Method for removing organic lead compound and method for producing organosilicon compound

Abstract

To provide a novel method for removing an organic lead compound that enables removal of the organic lead compound, and a method for producing an organosilicon compound using the method.SOLUTION: Provided is a method for removing an organic lead compound from a liquid containing an organic lead compound, the method including a treatment step of incorporating hydrogen halide into the liquid and reacting the organic lead compound with the hydrogen halide.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a method for removing an organolead compound and a method for producing an organosilicon compound.

Background Art

[0002] Heavy metals are known to affect the human body and cause health problems when excessively taken into the body. In particular, lead, which is a kind of heavy metal, is likely to accumulate in the body and difficult to excrete, so it is likely to cause poisoning symptoms. Lead can be contained in various products. For example, it may also be contained as an impurity in raw materials used in organic synthesis. When lead is contained in such raw materials, lead reacts with organic compounds during the process of organic synthesis to form organolead compounds. Since organolead compounds are easily dissolved in organic solvents and hardly dissolved in aqueous solvents, it is difficult to remove them by separation and other treatments in the synthesis of organic compounds, etc. Also, since the molecular size tends to be larger compared to lead itself (including lead ions) and inorganic lead compounds, there has been a problem that it is difficult to remove them by filtration, adsorption, or other treatments. As a method for removing an organolead compound, for example, Patent Document 1 discloses a method for removing an organolead compound by irradiating a liquid containing the organolead compound with ultraviolet light.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Regarding the method for removing an organolead compound in a liquid, although studies have been conducted focusing on treatments from the outside of the liquid such as ultraviolet irradiation, studies focusing on the components in the liquid have not been sufficiently conducted, and there has been room for further study. Therefore, an object of the present invention is to provide a new method for removing an organolead compound and a method for producing an organosilicon compound using the method, which can remove the organolead compound.

Means for Solving the Problems

[0005] As a result of intensive studies, the present inventors have found that the above problems can be solved by adding a specific substance to a solution containing an organolead compound, and have completed the present invention.

[0006] That is, the gist of the present invention is as follows. Item 1 An organolead removal method for removing an organolead compound from a liquid containing an organolead compound, The method for removing an organolead compound includes a treatment step of containing hydrogen halide in the liquid and reacting the organolead compound with the hydrogen halide. Item 2 The method for removing an organolead compound according to Item 1, wherein in the treatment step, hydrogen halide is contained in the liquid by one or more treatments selected from a treatment of generating hydrogen halide by reacting a halogen-containing compound in the liquid and a treatment of mixing the liquid and hydrogen halide. Item 3 The method for removing an organolead compound according to Item 1 or 2, wherein the total molar amount of hydrogen halide with respect to the volume of the liquid after containing the hydrogen halide is 0.01 mol / L or more and 5.0 mol / L or less. Item 4 The method for removing an organolead compound according to any one of Items 1 to 3, including a purification step of removing a lead component contained in the liquid in at least one of during and after the treatment step. Item 5 The method for removing an organolead compound according to any one of Items 1 to 4, including an irradiation step of irradiating the liquid with ultraviolet rays after the treatment step. Item 6 The method for removing an organolead compound according to any one of Items 1 to 5, wherein the treatment step includes a reaction treatment of performing a Grignard reaction. Item 7 The method for removing an organolead compound according to Item 6, including a synthesis treatment of synthesizing an alkoxylated organosilicon compound through at least the reaction treatment. ​ Item 8. The method for removing an organolead compound according to Item 6 or 7, including a liquid separation treatment in which, after the reaction treatment, an aqueous solution containing an acid and the organosilicon compound-containing liquid are mixed to separate the organosilicon compound-containing liquid into an organic phase and an aqueous phase. Item 9. A method for producing an organosilicon compound, including a step of removing an organolead compound by the method for removing an organolead compound according to any one of Items 1 to 8.

Advantages of the Invention

[0007] According to the present invention, it is possible to provide a new method for removing an organolead compound capable of removing an organolead compound, and a method for producing an organosilicon compound using the method.

Embodiments for Carrying Out the Invention

[0008] Embodiments of the present invention will be described in detail below, but the present invention is not limited to these contents as long as the gist thereof is not exceeded. Further, the present invention can be arbitrarily modified and implemented within the scope not departing from the gist thereof. In this specification, a numerical range represented by "~" means a range including the numerical values described before and after "~" as a lower limit value and an upper limit value, and "A~B" means A or more and B or less. Further, when the numerical range is described stepwise, the upper limit and the lower limit of each numerical range can be arbitrarily combined. In this specification, the expression "A or B" may be read as "at least one selected from the group consisting of A and B". In this specification, the expression "the amount of B with respect to the amount of A" represents "the amount of B / the amount of A". In this specification, a plurality of embodiments are described, and various conditions in each embodiment can be applied to each other within the applicable range.

[0009] <Method for Removing Organolead Compound> The method for removing an organolead compound according to an embodiment of the present invention (hereinafter, also simply referred to as "the method for removing an organolead compound") is a method for removing an organolead compound from a liquid containing the organolead compound, which includes a treatment step of containing hydrogen halide in the liquid and reacting the organolead compound with the hydrogen halide. The above method for removing an organolead compound may include steps other than the above treatment step. In addition, the removal of the organolead compound in the present invention means that the content ratio of the organolead compound in the liquid containing the organolead compound decreases, and not only the content ratio of the organolead compound decreases because the organolead compound is discharged out of the liquid, but also the content ratio of the organolead compound decreases because the bond between lead and carbon in the organolead compound is cleaved. In the present specification, lead and compounds containing lead are collectively referred to as "lead components". The lead components include compounds containing lead after the bond between lead and carbon in the organolead compound is cleaved.

[0010] As described above, since organolead compounds are easily soluble in organic solvents and hardly soluble in aqueous solvents, it is difficult to remove them by treatments such as liquid separation in the synthesis of organic compounds, etc. Also, since the molecular size tends to be larger compared to lead itself (including lead ions) and inorganic lead compounds, there has been a problem that it is difficult to remove them by treatments such as filtration and adsorption. As a result of intensive studies, the present inventors have found that when an organolead compound reacts with hydrogen halide, the bond between lead and carbon in the organolead compound is cleaved. And the present inventors have invented the method according to the above embodiment as a method for removing an organolead compound. The lead component generated by decomposition from the organolead compound by this method can be easily removed by purification treatment or the like.

