent having 6 to 18 carbon atoms, and preferably, the alkyl substituent having 6 to 18 carbon atoms can be a composite in a state fixed to the porous inorganic substance. Preferably, the composite material of the present invention is an organic-inorganic composite material in a state where an alkyl substituent having 6 to 18 carbon atoms that imparts selectivity to oil is immobilized or compounded on the surface and / or inside the pores of a porous inorganic substance having a function of adsorbing oil on its surface and / or inside the pores, and has a function of selectively separating and removing oil. Without being bound by theory, the composite material of the present invention is considered to have the ability to adsorb to oil mainly by taking in oil into the porous portion of the porous inorganic substance. Using the composite material of the present invention, it is also considered possible to remove not only a liquid containing a predetermined oil such as a coolant liquid but also oil floating or mixed in a liquid not containing oil, that is, to perform general oil removal regardless of whether it is selective or non-selective. Further, it is suggested that impurities such as organic substances floating or mixed in the liquid are naturally taken into and removed from the porous portion along with the adsorption of oil by the composite material when they are in an adherent state with oil. Examples of the composite material of the present invention include a ceramic porous body having an alkyl substituent having 6 to 18 carbon atoms and obtained by firing sepiolite.

[0024] [Oil selectively separated and removed] Hereinafter, the oil selectively separated and removed by the selective oil separation and removal agent of the present invention will be described in detail. The oil selectively separated and removed in this specification (hereinafter also referred to as impurity oil) is oil present on the surface of a cutting oil agent diluent described later and / or mixed in the cutting oil agent diluent, and is adsorbed selectively by the selective oil separation and removal agent of the present invention, thereby separated and removed from the cutting oil agent diluent. As used herein, "present on the surface of the cutting fluid diluent" may mean, for example, a state in which the oil component floats on the surface of the cutting fluid diluent without mixing with the cutting fluid diluent. Further, "mixed into the cutting fluid diluent" may mean, for example, a state in which the oil component is mixed into the cutting fluid diluent by stirring or the like, but is dispersed without emulsifying with the cutting fluid diluent. The impurity oil is preferably an oil component having a polarity smaller than that of the cutting fluid diluent described later. The Snyder polarity parameter of the impurity is, for example, 0.1 to 10.0, preferably 0.1 to 6.9, and more preferably 0.1 to 5.1. The Snyder polarity parameter refers to the value described in Table 6.1 (Properties of solvents for use in liquid chromatography) on pages 248 to 250 of "Introduction to Modern Liquid Chromatography, 2nd Edition" written by L.R. Snyder et al. The impurity oil may be the same oil component as the oils such as the base oil contained in the cutting fluid diluent described later, or may be a different oil component. It follows the values described in Table 6.1 (Properties of solvents for use in liquid chromatography) on pages 248 to 250 of "Introduction to Modern Liquid Chromatography, 2nd Edition" written by L.R. Snyder et al. Examples of the impurity oil include mineral oil, synthetic ester, animal and vegetable fats and oils, α-olefin, normal paraffin, isoparaffin, and polyoxyalkylene glycol. The impurity oil may be a combination of two or more of these. Further, the impurity oil is usually a liquid, but may be a slurry-like contaminant in which metal ions are dissolved or sludge is suspended in the liquid.

[0025] Examples of mineral oils include those obtained by distilling petroleum and having undergone processes such as hydrogenation and reforming. Mineral oils may be a combination of two or more of these. Examples of synthetic esters include methyl laurate, methyl oleate, neopentyl glycol dioleate, trimethylolpropane trioleate, and pentaerythritol tetraoleate. The number of carbon atoms in the fatty acids of these synthetic esters is, for example, 4 to 28, and they can have any degree of unsaturation and branched structure. Synthetic esters may be a combination of two or more of these. Examples of animal and vegetable fats and oils include animal fats such as lard, tallow, mutton fat, and fish oil, and vegetable fats such as rapeseed oil, soybean oil, coconut oil, and palm oil. Animal and vegetable fats and oils may be a combination of two or more of these. α-olefins, normal paraffins, and isoparaffins can have any structure and number of carbon atoms. Polyoxyalkylene glycols can have any molecular weight and number of moles of alkylene glycol added. One or more ends of the polyoxyalkylene glycol can be an alkyl group, alkenyl group, or alkyl group having a substituent, and the terminal group and the alkenyl group can be linked by a bond such as an ether, ester, or amide. Polyoxyalkylene glycols may be a combination of two or more of these.

