The present invention relates to alumina flakes having a defined thickness and particle size distribution and to their use in varnishes, paints, automotive coatings, printing inks, masterbatches, plastics and cosmetic formulations and as substrate for effect pigments.

Described is a method for extracting lithium from salt lake brine and simultaneously preparing aluminum hydroxide. This method includes a. adding an aluminum salt to the brine, adding an alkali solution, then subjecting to crystallization reaction and solid-liquid separation to obtain lithium-containing brine; b. evaporating and concentrating the lithium-containing brine, adding an aluminum salt, adding an alkali solution dropwise to perform a co-precipitation reaction and solid-liquid separation to obtain a lithium-containing layered material filter cake, wherein in steps a and b, the alkali solution is an alkali solution free of carbonate ion; c. dispersing the lithium-containing layered material filter cake in deionized water to form a suspension slurry, then adjusting the pH value of the suspension slurry so as to carry out a lithium deintercalation reaction; d. filtering to obtain aluminum hydroxide filter cake; e. washing the aluminum hydroxide filter cake with deionized water and drying.

Described is a method for extracting lithium from salt lake brine and simultaneously preparing aluminum hydroxide. This method includes a. adding an aluminum salt to the brine, adding an alkali solution, then subjecting to crystallization reaction and solid-liquid separation to obtain lithium-containing brine; b. evaporating and concentrating the lithium-containing brine, adding an aluminum salt, adding an alkali solution dropwise to perform a co-precipitation reaction and solid-liquid separation to obtain a lithium-containing layered material filter cake, wherein in steps a and b, the alkali solution is an alkali solution free of carbonate ion; c. dispersing the lithium-containing layered material filter cake in deionized water to form a suspension slurry, then adjusting the pH value of the suspension slurry so as to carry out a lithium deintercalation reaction; d. filtering to obtain aluminum hydroxide filter cake; e. washing the aluminum hydroxide filter cake with deionized water and drying.

A nano platelet gibbsite treated with compound of formula (OR.sup.a).sub.3Si—R or of formula R.sup.c—COOH wherein R.sup.a equal to or different from each other is a C.sub.1-C.sub.10 alkyl radical; R.sup.b is a C.sub.5-C.sub.30 hydrocarbon radical and R.sup.c is a C.sub.5-C.sub.30 hydrocarbon radical is used as a catalyst support.

A surface-modified iron-based oxide magnetic particle powder has good solid-liquid separation property in the production process, has good dispersibility in a coating material for forming a coating-type magnetic recording medium, has good orientation property, and has a small elution amount of a water-soluble alkali metal, and to provide a method for producing the surface-modified iron-based oxide magnetic particle powder. The surface-modified iron-based oxide magnetic particle powder can be obtained by neutralizing a solution containing dissolved therein a trivalent iron ion and an ion of the metal, by which the part of Fe sites is to be substituted, with an alkali aqueous solution, so as to provide a precursor, coating a silicon oxide on the precursor, heating the precursor to provide e-type iron-based oxide magnetic powder, and adhering a hydroxide or a hydrous oxide of one kind or two kinds of Al and Y thereto.

A surface-modified iron-based oxide magnetic particle powder has good solid-liquid separation property in the production process, has good dispersibility in a coating material for forming a coating-type magnetic recording medium, has good orientation property, and has a small elution amount of a water-soluble alkali metal, and to provide a method for producing the surface-modified iron-based oxide magnetic particle powder. The surface-modified iron-based oxide magnetic particle powder can be obtained by neutralizing a solution containing dissolved therein a trivalent iron ion and an ion of the metal, by which the part of Fe sites is to be substituted, with an alkali aqueous solution, so as to provide a precursor, coating a silicon oxide on the precursor, heating the precursor to provide e-type iron-based oxide magnetic powder, and adhering a hydroxide or a hydrous oxide of one kind or two kinds of Al and Y thereto.