[0011] [Treatment Step] The method for removing an organolead compound according to the present embodiment is a method for removing an organolead compound from a liquid containing the organolead compound, which includes a treatment step of containing hydrogen halide in the liquid and reacting the organolead compound with the hydrogen halide. The method for removing an organolead compound from a liquid containing the organolead compound is not particularly limited as long as a treatment is carried out in which hydrogen halide is contained in the liquid and the organolead compound is reacted with the hydrogen halide. As described above, when hydrogen halide is contained in a liquid, the organolead compound reacts with the hydrogen halide, and the bond between the lead atom and the carbon atom in the organolead compound is cleaved, so that the content ratio of the organolead compound in the liquid decreases. When a component that neutralizes hydrogen halide is contained in the liquid when hydrogen halide is added, the reaction between the hydrogen halide and the organolead compound will not occur. Therefore, it is preferable that the liquid does not contain a component that neutralizes hydrogen halide at the time when hydrogen halide is added. Examples of the component that neutralizes hydrogen halide include basic compounds, and specifically, amino group-containing compounds and the like can be mentioned.

[0012] The organolead compound is not particularly limited as long as it is a compound in which a lead atom is bonded to a carbon atom of an organic compound. The specific form of the organic compound is determined according to the materials used and the like. There is no particular limitation on how the organolead compound is contained in the liquid. For example, the organolead compound may be contained as an impurity in the raw material of the component constituting the liquid, and the organolead compound may be directly contained in the liquid when the raw material is blended. Alternatively, a reaction may be carried out in the process of obtaining the liquid, and the organolead compound may be generated by the reaction.

[0013] In the process of obtaining a liquid, a reaction is carried out, and as an embodiment in which an organolead compound is produced by the reaction, for example, in the process of carrying out a Grignard reaction, when a lead component is contained in the raw materials used, a mode in which the lead component reacts with the Grignard reagent to produce an organolead compound can be mentioned. More specifically, for example, when lead chloride reacts with methylmagnesium chloride as a Grignard reagent, tetramethyllead is produced. Although magnesium is used in the Grignard reaction, commercially available magnesium (commercial products) usually contains lead components such as lead(II) chloride or lead(IV) chloride as impurities. In this specification, "magnesium" means a magnesium element unless otherwise specified, and the magnesium element can exist, for example, in the form of metallic magnesium or in the form of a magnesium salt.

[0014] The content of the lead component in the liquid before the treatment of containing hydrogen halide in the liquid is not particularly limited, and usually, it is larger than the upper limit of the range of the content of lead atoms in the finally obtained liquid described later.

[0015] The method for evaluating the composition and content of the lead component in the liquid is not particularly limited, and for example, it can be evaluated by ICP-mass (ICP-MS) or the like.

[0016] In order to sufficiently advance the reaction between the organolead compound and hydrogen halide, the treatment process preferably includes a treatment of holding the liquid containing hydrogen halide after adding hydrogen halide to the liquid. The holding time is not particularly limited, and for example, it may be 1 second or more, 5 seconds or more, 10 seconds or more, 1 minute or more, 1 hour or more, and also may be 10 hours or less, 5 hours or less. When this holding treatment is applied, the above-mentioned "treatment of reacting the organolead compound with hydrogen halide" is substantially the same treatment as the "treatment of holding the liquid containing hydrogen halide", so the "treatment of reacting the organolead compound with hydrogen halide" is the "holding of the liquid containing hydrogen halide" It may be rephrased as "the process to be carried out". The process to be retained only needs to be able to retain hydrogen halide in the liquid, and it may be carried out in parallel with other processes.

[0017] (Hydrogen Halide Containing Process) The method for carrying out the process of containing hydrogen halide in the liquid (hydrogen halide containing process) is not particularly limited. For example, it can be carried out by one or more processes selected from the process of generating hydrogen halide by reacting a halogen-containing compound such as an organic halide in the liquid, and the process of mixing the liquid and hydrogen halide. When hydrogen halide is contained in a liquid containing an organolead compound, the organolead compound and hydrogen halide will react unless it is in an environment where a component that neutralizes hydrogen halide coexists.

[0018] The type of hydrogen halide is not particularly limited and may be any of hydrogen fluoride, hydrogen chloride, hydrogen bromide, or hydrogen iodide. However, from the perspective of handling and side reactions, hydrogen chloride is preferred. Note that hydrogen halide may exist as a hydrohalic acid in the liquid.

[0019] The concentration of hydrogen halide to be contained in the liquid is not particularly limited. However, from the perspective of enhancing the efficiency of cleavage of the lead-carbon bond, it is preferably 0.01 mol / L or more, more preferably 0.05 mol / L or more, and particularly preferably 0.1 mol / L or more, as the total amount (mol) of hydrogen halide with respect to the amount (volume) of the liquid after containing hydrogen halide. Also, from the perspective of suppressing side reactions caused by hydrogen halide, it is preferably 5.0 mol / L or less, and particularly preferably 2.0 mol / L or less.

[0020] The evaluation method for the number of moles of the above organolead compound is not particularly limited, and it can be carried out using ICP-MS (for example, ICP-MS7900 manufactured by Agilent Technologies).

[0021] Regarding the total number of moles of hydrogen halide to be contained in the above liquid, in the process of mixing the liquid and hydrogen halide, it can be directly obtained from the amount of hydrogen halide to be mixed, and in the process of generating hydrogen halide by reacting a halogen-containing compound in the liquid, it can also be predicted from the charged amounts of each raw material.