[0026] [Cutting oil diluent] The cutting oil diluent will be described in detail below. The cutting oil agent in this specification can be used, for example, to suppress friction between a grinding wheel and a workpiece during grinding in a grinding machine using a grinding wheel, and the cutting oil diluent can mean a liquid obtained by diluting the cutting oil agent with water. Specifically, the cutting oil diluent can be used, for example, in cutting, grinding, cutting, polishing, gear cutting and tapping, and plastic processing such as rolling, drawing, pressing, forging and roll forming. The cutting oil diluent may include those having a cooling action in addition to a lubricating action (hereinafter referred to as coolant liquid). Examples of the coolant liquid in this specification include, but are not limited to, liquids obtained by diluting water-soluble cutting oil agents defined as types A1, A2, and A3 in JIS K 2241. The cutting oil diluent preferably has a polarity greater than that of the impurity oil. The Snyder polarity parameter of the cutting oil diluent is preferably 3.9 to 10.2, more preferably 5.1 to 10.2.

[0027] The cutting oil diluent is a liquid in an emulsion state obtained by diluting a cutting oil agent containing, as a base oil, a single substance or a mixture of oils such as animal and vegetable fats and oils, mineral oils, and esters, and further containing various additives such as surfactants, rust inhibitors, oiliness improvers, extreme pressure additives, defoamers, coupling agents, preservatives, bactericides, inorganic salts, and antioxidants, with water to about 0.2 to 20% by volume, and emulsifying oils such as the base oil. The oils such as the base oil contained in the cutting oil diluent may be the same oil as the impurity oil or different oils.

[0028] The composition of the cutting oil diluent is, for example, base oil: 10 - 90%, surfactant: 1 - 20%, rust inhibitor: 0 - 30%, oiliness improver: 0 - 30%, extreme pressure additive: 0 - 30%, defoamer: 0 - 5%, coupling agent: 0 - 5%, preservative: 0 - 5%, bactericide: 0 - 5%, inorganic salts: 0 - 30%, antioxidant: 0 - 5%, water: 10 - 70%.

[0029] Examples of the base oil include polyolefin oil, polyolefin oil, diester oil, hindered ester oil, ethylene glycol, liquid polyethylene glycol, polybutene, turbine oil, machine oil, spindle oil, paraffinic, naphthenic, and aromatic mineral oils, etc. Examples of the surfactant include alkyl sulfates as anionic surfactants, aminoacetic acid betaine, fatty acid soap, naphthenic acid soap, sorbitan ester, and alkylolamide as amphoteric surfactants, and alkyl glucoside, polyoxyalkylene hydrogenated castor oil, polyoxyethylene alkyl ether, and carboxylic acid alkanolamide as nonionic hydrocarbon surfactants, etc. Examples of the rust inhibitor include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, dicarboxylic acids, silicate, phosphate, borate, molybdate, etc. Examples of the oiliness improver include animal and vegetable oils, ester oils, and long-chain fatty acids (e.g., octylic acid, lauric acid, palmitic acid, oleic acid, stearic acid, etc.), and esters composed of long-chain fatty acids and monohydric and polyhydric alcohols, or amides composed of alkylamines, etc. Examples of the extreme pressure additive include chlorinated paraffin, sulfurized fatty oil, etc., and zinc dioctyldithiophosphate, dilauryl dipropionate, etc. Examples of the defoamer include silicone defoamers, organic defoamers, etc. Examples of the coupling agent include glycol, etc. Examples of the preservative include triazine compounds, etc. Examples of the antioxidant include sodium metasilicate, sodium orthosilicate, carboxybenzotriazole, mercaptobenzothiazole, etc.

[0030] [Properties of the Selective Oil Separation and Removal Agent] The selective oil separation and removal agent of the present invention has the property of efficiently adsorbing, separating, and removing the impurity oil present on the surface of the cutting fluid diluent and / or the impurity oil mixed into the cutting fluid diluent and dispersed in the cutting fluid diluent by stirring or the like. Since the selective oil separation and removal agent of the present invention does not adsorb components such as base oil originally contained in the cutting fluid diluent such as coolant liquid, it does not change the properties of the cutting fluid diluent. Since the selective oil separation and removal agent selectively adsorbs the impurity oil floating on and / or mixed into the cutting fluid diluent, the impurity oil can be separated and removed by recovering the selective oil separation and removal agent adsorbed with the impurity oil.

[0031] Although not bound by theory, it is considered that the selective oil separation and removal agent of the present invention mainly takes in contaminants such as impurity oil into the porous part of the porous inorganic substance in the composite material. Specifically, porous inorganic substances such as zeolite and sepiolite of the present invention can adsorb specific components, that is, impurity oil, by immobilizing an alkyl substituent having 6 to 18 carbon atoms on the surface and / or in the pores of the porous part and changing the polarity of the porous inorganic substance. On the other hand, the selective oil separation and removal agent of the present invention does not take in the oil originally contained in the cutting fluid diluent and present in an emulsified state. The oils emulsified in the cutting fluid diluent change their polarity by forming an emulsion. The oils forming the emulsion are considered to be less hydrophobic than the alkyl substituents having 6 to 18 carbon atoms in the composite material contained in the selective oil separation and removal agent, so the alkyl substituents do not attract the oils forming the emulsion. Therefore, since the porous inorganic substance does not take in the oils, the selective oil separation and removal agent is considered not to adsorb the oil in the cutting fluid diluent.

