343results about "Hydrotalcite" patented technology

The present invention provides a lithium-air secondary battery that is capable of effectively preventing deterioration of an alkaline electrolytic solution, air electrode, and negative electrode and has a long life and high long-term reliability. The lithium-air secondary battery comprises an air electrode 12 functioning as a positive electrode, an anion exchanger 14 provided in close contact with one side of the air electrode and composed of a hydroxide-ion conductive inorganic solid electrolyte, a separator 16 provided away from the anion exchanger and composed of a lithium-ion conductive inorganic solid electrolyte, a negative electrode 18 provided so as to be capable of supplying and receiving lithium ions to and from the separator and comprising lithium, and an alkaline electrolytic solution 20 filled between the anion exchanger and the separator.

The present invention is directed to methods for reducing SOx, NOx, and CO emissions from a fluid stream comprising contacting said fluid stream with a compound comprising magnesium and aluminum and having an X-ray diffraction pattern displaying at least a reflection at a two theta peak position at about 43 degrees and about 62 degrees, wherein the ratio of magnesium to aluminum in the compound is from about 1:1 to about 10:1. In one embodiment, the ratio of magnesium to aluminum in the compound is from about 1:1 to about 6:1. In one embodiment, the ratio of magnesium to aluminum in the compound is from about 1.5:1 to about 10:1. In another embodiment, the invention is directed to methods wherein the ratio of magnesium to aluminum in the compound is from about 1.5:1 to about 6:1.

Anionic clay compounds such as hydrotalcite-like compounds can be made by a process wherein a non-hydrotalcite-like compound (or a hydrotalcite-like compound) are heat treated and then hydrated to form hydrotalcite-like compounds having properties (e.g., increased hardness and/or density) that differ from those of hydrotalcite-like compounds made by prior art methods wherein non-hydrotalcite-like compounds (or hydrotalcite-like compounds) are not similarly heat treated and hydrated to form such hydrotalcite-like compounds.

The invention has for its object to provide a preparation method for preparing an anion-exchangeable LDH by decarbonation of a carbonate ion type LDH, which makes sure de carbonation is implemented with safety in a continuous manner while crystal shape, crystal structure and crystallinity are kept intact.

The invention provides a preparation method for preparing an anion-exchangeable, layered double hydroxide wherein a carbonate ion type layered double hydroxide (LDH) having a composition represented by a general formula: Q_xR(OH)_z(CO₃²⁻)_0.5-y/2(X⁻)_y.nH₂O where x is indicative of a numeral range of 1.8≦x≦4.2; z is indicative of 2(x+1); y is indicative of a minimum value of at least 0 that increases to less than 1 when anions (X⁻) remain or a part of anions is introduced; Q is a divalent metal ion; R is a trivalent metal ion; and n is 2±2 is used as a starting material, and y in said general formula increases to a maximum of 1 by substitution of a minus monovalent anion (X⁻¹) at a carbonate ion site thereby implementing substitution, characterized in that the starting material is dispersed in an aqueous solution mixed with a salt containing minus monovalent anions (X⁻) in an amount enough for substitution at the carbonate ion site while said aqueous solution is kept at a pH (hydrogen ion exponent) of greater than 4 to less than 7.

A process for treating a natural or wastewater containing dissolved Mg or dissolved Al comprising the steps of adding at least one Mg-containing compound or at least one Al-containing compound to the natural or wastewater to thereby form a layered double hydroxide (LDH) containing Mg and Al as predominant metal species in a lattice of the LDH. The LDH may comprise hydrotalcite. The AL-containing compound may be aluminate or aluminium hydroxide derived from the Bayer process or from an alumina refinery.

LDH-osmate of the formula [MII(1-x)MIIIx(OH)2][OsO42-]x/2.zH2O wherein MII is a divalent cation selected from the group consisting of Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+ and Ca2+ and MIII is a trivalent ion selected from the group consisting of Al3+, Cr3+, Mn3+, Fe3+ and Co3+, and x is the mole fraction having integral value ranging from 0.2 to 0.33, and z is the number of water molecules and ranges from 1 to 4, useful as, a catalyst, and a process for the preparation thereof and use thereof to manufacture vicinal diols.

Disclosed is a layered double hydroxide capable of delamination in water comprising a plurality of basal layers of a double hydroxide of Formula:

M(II)_1-xM(III)_x(OH)₂

wherein M(II) is Mg, Zn or a combination thereof, M(III) is Al, and x is 0.2 to 0.33 and a plurality of intercalated layers between each adjacent basal layers of Mg acetate, Zn acetate or Ce acetate and water of intercalation. A process for producing the layered double hydroxide is also disclosed. The layered double hydroxide find use as an vehicle component or an anti-corrosive pigment of water-based protective coatings for metallic substrates, and as a humectant or a stabilizing agent for cosmetic preparations such as lotions, creams or foundations.