[0022] The method of generating hydrogen halide by reacting a halogen-containing compound in the liquid is not particularly limited, and it can be carried out by a known method or a combination of known methods. The halogen-containing compound is a halogen-containing compound that decomposes by itself to generate hydrogen halide, or a halogen-containing compound that decomposes by reacting with another compound to generate hydrogen halide. For example, there is a method of reacting a halogen-containing compound with a hydrogen-containing compound capable of extracting a halogen atom from the compound and reacting with hydrogen to generate hydrogen halide. Specifically, for example, by adding an alcohol such as methanol to a liquid containing a halogen-containing compound such as a halogenated silane, the halogen-containing compound and the alcohol react to generate hydrogen halide.

[0023] The type of the halogen-containing compound in the process of generating hydrogen halide by reacting a halogen-containing compound in the liquid is not particularly limited, and any compound containing a halogen may be used. For example, alkyl halides, aryl halides, cyclic alkyl halides, or halogenated silanes, etc. may be mentioned. Also, the halogen-containing compound may be halogen itself. The form of the halogen-containing compound is not particularly limited, and it may be either a gas or a liquid.

[0024] The method of mixing the liquid and hydrogen halide is not particularly limited. For example, a method of contacting and mixing the liquid with liquid hydrogen halide (which may be a liquid containing hydrogen halide), or a method of contacting and mixing gaseous hydrogen halide with the liquid, etc. may be mentioned.

[0025] (Other processes) The treatment process may include treatments other than the above hydrogen halide-containing treatment (other treatments). For example, it may include reaction treatments other than the reaction for generating the above hydrogen halide, specifically, the reaction treatments shown in the method for producing an organosilicon compound described later, particularly the reaction treatment for synthesizing an alkoxylated organosilicon compound. Furthermore, it may include polycondensation treatments and the like shown in the method for producing an organosilicon compound described later.

[0026] [Purification process] The method for removing an organolead compound may include a purification process (which may also be referred to as a "purification treatment") for removing a lead component (simply referred to as the "lead component") generated by cleavage of the bond between a lead atom and a carbon atom in the organolead compound in the above treatment process and / or at least one of after the treatment process. The form of the lead component is not particularly limited, but it usually exists as a salt formed by a lead ion and an anion contained in a liquid. The method for removing the lead component is not particularly limited as long as it can remove the lead component, and known methods can be used. Specifically, liquid separation treatment, filtration treatment, adsorption treatment, etc. described below can be mentioned. From the viewpoints of reducing the manufacturing cost because the treatment can be carried out in a batch system, reducing the raw material cost because no raw materials are required other than water and inexpensive salts, and completing the treatment in a relatively short time, it is preferable to adopt liquid separation treatment. Treatments other than liquid separation treatment that can be carried out in a batch system include precipitation removal of salts by concentration treatment or solvent replacement treatment, etc., and known techniques can be applied to these treatments. When purification is carried out by filtration or activated carbon treatment, it is necessary to transfer the liquid contained in a predetermined container to another container such as a container having a filtration membrane or a container containing activated carbon, and it is difficult to carry out the treatment in a batch system. On the other hand, when liquid separation treatment is adopted, purification of the liquid can be carried out in a predetermined container without transferring the liquid between containers, so the treatment in a batch system is easy, the manufacturing cost can be reduced, and ultimately the product price of the product manufactured through this treatment can be reduced. In addition, the processes other than the liquid separation process are not limited, and the processes other than the liquid separation process may be appropriately used. For example, each process such as the liquid separation process, the concentration process, or the solvent replacement process can be carried out in a batch system, and after passing through the irradiation process described later, the adsorption process or the like can be finally carried out.

[0027] The purification step may use one type of process, or may combine and use a plurality of types of processes. Also, the number of times of the purification step is not particularly limited, and it may be once or may be carried out a plurality of times. In addition, the processes for purification as described in this section can be used not only for removing lead components but also for removing other components.

[0028] [Liquid separation process] By performing liquid separation, the lead component in the liquid can be removed. The method of liquid separation is not particularly limited. For example, when the liquid contains an organic compound and an organic solvent, the lead component can be removed by bringing the liquid into contact with water or an acid and then removing the aqueous phase. When using water, an acid such as nitric acid or hydrochloric acid may be further used to increase the solubility of the lead component in water. When these acids are used as dilute acids, the concentration of the acid may be, for example, 0.001 to 1 mol / L or the like. The method for removing water in the organic phase is not particularly limited, and it can be removed, for example, by a dehydrating agent such as magnesium sulfate, sodium sulfate, or molecular sieves.

[0029] The temperature at which the liquid is brought into contact with water is not particularly limited and may be appropriately set at a temperature at which the organic compound and the organic solvent are stable, such as 0 to 30°C.

[0030] By performing the above-described method for removing lead components, it is possible to significantly reduce the lead content in a liquid containing lead components, and it is also possible to efficiently reduce the lead content to the level of several tens of ppb on a mass basis. Therefore, by using this removal method, the purity of the component to be collected can be improved, and it can be suitably used in applications such as electronic materials and pharmaceutical raw materials. Depending on the type of the component to be collected, it is also possible to improve the purity by performing known purification operations such as recrystallization or column chromatography.

[0031] As an example of the case where the liquid contains an organosilicon compound, after the reaction treatment described below, by mixing the liquid containing the organosilicon compound, particularly the liquid containing the organosilicon compound, the organic solvent and magnesium, with an aqueous solution containing an acid, a liquid separation treatment for separating the liquid containing the organosilicon compound into an organic phase and an aqueous phase can be employed. Examples of the acid include oxalic acid, carbonic acid, tartaric acid, and the like. By the above-described treatment, not only can the organolead compound in the liquid containing the organosilicon compound be removed, but as described below, it is also possible to easily suppress the liquid from becoming a one-phase gel-like liquid with high viscosity. The present inventors have found that when the organosilicon compound contained in the liquid is an organosilicon compound having a coordinating functional group and the liquid further contains magnesium, the coordinating functional group coordinates to magnesium and / or a magnesium salt, and the liquid becomes a one-phase gel-like liquid with high viscosity. Therefore, as a result of intensive studies by the present inventors, it has been found that by mixing a liquid containing an organosilicon compound or the like with an aqueous solution containing an acid capable of forming a salt insoluble with magnesium, the liquid can be separated into an organic phase and an aqueous phase.