[0032] Here, it can be confirmed that the selective oil separation and removal agent does not adsorb the components in the cutting fluid dilution by observing the change in the properties of the cutting fluid dilution. The properties of the cutting fluid dilution can be confirmed by the decrease in viscosity or the change in color from the appearance. As described above, since the cutting fluid dilution is a liquid in an emulsion state containing oil and water, it exhibits a milky white (white opaque) color, or a colored opaque color when the cutting fluid dilution is colored. When the oil in the cutting fluid dilution is removed together with the impurity oil, it is no longer in an emulsion state, so the color of the cutting fluid dilution changes from milky white to transparent (from colored opaque to colored transparent when colored), and at the same time the viscosity also decreases. On the other hand, when only the impurity oil is selectively removed, the color and viscosity do not change.

[0033] In addition, the ability of the selective oil separation and removal agent to adsorb impurity oils such as those floating or mixed in the cutting fluid dilution can be evaluated by the adsorption amount of the impurity oil. The adsorption amount can be, for example, adding oil such as lubricating oil as the impurity oil to a predetermined amount of the selective oil separation and removal agent (for example, 0.5 g), and when the adsorption of the oil such as lubricating oil to the porous part is completed, for example, when the selective oil separation and removal agent is dispersed without aggregating in the added lubricating oil, the amount of lubricating oil added at that time can be used as an index of the adsorption amount. For example, it is preferable that the mass of the added oil (index of the adsorption amount) is 0.05 g or more, more preferably 0.1 g or more, and even more preferably 0.3 g or more with respect to 0.5 g of the selective oil separation and removal agent of the present invention. There is no particular need to define the upper limit of the index of the adsorption amount, but it is usually about 0.5 g, and it may be 0.3 g or less. The preferable range of the index of the adsorption amount can be a combination of these lower and upper limits.

[0034] In addition, the selective oil separation and removal agent of the present invention has the property of selectively adsorbing only the impurity oils that float or mix in, separating and removing them, and then aggregating to form a solid mass, and has the property of being able to easily remove the aggregated selective oil separation and removal agent. Thereby, the impurity oil can be surely adsorbed, separated, and removed, and the deterioration of the cutting fluid dilution can be prevented. When recovering impurity oils such as lubricating oils that float or mix into a cutting oil diluent such as a coolant liquid, the selective oil separation and removal agent does not adsorb the components of the coolant liquid, but only adsorbs the lubricating oil and forms an aggregated mass. This aggregated mass is filtered together with the coolant liquid, and the fact that the lubricating oil has been selectively adsorbed can be confirmed by observing the properties of the coolant liquid and measuring the volume of the selective oil separation and removal agent separated from the coolant liquid by filtration and comparing it with the volume of the selective oil separation and removal agent initially added. As for the result, it is preferable that the properties of the coolant liquid do not change, and the volume of the lubricating oil removed from the coolant liquid is 10% by volume or more, more preferably 30% by volume or more, still more preferably 50% by volume or more, particularly preferably 80% by volume or more, and most preferably 90% by volume or more, with respect to the volume of the lubricating oil initially added. The upper limit of the volume ratio is preferably 100% by volume, but it may be 90% by volume or less, or 80% by volume or less. The preferable range of the volume ratio can be a combination of these lower and upper limits.

[0035] [Use of the selective oil separation and removal agent] The selective oil separation and removal agent of the present invention is useful as a composition for purifying or preventing contamination of a cutting oil diluent such as a contaminated coolant liquid. In particular, it is useful as a composition capable of adsorbing, separating, and removing impurity oils that float or mix on the surface of the cutting oil diluent. Also, as described above, the selective oil separation and removal agent of the present invention selectively takes in specific components such as impurity oils, while not taking in the oil content of the cutting oil diluent. Therefore, since the quality of the cutting oil diluent is not impaired, the cutting oil diluent after contamination removal can be reused.

[0036] [Selective oil separation and removal method] The method for selectively separating and removing oil present on the surface of a cutting oil diluent and / or mixed in the cutting oil diluent using the selective oil separation and removal agent of the present invention includes at least the following steps: (1) A step of mixing the selective oil separation and removal agent into the cutting oil diluent in which the oil is present on the surface and / or mixed in. (2) Stir the cutting oil diluent to adsorb the oil component onto the selective oil separation and removal agent, and (3) Remove the selective oil separation and removal agent adsorbed with the oil component from the cutting oil diluent are included.