The present invention is directed to a process for the preparation of a doped anionic clay. In said process a trivalent metal source is reacted with a divalent metal source, at least one of the metal sources being either doped boehmite, doped MgO or doped brucite, to obtain a doped anionic clay. Suitable dopants are compounds containing elements selected from the group of alkaline earth metals (for instance Ca and Ba), alkaline metals, transition metals (for example Co, Mn, Fe, Ti, Zr, Cu, Ni, Zn, Mo, W, V, Sn), actinides, rare earth metals such as La, Ce, and Nd, noble metals such as Pt and Pd, silicon, gallium, boron, titanium, and phosphorus.

The invention provides the organic anion intercalation hydrotalcite containing double bond, whose chemical formula is [M2+1-xM3+x(OH)2]An-x/níñmH2O. An is organic anion intercalation hydrotalcite containing double bond, such as maleic acid group, acroleic acid group, butenoic acid group, and so on. Because the double bond of organic anion intercalation hydrotalcite can react with the conjugate double bonds produced by PVC, the long-term thermal stability of PVC is improved markedly. The hydrotalcite can effectively improve the effectively of PVC.

A process is disclosed for preparing and self-assembly of nanobinary and ternary metal oxy/hydroxides with high surface area and 1-10 nm size by aerogel procedure, involving homogenization of metal organic precursors in solvent mixture, controlled hydrolysis, gelation, hydrothermal treatment and finally supercritical drying of solvent.

The invention relates to a cyclodextrin pillared hydrotalcite film which grows in a way of being perpendicular to a basis and a preparation method thereof, belonging to the technical field of organic-inorganic composite materials and preparation thereof. The chemical formula of pillared hydrotalcite is [(M<2+><1-x> (M<3+><x> (OH)2<x+> (CMCD <n->) x/n question mark mH2O. The preparation method comprises the steps as follows: aluminium flakes are firstly anodized under the condition of constant voltage; divalent metal salts are taken and weighed respectively, cyclodextrin decorated with negative ion and NH4NO3 are dissolved in de-ionized water to prepare into reaction synthetic solution, and then ammonia is used for adjusting the pH of the reaction synthetic solution to a value between 5.9 and 8.5. Anodized alumina/aluminium-base flakes are vertically hung in the reaction synthetic solution to carry out reaction at certain temperature for a certain time to prepare the cyclodextrin pillared hydrotalcite film. The invention has advantages that: the cyclodextrin pillared hydrotalcite film prepared by an in-situ growth technology is fixed on an aluminium basis, thus realizing the immobilization and unitization of the hydrotalcite; besides, the hydrotalcite prepared has certain mechanical strength, which provides great convenience to the application of cyclodextrin pillared hydrotalcite materials both in production and life.

The invention discloses a method for preparing two-dimensional single-layer magnesium-aluminum layered double-metal hydroxide nanosheets. The method comprises the following steps: (a) dissolving a magnesium salt and an aluminum salt in formamide, thereby forming a liquid A, wherein a molar ratio of magnesium ions in the magnesium salt to aluminum ions in the aluminum salt is 2:1; (b) mixing a strong alkaline hydroxide with the liquid A, thereby obtaining a colloidal mixed liquid, wherein the molar ratio of the strong alkaline hydroxide to the aluminum ions in the aluminum salt is (9-15):1; and (c) carrying out a hydrothermal reaction on the colloidal mixed liquid obtained in the step (b), thereby obtaining the two-dimensional single-layer magnesium-aluminum layered double-metal hydroxide nanosheets, wherein the two-dimensional single-layer magnesium-aluminum layered double-metal hydroxide nanosheets are dispersed in the solvent formamide, and forming the dispersion of the two-dimensional single-layer magnesium-aluminum layered double-metal hydroxide nanosheets, wherein the temperature of the hydrothermal reaction is 20-70 DEG C, and the reaction time is 2-72 hours. The method is low in cost, simple in preparation process, short in production cycle and suitable for industrial production, and the solvent can be recycled.

The present invention is a manufacturing method for an anion-layered double hydroxide intercalation compound that uses metal hydroxides as the stating material of the layered double hydroxides (LDH) which are the host material and allows sterically complicated and large-size anion compounds to be used as the guest material, and it has the characteristics such that a reaction mixture of the metal hydroxides and anion compound is heated and hydrothermally reacted in the absence of anion components other than the anion compound of the guest material. In addition, the present invention pertains to an anion-layered double hydroxide intercalation compound that uses bile acid as the anion compound of the guest material, which is effective as the carrier of medical drugs or as the absorbent of physiological active materials.

A process for preparing a catalyst comprising palladium supported on a carrier via a layered precursor, comprising the following steps: (1) synthesis of hydrotalcite layered precursor which comprises promoting metal element and aluminium on the surface of the carrier of Al₂O₃ microspheres, the atoms of the promoting metal and aluminium being highly dispersed by each other and bonded firmly to the carrier due to the crystal lattice positioning effect of the hydrotalcite crystal; (2) introduction of palladium into the carrier through impregnation; (3) drying; and (4) calcination and reduction with H₂, the hydrotalcite layered precursor being converted into a composite oxide which consists of oxides of the promoting metal and aluminium, and the promoting metal element and aluminium being highly dispersed by each other and being able to separate and disperse the mainly active palladium element loaded later. The process has the advantages of improving the catalytic performance of the catalyst, enhancing the stability of the catalyst, and achieving the object of reducing the consumption of the precious metal-palladium.