[0032] (Filtration) When the lead component precipitates as an inorganic salt in the liquid, the lead component can be removed from the system by a filtration operation. However, it is difficult to reduce the lead component to the ppb level only by filtration. By performing a filtration operation using a filter or filter paper and collecting the filtrate, a liquid with reduced lead component can be obtained.

[0033] (Adsorbent treatment) When the liquid contains a component intended to be collected, it is also possible to adsorb and remove the lead component in the liquid by bringing the liquid containing the component and the lead component into contact with an adsorbent. As the adsorbent for removing the lead component, an ion exchange resin, a chelate resin, activated carbon, a synthetic adsorbent, etc. used in known metal treatments can be used.

[0034] Activated carbon may be used in any form of granular, powdered, or fibrous, and the raw material may be derived from natural products such as coconut shells or from synthetic resins. It is preferable to perform heat vacuum drying at 150 to 250 °C as a pretreatment. In the treatment using activated carbon, both batch treatment and column treatment can be applied. In batch treatment, specifically, 1 to 15% by mass of activated carbon is added to the liquid, and after stirring and shaking for 0.5 to 48 hours at a liquid temperature of 0 to 30 °C, the activated carbon is removed by filtration to obtain a liquid with reduced lead component. In column treatment, specifically, after filling activated carbon with an organic solvent in which an organic compound is dissolved in a cylindrical container such as PTFE, PFA, or glass, the liquid is passed through at a liquid temperature of 0 to 30 °C to obtain a liquid with reduced lead component.

[0035] As the ion exchange resin, a cation exchange resin can be used, and any cation exchange resin of strong acid type, weak acid type, gel type, or porous type may be used. As the chelate resin, a chelate resin used in known metal treatments can be used. Specific examples include iminodiacetic Examples include the acid type, nitrilotriacetic acid type, ethylenediaminetetraacetic acid type, diethylenetriaminepentaacetic acid type, or triethylenetetraminehexaacetic acid type. As the synthetic adsorbent, a polystyrene type or polymethacrylic acid type may be used. Specific examples include styrene-divinylbenzene copolymer, ethylstyrene-divinylbenzene copolymer, or methyl methacrylate-ethylene glycol dimethacrylate copolymer, etc. Those in which the benzene ring of styrene is substituted with a halogen such as bromine may also be used. As a pretreatment for the ion exchange resin, chelating resin, or synthetic adsorbent, it is preferable to perform an arbitrary treatment by a known method and then replace the solvent in the resin with a solvent that may be contained in the liquid. In the treatment of a liquid containing a lead component with an ion exchange resin, chelating resin, or synthetic adsorbent, etc., both batch treatment and column treatment can be applied. Specifically, a liquid with the lead component reduced can be obtained by the same operation as the above-mentioned activated carbon treatment.

[0036] [Irradiation step] The method for removing the organolead compound may include an irradiation step of irradiating the liquid with ultraviolet rays after the above-mentioned treatment step. Since the irradiation with the ultraviolet rays can further break the bond between the lead atom and the carbon atom in the organolead compound, the amount of the organolead compound in the liquid can be further reduced by combining with the above-mentioned treatment step. The irradiation step may be performed at a stage where the organolead compound may be contained in the liquid. Specifically, it may be performed at any stage before, during, or after the above-mentioned treatment step. Also, when performing the above-mentioned purification step, from the viewpoint of reducing the amount of the organolead compound in the final liquid, it is preferable to perform the irradiation step before the purification step. The method for irradiating ultraviolet rays is not particularly limited and can be performed by a known method.

[0037] The wavelength of the ultraviolet light is not particularly limited. From the perspective of efficiently removing the organolead compound, wavelengths of 210 to 350 nm are preferred, wavelengths of 220 to 320 nm are more preferred, and wavelengths of 240 to 300 nm are even more preferred. At wavelengths exceeding 350 nm, since there is no absorption derived from the organolead compound, the reaction hardly occurs, and the removal effect of the organolead compound tends to decrease. When the liquid contains an organic compound that is not desired to be removed, at short wavelengths less than 210 nm, side reactions due to the absorption of the organic compound tend to occur easily.

[0038] The ultraviolet irradiation dose is defined as the integrated light quantity, and the integrated light quantity is not particularly limited, but it may be appropriately adjusted according to the content of the organolead compound in the liquid. For example, it is preferably 0.1 to 100 J / cm 2 and more preferably 1 to 80 J / cm 2 and even more preferably 10 to 60 J / cm 2

[0039] The integrated light quantity can be obtained by multiplying the intensity of the ultraviolet light by the irradiation time. Therefore, it is preferable to appropriately set the intensity of the ultraviolet light to be irradiated and the irradiation time so that the integrated light quantity falls within the above range.

[0040] The device for irradiating ultraviolet light is not particularly limited as long as it uses a light source that emits ultraviolet light, and an ultraviolet fluorescent lamp, a mercury lamp, a deuterium lamp, an ultraviolet LED, an ultraviolet laser, or the like can be used.

[0041] The method of irradiating ultraviolet light is not particularly limited, and it is sufficient to irradiate the liquid with ultraviolet light. From the perspective of efficiency improvement, as a container for containing the liquid, a quartz container or the like with high ultraviolet transmittance is preferably used, and a method of irradiating the container with ultraviolet light is preferred.

[0042] When the irradiation step is adopted, the liquid may contain the following components in terms of enhancing the effect of ultraviolet irradiation. Examples of the components that can enhance the effect of ultraviolet irradiation include benzophenone, ​Examples of photosensitizers include anthracene, camphorquinone, etc. When the organolead compound has a polymerizable group such as a (meth)acrylic group, vinyl group, or epoxy group, a polymerization inhibitor such as dibutylhydroxytoluene or benzoquinone may be added. The content of these components in the liquid is not particularly limited and may be appropriately determined in consideration of the desired effect. For example, if it is a photosensitizer, it may be 1 to 50% by mass, and if it is a polymerization inhibitor, it may be 1 to 50% by mass, for example.