[0037] [Method for producing selective oil separation and removal agent] The method for producing the selective oil separation and removal agent of the present invention includes at least the following steps: (A) A step of mixing a porous inorganic substance and an alkyl substituent having 6 to 18 carbon atoms, (B) A step of firing the mixture in air or an oxidizing atmosphere, are included. For example, when the composite material of the present invention is formed by bonding an alkyl substituent having 6 to 18 carbon atoms to a porous inorganic substance via a silicon atom, the method for producing a selective oil separation and removal agent containing the composite material includes the following steps: (1) A step of preparing a porous inorganic substance which is a crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms and titanium atoms, (2) A step of preparing a silane coupling agent having an alkyl substituent having 6 to 18 carbon atoms, and (3) A step of mixing the porous inorganic substance and the silane coupling agent, and (4) A step of firing the mixture in air or an oxidizing atmosphere, are included. Here, the details of the "silane coupling agent" and the "crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms and titanium atoms" are as described above. These mixtures can utilize mixers and mills, etc. Hereinafter, the method for producing the selective oil separation and removal agent by steps (1) to (4) will be described in detail.

[0038] The mixture obtained above may be further shaped into a shaped body before firing. Here, the shaping method of the above-mentioned shaped body can be carried out according to a known ceramics shaping method such as the method described in JP-A-2003-55063. For example, shaping methods such as press molding, casting molding, injection molding, and isostatic pressing can be mentioned. The shaping conditions such as the pressure during shaping may be appropriately determined according to the type of raw material used, the use of the final product, etc. For example, conditions such as 0.01 to 400 MPa, preferably 0.05 to 100 MPa, more preferably 0.1 to 10 MPa, etc. can be mentioned. Also, the shape of the shaped body is not limited, and it may be any of a columnar body, a cylindrical body (pipe shape), a spherical body, a rectangular parallelepiped, a plate-like body, etc. Preferably, as the shape of the shaped body, a cylindrical shape with a diameter of about 10 to 30 mm and a height of about 10 to 30 mm is suitable. Also, the mixture obtained above may be binder granulated into a shaped body. The binder is not particularly limited, and any material suitable for assisting the granulation of the mixture can be used. The addition amount of the binder may be appropriately adjusted to an amount that enables granulation. Binder materials include organic materials and inorganic materials. Examples of organic materials include dextrin, carboxymethyl cellulose, hydroxyethyl cellulose, xanthan gum, acrylic resin, polystyrene, polyvinyl alcohol, and carboxyvinyl polymer. Examples of inorganic materials include bentonite, sepiolite, smectite, silica, and diatomaceous earth.

[0039] The firing of the mixture (or molded body) in air or an oxidizing atmosphere can be carried out, for example, at 80 to 300 °C, preferably 100 to 200 °C, more preferably 100 to 150 °C, for example, for 30 minutes to 48 hours, preferably 1 hour to 36 hours, more preferably 2 to 24 hours. More preferably, first, a solvent is mixed with crystalline compounds such as specific zeolites and sepiolite, the above silicon-containing compound (silane coupling agent) is added, and the mixture is immersed at room temperature (25 °C ± 10 °C) for about 1 to 3 hours. Then, it is heated at about 80 to 120 °C for 12 to 36 hours, more preferably at 100 °C ± 10 °C for about 24 hours ± 2 hours (the first heating step). Then, the temperature is raised by about 10 to 20 °C, and it is heated at about 120 to 180 °C for 30 minutes to 3 hours, more preferably at 140 °C ± 10 °C for about 1 hour ± 20 minutes (the second heating step). Then, it is washed with a solvent, filtered, and the residue is heated at about 80 to 100 °C for about 1 to 3 hours to remove the solvent, and the target selective oil separation and removal agent can be obtained. Here, as the solvent, for example, toluene, acetone, isopropanol, etc. can be used. The oxidizing atmosphere means, for example, an atmosphere mainly containing oxygen, ozone or nitrogen dioxide. The firing reaction and / or condensation reaction of the above mixture (or molded body) can be carried out according to known ceramic firing methods and / or synthesis methods. For example, first, the reaction can be started by heating the mixture (or molded body) with heat from a hot plate, muffle furnace, discharge, laser irradiation, carbon heater, etc. The reaction proceeds by heating, and finally the target porous body can be obtained.

[0040] As a more specific example of the condensation reaction mentioned here, when an alkylmethoxysilane is used as a silane coupling agent and zeolite is used as a crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms, and titanium atoms, the silane coupling agent chemically reacts with the hydroxyl groups partially present in the zeolite as follows, and methanol is by-produced, and a reaction in which the silane coupling agent and the zeolite are bonded (condensation reaction or silane coupling reaction) can be mentioned. When chlorosilane is used as the silane coupling agent, chlorine is by-produced instead of methanol (see Scheme 1).