The invention discloses a method for preparing a hydrotalcite material adopting a multi-shell hollow structure. The method comprises the following steps: firstly, preparing a metal organic framework material (MOF-1), epitaxially growing to obtain MOF-1@MOF-2, and then etching by a sacrificial template method to obtain single-layer hollow hydrotalcite (LDH); with MOF as a seed crystal, epitaxiallygrowing to obtain MOF-1@MOF-2@MOF-1@MOF-2, and then etching by the sacrificial template method to obtain double-layer hollow LDH; repeating the epitaxially growing step to obtain multi-shell MOF, andfinally etching to obtain the LDH adopting the multi-shell hollow structure. The method is simple, easy to implement, mild in condition and high in safety; by the method, the multi-shell hollow LDH can be obtained; the method has a wide application prospect.

The invention discloses a preparation method of ultrathin modified hydrotalcite and an application thereof to a rubber gas barrier thin film material. Firstly, coprecipitation is used for preparing ultrathin hydrotalcite with a high length diameter ratio, surface modification is carried out, spin coating method technology is used, the ultrathin modified hydrotalcite and rubber are compounded in order to form a film, and finally the gas barrier thin film material is prepared by compounding the ultrathin modified hydrotalcite and the rubber. The ultrathin hydrotalcite with a nanometer sheet shaped structure has high length diameter ratio, and can be used as a filler for substantially prolonging diffusion path of oxygen molecules in a thin film material; surface modification of hydrotalcite can improve interfacial compatibility between hydrotalcite and rubber, and reduce free volume, so that the composite thin film materials has excellent gas barrier performance, good heat stability and mechanical performance. The method has wide source, low cost, and simple preparation, and accords with environmental protection requirements; and the method has wide application prospects in the fields of automobile industry, outdoor packaging and aerospace industry.

Provided is a method of forming a layered double hydroxide (LDH) dense membrane on the surface of a porous substrate. The LDH dense membrane is composed of an LDH represented by the formula: M²⁺_1-xM³⁺_x(OH)₂Aⁿ⁻_x/n·mH₂O where M²⁺ represents a divalent cation. M³⁺ represents a trivalent cation, Aⁿ⁻ represents an n-valent anion, n is an integer of 1 or more, and x is 0.1 to 0.4. This method includes (a) providing a porous substrate, (b) evenly depositing, on the porous substrate, a nucleation material capable of providing a nucleus from which the crystal growth of the LDH starts; and (c) hydrothermally treating the porous substrate in an aqueous stock solution containing a constituent element of the LDH to form the LDH dense membrane on the surface of the porous substrate. The method of the present invention can form a highly-densified LDH membrane evenly on the surface of a porous substrate.

The present invention relates to mixed metal compounds having pharmaceutical activity, especially as phosphate binders. It also extends to methods of manufacture of those compounds, as well as to pharmaceutical compositions containing such compounds. It further relates to their pharmaceutical use. In particular, the present invention relates to use of compounds of Formula (I): M^II_1-aM^III_a wherein M is at least one bivalent metal (i.e. with two positive charges); M1 is at least one trivalent metal (i.e. with three positive charges); and 1>a>0.4.

The present invention is a novel hydrotalcite compound that is environmentally friendly and exhibits an excellent metal corrosion inhibiting effect by the addition of a small amount thereof, and an inorganic ion scavenger employing same; the hydrotalcite compound is represented by Formula (1), has a hydrotalcite compound peak in the powder X-ray diffraction pattern, the peak intensity at 2θ=11.4° to 11.7° being at least 3,500 cps, and has a BET specific surface area of greater than 30 m²/g.

Mg_aAl_b(OH)_c(CO₃)_d·nH₂O  (1)

In Formula (1), a, b, c, and d are positive numbers and satisfy 2a+3b−c−2d=0. Furthermore, n denotes hydration number and is 0 or a positive number.

The invention relates to the field of lithium carbonate preparation, in particular to a method for extracting lithium from brine to prepare battery-grade lithium carbonate by an ion exchange method. The method includes the steps of 1), removing magnesium by a coprecipitation method; 2), adsorbing to extract the lithium by a manganese adsorbent; 3), preparing the battery-grade lithium carbonate, namely adding alkaline liquor into a desorption solution in the step 2), regulating a pH value to 7-12, producing manganese hydroxide precipitate, filtering the manganese hydroxide precipitate, concentrating filtrate until the lithium content reaches 20-30 g/L, filtering to remove sodium chloride, adding a saturated sodium carbonate solution to react, filtering, and subjecting filter cakes to water scrubbing so as to obtain the battery-grade lithium carbonate. The method has the advantages that hydrotalcite is obtained after magnesium removal, so that the problem of recycling the magnesium in the brine is solved; the content of various impurity ions in the desorption solution can be controlled effectively by removing the magnesium and extracting the lithium by adsorption sequentially, and then the battery-grade lithium carbonate is prepared.