[0043] The concentration of lead atoms in the finally obtained liquid is not particularly limited, and the lower the better. It is preferably 1000 mass ppb or less, more preferably 500 mass ppb or less, still more preferably 100 mass ppb or less, still more preferably 50 mass ppb or less, still more preferably 10 mass ppb or less, and still more preferably 5 mass ppb or less. The lower limit of the concentration does not particularly require setting and may be 0 mass ppb (below the detection limit), may be 0 mass ppb or more, or may be more than 0 mass ppb. The method for reducing the concentration of lead atoms in the finally obtained liquid is not particularly limited, and for example, the method described in the above purification step can be adopted. The finally obtained liquid is the liquid obtained in the final step of the method for removing organolead compounds according to the present embodiment. For example, if it is only the treatment step, it is the liquid obtained by the treatment step. If it includes a purification step and this step is the final step, it is the liquid obtained by this step. If it includes an irradiation step and this step is the final step, it is the liquid obtained by this step. Also, when including liquid separation treatment, it is the liquid contained in the phase containing the component to be taken (for example, when the target component is an organosilicon compound, the organic phase). The method for evaluating the concentration of the above lead atoms is not particularly limited, but it can be carried out using ICP-MS (for example, ICP-MS7900 manufactured by Agilent Technologies).

[0044] <Method for producing organosilicon compound> Another embodiment of the present invention is a method for producing an organosilicon compound, which includes a step of removing an organolead compound by the above-described method for removing an organolead compound. The production method is not particularly limited as long as it includes this step, and may include other steps. The type of the organosilicon compound is not particularly limited. Since an organolead compound may be contained in the raw material used for synthesizing the organosilicon compound or in the solution containing the raw material, by using the above-described method for removing an organolead compound, the amount of the organolead compound in the liquid used for producing the organosilicon compound can be reduced, and ultimately, an organosilicon compound with high purity can be obtained as the final product. Depending on the embodiment of the above-described method for removing an organolead compound, since an organosilicon compound can also be obtained by this method, the method for removing an organolead compound itself may be treated as a method for producing an organosilicon compound.

[0045] [Reaction treatment] Hereinafter, an example in the case of including a reaction treatment for synthesizing an alkoxylated organosilicon compound is shown, but it is not limited thereto. The reaction treatment can also be applied as the reaction treatment included in the treatment step in the above-described method for removing an organolead compound. As in this example, when the reaction treatment including a Grignard reaction is included in the treatment step, since an organolead compound is likely to be generated by the reaction between the lead component and the Grignard reagent as described above, the above-described method for removing an organolead compound can be preferably applied. Note that the reaction treatment may be performed in parallel with the above-described hydrogen halide-containing treatment or separately.

[0046] After reacting an organohalide, a halogenated organosilane compound, and magnesium to obtain an organosilicon compound, when the organosilicon compound and an alcohol are reacted, an alkoxylated organosilicon compound is generated and hydrogen halide is generated. Hereinafter, this reaction will be specifically described.

[0047] Organohalides such as alkyl halides, aryl halides, or alkenyl halides (R1 X a ;R 1 is an organic group, X is independently a halogen atom, a is an integer of 1 or more), a halogenated organic silane compound (SiR 2 b Y 4-b ; Y is independently a halogen atom, R 2 is independently a hydrogen atom or an organic group, b is an integer from 0 to 3), and magnesium are prepared and mixed. First, the organic halide reacts with magnesium to form a Grignard reagent (R 1 (X) a-1 MgX), and then the Grignard reagent reacts with the halogenated organic silane compound, and at least a part of Y of the halogenated organic silane compound is replaced by R 1 to form an organosilicon compound.

[0048] The above reaction will be described more specifically with an example. For example, when R 1 X2 is used as the organic halide and SiR 2 Y3 is used as the halogenated organic silane compound, first, a Grignard reagent (R 1 (X)MgX) is formed by the reaction of the organic halide with magnesium (Mg), and then the Grignard reagent reacts with the halogenated organic silane compound, and at least a part of Y of the halogenated organic silane compound is replaced by R 1 to form an organosilicon compound having the structure shown in the following formula (1) (hereinafter also referred to as compound (1)). Furthermore, a Grignard reagent (XMgR 1 Si(R 2 )(Y)2) is formed by the reaction of compound (1) with magnesium (Mg), and then the reaction of the Grignard reagent with the halogenated organic silane compound or compound (1) is repeated a plurality of times to form an organosilicon compound having the structure shown in the following formula (2) (hereinafter also referred to as compound (2)). In formula (2), n represents the number of repetitions and is an integer of 2 or more.

[0049] [Chemical formula]

[0050] [Chemical formula]

[0051] When a halogen atom remains in the obtained organosilicon compound, when the organosilicon compound is mixed with an alcohol such as methanol, the remaining halogen-silicon moiety in the organosilicon compound reacts with methanol to form an alkoxylated organosilicon compound. For example, when the above compound (2) is reacted with an alcohol (R 3 OH; R 3 is an organic group), an alkoxylated organosilicon compound having a structure represented by the following formula (3) (hereinafter, also referred to as "compound (3)") is formed.

[0052] [Chemical formula]

[0053] In the reaction for forming the above compound (3), hydrogen halide (HY) is generated simultaneously with the formation of the alkoxylated organosilicon compound. Therefore, in this case, the content of the organolead compound in the liquid can be reduced without performing a treatment of externally adding and mixing hydrogen halide in the liquid. In this case, this reaction corresponds to the reaction for generating the above hydrogen halide.

[0054] The reactions for obtaining the above compounds (1) and (2) are preferably carried out in an organic solvent such as a hydrocarbon solvent, an ether solvent, or a chlorinated organic solvent, and more preferably an ether solvent. Examples of the ether solvent include diethyl ether, diisopropyl ether, dibutyl ether, tert-butyl methyl ether, 1,2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, or 1,4-dioxane. Among these, tetrahydrofuran is preferably used from the viewpoints of reaction control and ease of industrial availability. In addition, in order to obtain the above compound (3), when an alcohol is reacted to generate hydrogen halide, it is finally desirable to neutralize it, and it is preferable to add triethylamine, trimethylamine, sodium hydrogen carbonate, or a basic compound, etc. Among these, triethylamine is more preferable.