[0041] TIFF0007713700000002.tif16492[Scheme 1]

[0042] Hereinafter, specific examples of the present invention will be described, but it is explicitly confirmed that the examples are not intended to limit the scope of the present invention.

Examples

[0043] (Reagents) Details of the reagents used in the following examples and comparative examples are as follows. (Synthetic zeolite) ·LTA-type zeolite (structure code: LTA, zeolite type: A-type) SiO2 / Al2O3 molar ratio: 2.0, pore diameter of zeolite (measured by gas adsorption method): 4.1 Å, average particle diameter of zeolite (by laser diffraction / scattering method): 2.6 μm, the following formula (I): M z+ [(SiO2) x (Al2O3) y z- (I) In the case shown by the formula (I), in the formula (I), M is Na, z is 1, and x / y is 2.0 ·FAU-type zeolite (structure code: FAU, zeolite type: Y-type) ​SiO2 / Al2O3 molar ratio: 3.8, pore diameter of zeolite (measured by gas adsorption method): 7.4 Å, average particle diameter of zeolite (by laser diffraction / scattering method): 1.6 μm, the following formula (I): M z+ [(SiO2) x (Al2O3) y z- (I) When shown by, in formula (I), M is Na, z is 1, and x / y is 3.8 (Natural sepiolite) Sepiolite Si / Mg molar ratio: 1.53, average wire diameter (measured by mercury intrusion method): 0.05 μm, the following formula (II): Mg8Si 12 O 30 (OH)4(OH2)4·8H2O (II)

[0044] (Silane coupling agent) Silane coupling agent having an alkyl chain with 2 carbon atoms: Ethyltrichlorosilane (C2H5Cl3Si), product code of Tokyo Chemical Industry Co., Ltd.: E0188 Silane coupling agent having an alkyl chain with 6 carbon atoms: Trichlorohexylsilane (C6H 13 Cl3Si), product code of Tokyo Chemical Industry Co., Ltd.: H0547 Silane coupling agent having an alkyl chain with 8 carbon atoms: n-Octyltrichlorosilane (C8H 17 Cl3Si), product code of Tokyo Chemical Industry Co., Ltd.: O0168 Silane coupling agent having an alkyl chain with 10 carbon atoms: Decyltrichlorosilane (C 10 H 25 Cl3Si), Dow Corning Toray Co., Ltd. Silane coupling agent having an alkyl chain with 12 carbon atoms: Dodecyltrichlorosilane (C 12 H 25 Cl3Si), product code of Tokyo Chemical Industry Co., Ltd.: D1509 Silane coupling agent having an alkyl chain with 18 carbon atoms: Trichlorooctadecylsilane (C 18 H 37 ​(Cl3Si) Manufactured by Tokyo Chemical Industry Co., Ltd. Product Code: O0079

[0045] (Lubricating oil) Daphne Super Hydro (Registered Trademark) 22A by Idemitsu Kosan Co., Ltd. (Coolant (Cutting oil diluent)) Water-soluble cutting oil, Product No.: 821 by Acezet Co., Ltd. was diluted to 5% by volume with water.

[0046] (Other solvents) Toluene: C7H8 Special Grade by Fujifilm Wako Pure Chemical Corporation Hexane: C6H 14 Special Grade by Fujifilm Wako Pure Chemical Corporation Acetone: C3H6O Special Grade by Fujifilm Wako Pure Chemical Corporation (Equipment used) Magnetic crucible: 50 mL by AS ONE Corporation Hot plate: Model: HP88854200 by Thermo Fisher Scientific Muffle furnace: Model: FP32 by Yamato Corporation Stirring rod by AS ONE Corporation Filter paper: Quantitative filter paper No. 5C by Advantec Toyo Kaisha, Ltd.

[0047] (Synthesis method of selective oil separation and removal agent) (Comparative Examples 1 - 3) In Comparative Example 1, only LTA-type zeolite was used. In Comparative Example 2, only FAU-type zeolite was used. In Comparative Example 3, only sepiolite was used. (Comparative Example 4) In Comparative Example 4, Oilrex (Registered Trademark) (by Funayama Corporation) was used. (Comparative Example 5) In Comparative Example 5, activated carbon (by Fujifilm Wako Pure Chemical Corporation) was used.