The present disclosure relates to a method for extracting lithium from salt lake brine and simultaneously preparing aluminum hydroxide. This method includes: a. adding an aluminum salt to the brine to obtain a mixed salt solution A, adding an alkali solution to the mixed salt solution A for co-precipitation reaction, then subjecting to crystallization reaction and solid-liquid separation at the end of the reaction to obtain magnesium-aluminum hydrotalcite solid product and lithium-containing brine, wherein in step a, the alkali solution is an alkali solution free of carbonate ion; b. evaporating and concentrating the lithium-containing brine to obtain a lithium-rich brine, adding an aluminum salt to the lithium-rich brine to obtain a mixed salt solution B, adding an alkali solution dropwise to the mixed salt solution B to perform a co-precipitation reaction and solid-liquid separation after the end of the reaction to obtain a lithium-containing liquid and a lithium-containing layered material filter cake, wherein in step b, the alkali solution is an alkali solution free of carbonate ion; c. dispersing the lithium-containing layered material filter cake in deionized water to form a suspension slurry, then adjusting the pH value of the suspension slurry so as to carry out a lithium deintercalation reaction; d. filtering the slurry obtained after the lithium deintercalation reaction to obtain a lithium-containing solution and aluminum hydroxide filter cake; e. washing the aluminum hydroxide filter cake with deionized water and drying to obtain aluminum hydroxide solid.

The present disclosure relates to a method for extracting lithium from salt lake brine and simultaneously preparing aluminum hydroxide. This method includes: a. adding an aluminum salt to the brine to obtain a mixed salt solution A, adding an alkali solution to the mixed salt solution A for co-precipitation reaction, then subjecting to crystallization reaction and solid-liquid separation at the end of the reaction to obtain magnesium-aluminum hydrotalcite solid product and lithium-containing brine, wherein in step a, the alkali solution is an alkali solution free of carbonate ion; b. evaporating and concentrating the lithium-containing brine to obtain a lithium-rich brine, adding an aluminum salt to the lithium-rich brine to obtain a mixed salt solution B, adding an alkali solution dropwise to the mixed salt solution B to perform a co-precipitation reaction and solid-liquid separation after the end of the reaction to obtain a lithium-containing liquid and a lithium-containing layered material filter cake, wherein in step b, the alkali solution is an alkali solution free of carbonate ion; c. dispersing the lithium-containing layered material filter cake in deionized water to form a suspension slurry, then adjusting the pH value of the suspension slurry so as to carry out a lithium deintercalation reaction; d. filtering the slurry obtained after the lithium deintercalation reaction to obtain a lithium-containing solution and aluminum hydroxide filter cake; e. washing the aluminum hydroxide filter cake with deionized water and drying to obtain aluminum hydroxide solid.

A sparsely pillared organic-inorganic hybrid compound is provided. The sparsely pillared organic-inorganic hybrid compound includes: two inorganic material layers, each extending in one direction and facing each other; and an organic material layer disposed between the two inorganic material layers, wherein each of the inorganic material layers has a gibbsite structure in which a divalent metal cation is doped to an octahedral site, and the organic material layer includes a plurality of pillar portions, each of which is chemically bound to each of the two inorganic material layers such that the two inorganic material layers are connected to each other.

Disclosed herein are system and methods to effectively leach coal ash with hydrochloric acid and separate an insoluble silica product and then selectively precipitate, from the leachate, a number to value-added, strategic, marketable products using a hydroxide reagent. The resulting precipitated products include iron, aluminum, magnesium, calcium, and a mixture of rare earth elements and transition metals. These can be separated as hydroxides or converted to oxides or carbonates. Using hydrochloric acid for leaching and converting the chloride to sodium chloride in the final step results in practically no waste for this process. The silica can be further purified using sodium hydroxide fusion or caustic leach methods and some minor streams from this process are recycled to minimize any waste stream. These systems and methods can be applied to a number of other industrial waste products such as red mud from the aluminum process, slag from steel furnaces, mine tailings, and other metal-bearing waste streams.