[0055] The conditions for the reaction to obtain the above compound (1) and the reaction to obtain the compound (2) are not particularly limited. For example, these reaction temperatures may be 0 to 60 °C, or 30 to 45 °C, etc., and the total reaction time of these reactions may be 1 to 6 hours, or 1 to 4 hours, etc. In addition, the conditions for the reaction of the above formula (3) are not particularly limited. For example, the reaction temperature may be 0 to 60 °C, or 15 to 30 °C, etc., and the reaction time may be 1 to 6 hours, or 1 to 2 hours, etc.

[0056] The inventors of the present invention further focused on the fact that the above compound (3) can also be synthesized by the following method. The following method is a method of synthesizing and purifying the compound (3) by reacting an alkoxysilane, and an organic halide with magnesium. Hereinafter, the above method is also referred to as the first method, and the following method is also referred to as the second method. Regarding the number of reaction steps for synthesizing the compound (3), since the second method has fewer steps than the first method, the second method is easier to react in a batch system, and there is a possibility of reducing the manufacturing cost. However, in the second method, since hydrogen halide is not generated, in order to remove the organolead compound, it is necessary to separately mix hydrogen halide with a liquid.

[0057] Organic halides such as alkyl halides, aryl halides, or alkenyl halides (R 1 X n ; R 1 is an organic group, X is independently a halogen atom, n is an integer of 1 or more), alkoxysilane (SiR 2 c (ОR 3 ) 4-c ; R 2is a hydrogen atom or an organic group, R 3 is an independent organic group, c is an integer from 0 to 3), and magnesium (Mg) are prepared and mixed. First, the organic halide reacts with magnesium to form a Grignard reagent (R 1 (X)MgX), and then the Grignard reagent reacts with an alkoxysilane, and a part of the OR 3 of the alkoxysilane is replaced by R 1 to produce compound (3).

[0058] The above reaction will be described more specifically with an example. For example, when R 1 X2 is used as the organic halide and Si(R 2 )(OR 3 )3 is used as the silane compound, first, a Grignard reagent (R 1 (X)MgX) is generated by the reaction of the organic halide and magnesium (Mg), and then the Grignard reagent reacts with a specific alkoxysilane, and at least a part of the (OR 3 ) of the alkoxysilane is replaced by R 1 to produce an organosilicon compound having the structure shown in the following formula (4) (hereinafter also referred to as compound (4)). Furthermore, by reacting compound (4) with magnesium (Mg), a Grignard reagent (XMgR 1 Si(R 2 )(OR 3 )2) is generated, and then the above compound (3) is generated by repeating the reaction of the Grignard reagent with an alkoxysilane or compound (4) a plurality of times.

[0059]

Chemical formula

[0060] Usually, since Mg used as a raw material contains Pb as an impurity, Pb is also contained in the liquid after the Grignard reaction. In this case, for example, when CH3Br is used as the above organic halide, tetramethyllead can be generated. Therefore, by incorporating hydrogen halide into the product solution after this reaction, the bond between the lead atom and the carbon atom in tetramethyllead can be cleaved, and the content of the organolead compound in the reaction solution or the product solution can be reduced.

[0061] In addition, in the above second method, the solvents that can be used in the reactions for obtaining the above compounds (1) and (2) can be similarly applied, an ether-based solvent is preferred, and tetrahydrofuran is more preferred.

[0062] The reaction conditions in the above second method are not particularly limited. For example, the reaction temperatures for the reactions for obtaining compounds (4) and (3) may both be 0 to 60°C, or 30 to 45°C, etc., and the total reaction time for the reactions for obtaining compounds (4) and (3) may be 1 to 6 hours, or 1 to 2 hours, etc.

[0063] The above R 1 is not particularly limited as long as it is an organic group, and may be a hydrocarbon group having 1 to 20 carbon atoms, may be a hydrocarbon group having 1 to 10 carbon atoms, may be a hydrocarbon group having 1 to 5 carbon atoms, or may be a hydrocarbon group having 1 to 3 carbon atoms. This hydrocarbon group may have a linear structure, may have a branched-chain structure, or may have a ring structure (alicyclic structure and / or aromatic ring structure). Also, the valence of this hydrocarbon is determined by the number of X's to which it binds. For example, if the number of X's is 1, it is monovalent; if the number of X's is 2, it is divalent; if the number of X's is 3, it is trivalent. Also, within the range where the effects of the present invention can be obtained, this hydrocarbon may have a substituent, and at least one carbon atom constituting the hydrocarbon may be substituted with a nitrogen atom, an oxygen atom, a silicon atom, a phosphorus atom, or a sulfur atom. For example, R 1 may have an ether structure, an amine structure, or a carbosilane structure, etc. The above R 2are not particularly limited as long as they are independently a hydrogen atom or an organic group, and the organic group may be a monovalent hydrocarbon group having 1 to 20 carbon atoms, a monovalent hydrocarbon group having 1 to 10 carbon atoms, a monovalent hydrocarbon group having 1 to 5 carbon atoms, a monovalent hydrocarbon group having 1 to 3 carbon atoms, The hydrocarbon group may be a 1-valent hydrocarbon group. This hydrocarbon group may have a straight chain structure, a branched chain structure, or a ring structure (alicyclic structure and / or aromatic ring structure). In addition, within the range in which the effects of the present invention can be obtained, this hydrocarbon may have a substituent, and at least one carbon atom constituting the hydrocarbon may be substituted with a nitrogen atom, an oxygen atom, a silicon atom, a phosphorus atom, or a sulfur atom, for example, R 2 may have an ether structure, an amine structure, a carbosilane structure, or the like. The above R 3 are not particularly limited as long as they are each an organic group capable of forming an alkoxy group, and may be a monovalent hydrocarbon group having 1 to 20 carbon atoms, a monovalent hydrocarbon group having 1 to 10 carbon atoms, a monovalent hydrocarbon group having 1 to 5 carbon atoms, or a monovalent hydrocarbon group having 1 to 3 carbon atoms. This hydrocarbon group may have a straight chain structure, a branched chain structure, or a ring structure (alicyclic structure and / or aromatic ring structure). Furthermore, within the range in which the effects of the present invention can be obtained, this hydrocarbon may have a substituent, and at least one carbon atom constituting the hydrocarbon may be substituted with a nitrogen atom, an oxygen atom, a silicon atom, a phosphorus atom, or a sulfur atom, and for example, R 3 may have an ether structure, an amine structure, a carbosilane structure, or the like. X is not particularly limited as long as it is a halogen atom, and is independently chlorine, bromine, or iodine. Y is not particularly limited as long as it is a halogen atom, and is independently chlorine, bromine, or iodine. The above n is not particularly limited and may be, for example, 2-20, 5-15, or 7-12. The above a is not particularly limited as long as it is an integer of 1 or more. For example, it may be 1-4, 1-3, or 1-2. b above is not particularly limited as long as it is an integer from 0 to 3. c above is not particularly limited as long as it is an integer from 0 to 3.