[0048] Comparative Example 6 (LTA-type zeolite - C2) In a magnetic crucible, 20 mL of toluene was mixed with 10 g of LTA-type zeolite, and the magnetic crucible was shaken so that the liquid would not spill, and the mixture was stirred until the lumps of the zeolite disappeared. 1 g of a silane coupling agent having an alkyl chain with 2 carbon atoms (ethyltrichlorosilane) was added thereto, and the mixture was stirred until the liquid became transparent and then immersed at room temperature (25 °C) for 1 hour. After the immersion, it was transferred to a hot plate and heated at 100 °C for 24 hours. Further, it was transferred to a muffle furnace at 140 °C and held for 1 hour. The obtained powder was put into 200 mL of acetone, mixed with a stirring rod, and then filtered using filter paper. The filtration residue was placed in a magnetic crucible, transferred to a muffle furnace at 80 °C, and held for 2 hours to volatilize acetone, obtaining Sample Powder 1. The mass of Sample Powder 1 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained Sample Powder 1 were the same as those of the above LTA-type zeolite used as the raw material.

[0049] Example 1 (LTA-type zeolite - C6) Sample Powder 2 was obtained through the same manufacturing process as Comparative Example 6, except that a silane coupling agent having an alkyl chain with 6 carbon atoms (trichlorohexylsilane) was used as the silane coupling agent. The mass of Sample Powder 2 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained Sample Powder 2 were the same as those of the above LTA-type zeolite used as the raw material.

[0050] Example 2 (LTA-type zeolite - C8) Sample Powder 3 was obtained through the same manufacturing process as Comparative Example 6, except that a silane coupling agent having an alkyl chain with 8 carbon atoms (n-octyltrichlorosilane) was used as the silane coupling agent. The mass of Sample Powder 3 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained Sample Powder 3 were the same as those of the above LTA-type zeolite used as the raw material.

[0051] Example 3 (LTA-type zeolite - C10) A sample powder 4 was obtained through the same manufacturing process as in Comparative Example 6, except that a silane coupling agent having an alkyl chain with 10 carbon atoms (decyltrichlorosilane) was used as the silane coupling agent. The mass of the sample powder 4 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained sample powder 4 were the same as those of the above LTA-type zeolite used as the raw material.

[0052] Example 4 (LTA-type zeolite - C12) A sample powder 5 was obtained through the same manufacturing process as in Comparative Example 6, except that a silane coupling agent having an alkyl chain with 12 carbon atoms (dodecyltrichlorosilane) was used as the silane coupling agent. The mass of the sample powder 5 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained sample powder 5 were the same as those of the above LTA-type zeolite used as the raw material.

[0053] Example 5 (LTA-type zeolite - C18) A sample powder 6 was obtained through the same manufacturing process as in Comparative Example 6, except that a silane coupling agent having an alkyl chain with 18 carbon atoms (trichlorooctadecylsilane) was used as the silane coupling agent. The mass of the sample powder 6 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained sample powder 6 were the same as those of the above LTA-type zeolite used as the raw material.

[0054] Example 6 (FAU-type zeolite - C8) A sample powder 7 was obtained through the same manufacturing process as in Comparative Example 6, except that a silane coupling agent having an alkyl chain with 8 carbon atoms (n-octyltrichlorosilane) was used as the silane coupling agent and FAU-type zeolite was used instead of LTA-type zeolite. The mass of the sample powder 7 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained sample powder 7 were the same as those of the above FAU-type zeolite used as the raw material.

[0055] Example 7 (FAU-type zeolite - C10) A sample powder 8 was obtained through the same production process as in Comparative Example 6, except that a silane coupling agent having an alkyl chain with 10 carbon atoms (decyltrichlorosilane) was used as the silane coupling agent, and FAU-type zeolite was used instead of LTA-type zeolite. The mass of the sample powder 8 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained sample powder 8 were the same as those of the above FAU-type zeolite used as the raw material.

[0056] Example 8 (FAU-type zeolite - C18) A sample powder 9 was obtained through the same production process as in Comparative Example 6, except that a silane coupling agent having an alkyl chain with 18 carbon atoms (trichlorooctadecylsilane) was used as the silane coupling agent, and FAU-type zeolite was used instead of LTA-type zeolite. The mass of the sample powder 9 was 8 g. Also, the values of the SiO2 / Al2O3 molar ratio, pore diameter, and average particle diameter of the obtained sample powder 9 were the same as those of the above FAU-type zeolite used as the raw material.

[0057] Example 9 (Sepiolite - C8) In a magnetic crucible, 20 mL of toluene was mixed with 10 g of sepiolite, and the magnetic crucible was shaken so that the liquid would not spill, and they were mixed until the lumps of the above sepiolite disappeared. 1 g of a silane coupling agent having an alkyl chain with 8 carbon atoms (n-octyltrichlorosilane) was added thereto, and it was immersed at room temperature (25 °C) for 1 hour. After immersion, it was transferred to a hot plate and heated at 100 °C for 24 hours. Further, it was transferred to a muffle furnace at 140 °C and held for 1 hour. The obtained powder was put into 200 mL of acetone, mixed with a stirring rod, and then filtered using filter paper. The filtration residue was placed in a magnetic crucible, transferred to a muffle furnace at 80 °C, and held for 2 hours to volatilize acetone, obtaining a sample powder 10. The mass of the sample powder 10 was 8 g. Also, the values of the SiO2 / MgO molar ratio and average wire diameter of the obtained sample powder 10 were the same as those of the above sepiolite used as the raw material.

[0058] Example 10 (Sepiolite - C10) Sample powder 11 was obtained through the same manufacturing process as in Example 9, except that a silane coupling agent having an alkyl chain with 10 carbon atoms (decyltrichlorosilane) was used as the silane coupling agent. The mass of the sample powder 11 was 8 g. Also, the SiO2 / MgO molar ratio and the average wire diameter value of the obtained sample powder 11 were the same as those of the above-mentioned sepiolite used as the raw material.

[0059] Example 11 (Sepiolite-C18) Sample powder 12 was obtained through the same manufacturing process as in Example 9, except that a silane coupling agent having an alkyl chain with 18 carbon atoms (trichlorooctadecylsilane) was used as the silane coupling agent. The mass of the sample powder 12 was 8 g. Also, the SiO2 / MgO molar ratio and the average wire diameter value of the obtained sample powder 12 were the same as those of the above-mentioned sepiolite used as the raw material.

[0060] [Test Example] (Change in properties) 10 mL of the coolant liquid was measured into a beaker, 3.0 g of the sample powder obtained in the comparative example and the example was added, and the mixture was stirred with a stir bar for 3 minutes. After mixing, the mixture was allowed to stand for 1 hour, and the properties of the coolant liquid before and after adding the sample powder were visually recorded. The state of the coolant liquid was evaluated based on the following criteria. Note that the change in appearance refers to the fact that the color of the coolant liquid changed from opaque to transparent. (Change in properties due to adsorption of components in the coolant liquid) The change in the properties of the coolant liquid was evaluated based on the following evaluation criteria. 〇 (Acceptable): No change in the properties of the coolant liquid × (Unacceptable): The viscosity of the coolant liquid decreased and the appearance (color) changed.

[0061] (Oil adsorption) 3 g of the sample powder obtained in the comparative example and the example was weighed into a petri dish, and 0.5 g of lubricating oil was dropped into it one by one, and mixed with a medicine spoon. When the sample powder and the lubricating oil were mixed, at first, it formed lumps and agglomerates, but as the dropping amount of the lubricating oil increased, liquid lubricating oil also appeared. The end point was defined as the time when the sample powder was sufficiently dispersed in the lubricating oil and there were no more lumps (agglomerates), and the dropping amount of the lubricating oil at that time was recorded as an index of the adsorption amount of the lubricating oil adsorbed by the sample powder. The dropping amount of the lubricating oil (oil adsorption amount) was evaluated based on the following criteria. <Lubricating oil dropping amount (oil adsorption amount)> Based on the following evaluation criteria, the lubricating oil dropping amount was evaluated. ◎ (Excellent): More than 2.5 g to 3.0 g 〇 (Good): More than 2.0 g to 2.5 g or less △ (Fair): More than 0.5 g to 2.0 g or less × (Poor): More than 0.1 g to 0.5 g or less

[0062] (Selective oil adsorption) 1 mL of lubricating oil was added to 10 mL of coolant liquid and mixed to prepare a mixed liquid. 3.0 g of the sample powder was added thereto and mixed with a stirrer for 3 minutes. After mixing, it was allowed to stand for 1 hour, and the properties of the coolant liquid and the lubricating oil before and after adding the sample powder were visually recorded. Furthermore, as the adsorption rate of the lubricating oil, the volume % of the lubricating oil adsorbed by 3 g of the sample powder with respect to the volume of the added lubricating oil was calculated and used as the adsorption rate. Specifically, the difference between the volume of the aggregate of the sample powder separated and recovered from the coolant liquid by filtration and the volume of the initially added 3 g of the sample powder was regarded as the volume of the adsorbed lubricating oil. Then, the ratio of the volume of the adsorbed lubricating oil to the volume of the initially added 1 mL of lubricating oil was calculated as a percentage and used as the adsorption rate. The properties of the coolant liquid and the adsorption rate of the lubricating oil were evaluated based on the following criteria. <Selective oil adsorption> Based on the following evaluation criteria, the selective oil adsorption was evaluated. ◎ (Excellent): There is no change in the properties of the coolant liquid, and the adsorption rate is more than 90% to 100% 〇 (Good): There is no change in the properties of the coolant liquid, and the adsorption rate is more than 70% to 90% or less □(Good): There is no change in the properties of the coolant liquid, and the adsorption rate is over 30% to 70% or less. △(Fair): There is no change in the properties of the coolant liquid, and the adsorption rate is 0% to 30% or less. ×(Poor): The viscosity of the coolant liquid decreases and the appearance changes, and the adsorption rate is 0% to 30% or less.