[0064] More specifically, as the organic halide R 1 X n there may be alkyl halides such as chloromethane, chloroethane, chloropropane, 2-chloropropane, 1-chloro-2-methylpropane, 2-chloro-2-methylpropane, 2-bromo-2-methylpropane, chlorobutane, bromobutane, chloropentane, chlorocyclopentane, chlorohexane, bromomethane, bromoethane, bromopropane, 2-bromopropane, 1-bromo-2-methylpropane, bromobutane, bromopentane, bromocyclopentane, bromohexane, iodomethane, iodoethane, iodopropane, 2-iodopropane, 1-iodo-2-methylpropane, iodopentane, iodocyclopentane, or iodohexane; alkenyl halides; aryl halides such as chlorobenzene, α-chlorotoluene, bromobenzene, α-bromotoluene, iodobenzene, or α-iodotoluene; alkylene dihalides such as dichloromethane, 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, 1,5-dichloropentane, dibromomethane, 1,2-dibromoethane, 1,3-dibromopropane, 1,4-dibromobutane, 1,5-dibromopentane, 1,3-diiodopropane, 1,4-diiodobutane, or 1,5-diiodopentane; or arylene dihalides such as o-dichlorobenzene, m-dichlorobenzene, p-dichlorobenzene, o-dibromobenzene, m-dibromobenzene, о-dibromobenzene, o-diiodobenzene, m-diiodobenzene, or p-diiodobenzene; etc. and the like can be mentioned.

[0065] As described above, the above-described method for removing an organolead compound can be applied to an embodiment including a synthesis process for synthesizing an alkoxylated organosilicon compound through at least a reaction process of performing a Grignard reaction.

[0066] [Polycondensation treatment] The method for producing an organosilicon compound may include a polycondensation treatment for polycondensing the organosilicon compound obtained by the above-described first method, second method, or the like. The method for performing the polycondensation is not particularly limited. For example, after reacting the organosilicon compound with water to perform hydrolysis, a polycondensation reaction by dehydration condensation using an acid catalyst can also be performed. After the polycondensation treatment, for example, liquid separation is performed, the acid catalyst is removed, dehydration is performed by a known method, impurities such as organolead are decomposed by UV treatment, and further, the impurities are removed by treating with an adsorbent by a known method to obtain the target product (organosilicon compound). The acid catalyst is not particularly limited, and examples thereof include oxalic acid and the like. The polycondensation treatment may be included in the treatment steps in the above-described method for removing an organolead compound.

[0067] The use of the organosilane compound produced by the above-described method for producing an organosilicon compound is not particularly limited, and it can be used, for example, in fields such as the field of materials engineering, the field of electronic materials, the field of pharmaceuticals, or the field of agriculture. In particular, an alkoxylated organosilicon compound, which is a kind of organosilicon compound, can not only be used as a material such as a surface modifier, an adhesion promoter, or a crosslinking agent itself, but also be used as a raw material for synthesizing a compound having a siloxane bond.

Examples

[0068] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0069] The experimental methods and evaluation methods in the examples and comparative examples are as follows.

[0070] [Evaluation] [Evaluation of lead concentration] 1 mL of the liquid obtained in the Examples or Comparative Examples described below was added to a Teflon (registered trademark) container, and the container was placed on a hot plate for heating to volatilize the organic solvent. Then, 1 mL of ultrapure water, 3 mL of nitric acid (60% by mass), and 2 mL of hydrofluoric acid (50% by mass) were dropped in, and heating was performed again for wet digestion. After that, heating was continued to dryness. After repeating wet digestion and drying until the organosilicon compound was completely decomposed, the remaining lead component was recovered with 0.2 mL of nitric acid (60%), and the solution was made up to 20 mL to obtain a measurement solution. The lead (Pb) concentration (mass%) in the measurement solution was quantified by ICP-MS (ICP-MS7900 manufactured by Agilent Technologies). The evaluation results are shown in the following tables.

[0071] <Synthesis of Organosilicon Compound> [Example 1] After putting 6.2 g of magnesium particles and 124.5 g of tetrahydrofuran into a reaction flask, a mixed solution of 32.3 g of 1,3-dibromopropane, 23.9 g of methyltrichlorosilane, and 26.7 g of tetrahydrofuran was gradually added, and then the reaction was carried out under reflux conditions to obtain an organosilicon compound (degree of polymerization: 8) represented by the following formula (5). 14.7 g of ethanol was added to the obtained reaction solution under reflux conditions to generate hydrogen chloride in the system. Then, it was stirred and held for 1 hour under reflux conditions to allow the organolead compound and hydrogen halide to react sufficiently. Then, 32.4 g of triethylamine was added to the reaction solution for neutralization, and then an oxalic acid aqueous solution was added to separate the organic phase and the aqueous phase. The organic phase was recovered, and the evaluation of the lead (Pb) concentration was carried out using the organic phase. The total molar amount of hydrogen halide with respect to the volume of the liquid after containing hydrogen halide was 0.72 mol / L.

[0072]

Chemical formula

[0073] [Comparative Example 1] After putting 6.2 g of magnesium particles and 124.5 g of tetrahydrofuran into the reaction flask, a mixed solution of 32.3 g of 1,3-dibromopropane, 23.9 g of methyltrichlorosilane, and 26.7 g of tetrahydrofuran was gradually added, and then the reaction was carried out under reflux conditions to obtain the organosilicon compound (degree of polymerization: 8) represented by the above formula (5). After adding 14.7 g of ethanol and 32.4 g of triethylamine to the obtained reaction solution, an oxalic acid aqueous solution was added to separate the solution into an organic phase and an aqueous phase, the organic phase was recovered, and the lead concentration was evaluated using the organic phase. In Comparative Example 1, after obtaining the organosilicon compound, since triethylamine is added together with ethanol, hydrogen chloride is generated by the reaction of the organosilicon compound and ethanol. However, since hydrogen chloride is neutralized by triethylamine simultaneously with its generation, the reaction between the organolead compound and hydrogen chloride does not occur.

[0074]

Table 1

[0075] It can be seen from Table 1 that in the method of Example 1 in which hydrogen chloride is generated in the liquid and the organolead compound is reacted with hydrogen chloride, the Pb concentration in the finally obtained liquid can be reduced as compared with the method of Comparative Example 1 in which triethylamine for neutralizing hydrogen chloride is added together with ethanol.

[0076] <Synthesis of Organosilicon Compound> [Example 2] After putting 26.3 g of magnesium particles and 926.3 g of tetrahydrofuran into a reaction flask, a mixed solution of 129.2 g of 1,3-dibromopropane, 95.7 g of methyltrichlorosilane, and 107.8 g of tetrahydrofuran was gradually added to obtain an organosilicon compound (degree of polymerization: 8) represented by the above formula (5). 59.0 g of ethanol was added to the obtained reaction solution to generate hydrogen chloride in the system. Then, it was stirred and held at 10 °C for 3 hours to sufficiently react the organolead compound with hydrogen chloride. Then, 129.5 g of triethylamine was added to the reaction solution for neutralization, an oxalic acid aqueous solution was added to separate it into an organic phase and an aqueous phase, and the organic phase was recovered. Next, the recovered organic phase was dehydrated with a dehydrating agent (magnesium sulfate), further treated with activated carbon, and then irradiated with ultraviolet rays for 1 hour using an ultraviolet irradiation device (Sen Special Light Source Co., Ltd.; reaction vessel VG300; water-cooled jacket JV-1Q; lamp UVL20PH-6, wavelength 254 nm; power supply UVB-20C) (ultraviolet intensity 3000 mW / cm 2 ). After that, 5% by mass of a dried chelating resin (manufactured by Organo Corporation; Orlite (registered trademark) DS-21) was added based on the liquid volume and mixed for 17 hours, and then the chelating resin was removed by filtration. The obtained liquid was used to evaluate the lead concentration. The total molar amount of hydrogen chloride with respect to the volume of the liquid after containing hydrogen chloride was , 0.46 mol / L.

[0077] [Comparative Example 2] After putting 26.3 g of magnesium particles and 926.3 g of tetrahydrofuran into the reaction flask, a mixed solution of 129.2 g of 1,3-dibromopropane, 95.7 g of methyltrichlorosilane, and 107.8 g of tetrahydrofuran was gradually added to obtain the organosilicon compound (degree of polymerization: 8) represented by the above formula (5). After adding 59 g of ethanol and 129.5 g of triethylamine to the obtained reaction solution, an oxalic acid aqueous solution was added to separate the solution into an organic phase and an aqueous phase, and the organic phase was recovered. Next, the recovered organic phase was dehydrated with a dehydrating agent (magnesium sulfate), further treated with activated carbon, and then subjected to ultraviolet irradiation and treatment using a chelating resin under the same conditions as in Example 2. After that, the chelating resin was removed by filtration. The obtained liquid was used to evaluate the lead concentration. In this Comparative Example 2, similar to Comparative Example 1 above, hydrogen chloride is generated by the reaction of the organosilicon compound and ethanol, but since hydrogen chloride is neutralized with triethylamine simultaneously with its generation, the reaction between the organolead compound and hydrogen chloride does not occur.

[0078]

Table 2

[0079] It can be seen from Table 2 that by generating hydrogen chloride in the liquid and reacting the organolead compound with hydrogen chloride, and then further performing ultraviolet irradiation on the liquid, the Pb concentration in the finally obtained liquid can be significantly reduced.

Claims

1. An organolead removal method for removing an organolead compound from a liquid containing an organolead compound, comprising a treatment step of containing hydrogen halide in the liquid and reacting the organolead compound with the hydrogen halide.

2. In the treatment step, the hydrogen halide is contained in the liquid by one or more treatments selected from a treatment of generating hydrogen halide by reacting a halogen-containing compound in the liquid and a treatment of mixing the liquid and the hydrogen halide. The organolead compound removal method according to Claim 1.

3. The total molar amount of the hydrogen halide with respect to the volume of the liquid after containing the hydrogen halide is 0.01 mol / L or more and 5.0 mol / L or less. The organolead compound removal method according to Claim 1 or 2.

4. The organolead compound removal method according to any one of Claims 1 to 3, comprising a purification step of removing a lead component contained in the liquid in at least one of during and after the treatment step.

5. The organolead compound removal method according to any one of Claims 1 to 4, comprising an irradiation step of irradiating the liquid with ultraviolet rays after the treatment step.

6. The organolead compound removal method according to any one of Claims 1 to 5, wherein the treatment step includes a reaction treatment of performing a Grignard reaction.

7. The organolead compound removal method according to Claim 6, comprising a synthesis treatment of synthesizing an alkoxylated organosilicon compound through at least the reaction treatment.

8. After the reaction treatment, a separation treatment of separating the organosilicon compound-containing liquid into an organic phase and an aqueous phase by mixing an aqueous solution containing an acid and the organosilicon compound-containing liquid. The organolead compound removal method according to Claim 6 or 7.

9. A method for producing an organosilicon compound, comprising a step of removing an organolead compound by the method for removing an organolead compound according to any one of claims 1 to 8.

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