[0063] The property changes of the above-mentioned coolant liquid, the oil adsorption by the sample powder, and the selective oil adsorption in each comparative example and example are summarized in Tables 1 and 2 below.

[0064] Table 1 TIFF0007713700000003.tif57162

[0065] Table 2 TIFF0007713700000004.tif93164

[0066] Compared with Comparative Examples 1 to 6, the effects of Examples 1 to 11 as selective oil adsorbents were recognized. In particular, regarding the number of carbon atoms of the alkyl substituent, it was shown that FAU-type zeolite - C10 to FAU-type zeolite - C18 and sepiolite - C10 to sepiolite - C18 have high effects as selective oil separation and removal agents.

[0067] Also, as is clear from the high oil adsorption capacity shown by Examples 1 to 11, it can be easily understood that the composite materials in Examples 1 to 11 can widely adsorb oil and can also adsorb contaminants mixed in the liquid accompanying the adsorption of oil.

Claims

1. A selective oil separation and removal agent containing a composite material obtained by immobilizing an alkyl substituent having 6 to 18 carbon atoms on a porous inorganic material other than ZSM-5 zeolite and ZSM-8 zeolite.

2. The selective oil separation and removal agent according to claim 1, wherein the alkyl substituent is bonded to the porous inorganic material via a silicon atom.

3. The selective oil separation and removal agent according to claim 1 or 2, wherein the porous inorganic material is a crystalline compound containing one or more oxides of atoms selected from the group consisting of silicon atoms, aluminum atoms, calcium atoms, magnesium atoms, and titanium atoms.

4. The selective oil separation and removal agent according to claim 3, wherein the crystalline compound is selected from the group consisting of zeolite, bentonite, acid clay, activated clay, attapulgite, sepiolite, cristobalite, sericite, pumice, vermiculite, perlite, and diatomaceous earth.

5. The selective oil separation and removal agent according to claim 3, wherein the crystalline compound is zeolite, and the atomic ratio of Si / Al in the zeolite is 0.1 to 100.

6. The selective oil separation and removal agent according to claim 3, wherein the crystalline compound is a zeolite having a structure code selected from the group consisting of FAU, LTA, FER, MWW, MOR, LTL, and BEA.

7. The selective oil separation and removal agent according to claim 3, wherein the crystalline compound is sepiolite, and the atomic ratio of Si / Mg in the sepiolite is 0.1 to 100.

8. The selective oil separation and removal agent according to any one of claims 1 to 7, wherein the alkyl substituent has 8 to 18 carbon atoms.

9. The selective oil separation and removal according to any one of claims 1 to 8, wherein the selective oil separation and removal by the agent is separation and removal of the oil by selective adsorption of the oil present on the surface of the cutting oil diluent and / or mixed in the cutting oil diluent from the cutting oil diluent.

10. The selective oil separation and removal agent according to claim 9, wherein the cutting oil diluent is a water-soluble coolant liquid.

11. The selective oil separation and removal agent according to claim 10, wherein the coolant liquid is an emulsion.

12. The selective oil separation and removal agent according to any one of claims 9 to 11, wherein the Snyder's polarity parameter of the oil is 10.0 or less.

13. The selective oil separation and removal agent according to any one of claims 9 to 12, wherein the polarity of the oil component is smaller than the polarity of the cutting oil agent dilution liquid.

14. A method for selectively separating and removing an oil component present on the surface of a cutting oil agent dilution liquid and / or mixed in the cutting oil agent dilution liquid, a step of mixing the selective oil separation and removal agent according to any one of claims 1 to 13 with the cutting oil agent dilution liquid in which the oil component is present on the surface and / or mixed; a step of stirring the cutting oil agent dilution liquid to adsorb the oil component to the selective oil separation and removal agent; and a step of separating and removing the selective oil separation and removal agent adsorbed with the oil component from the cutting oil agent dilution liquid A method for selectively separating and removing an oil component present on the surface of a cutting oil agent dilution liquid and / or mixed in the cutting oil agent dilution liquid, comprising the above steps.

15. (1) A step of preparing a porous inorganic substance which is a crystalline compound containing one or more oxides of atoms selected from the group consisting of a silicon atom, an aluminum atom, a calcium atom, a magnesium atom, and a titanium atom; (2) A step of preparing a silane coupling agent having an alkyl substituent having 6 to 18 carbon atoms; (3) A step of mixing the porous inorganic substance and the silane coupling agent; and (4) A step of firing the mixture in air or an oxidizing atmosphere, A method for producing the selective oil separation and removal agent according to any one of claims 2 to 13, comprising the above steps.

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