Methods for making a sulfated polyaluminum chloride (PACS) flocculating agent solution, which may be aqueous, include neutralizing an aqueous sulfate-containing aluminum compound with an aqueous base to produce an aluminum hydroxide precipitate dispersed in a liquid, settling the aluminum hydroxide precipitate to create a supernatant liquid, removing an amount of the supernatant liquid to leave a remainder that contributes a selected concentration of sulfate to the PACS, and bringing the precipitate back into solution thereby forming the PACS flocculating agent. Also, methods for making a polyaluminum chloride (PAC) flocculating agent solution are disclosed that include neutralizing an aqueous chloride-containing aluminum compound with an aqueous base to produce an aluminum hydroxide precipitate dispersed in a liquid, settling the aluminum hydroxide precipitate to create a supernatant liquid, optionally, removing an amount of the supernatant liquid, and bringing the precipitate back into solution thereby forming the PAC flocculating agent.

The present invention relates to a process for modifying a layered double hydroxide (LDH), the process comprising, a. providing a water-wet layered double hydroxide of formula:

[M.sup.z+.sub.1-xM.sup.y+.sub.x].sup.a+(X.sup.n).sub.a/r.bH.sub.2O (1) wherein M and M are metal cations, z=1 or 2; y=3 or 4, x is 0.1 to 1, preferably x<1, more preferably x=0.1-0.9, b is greater than 0 to 10, X is an anion, r is 1 to 3, n is the charge on the anion X and a is determined by x, y and z, preferably a=z(1-x)+xy-2; b. maintaining the layered double hydroxide water-wet, and c. contacting the water-wet layered double hydroxide with at least one solvent, the solvent being miscible with water and preferably having a solvent polarity (P) in the range 3.8 to 9,
as well as to a layered double hydroxide prepared according to that process.

Activated aluminum sesquichlorohydrate (AASCH) powders prepared by (a) diluting the concentrated aluminum sesquichlorohydrate (ASCH) solution to from about 10% to about 25% by weight, (b) heating the diluted solution to obtain a Band III polymer concentration of at least about 20% and a Band IV polymer concentration of at least about 15%, (c) drying the heated solution to powders, and (d) optionally screen or light mill the powders to free flowing spherical particles are disclosed.

Aluminum chlorohydrate products comprise particles of aluminum chlorohydrate in fractured crystal form, the particles having a basicity in the range of 0% to about 85.6%, and a surface area to weight ratio of about 295 to about 705 m.sup.2/kg, inclusive of both endpoints and all numerical values therebetween, where the ratio is measured by laser diffraction. Methods of producing such products are also disclosed.

Activated aluminum sesquichlorohydrate (AASCH) powders and method of making are disclosed. The method of making the active comprises (a) diluting the concentrated aluminum sesquichlorohydrate (ASCH) solution to from about 10% to about 25% by weight and (b) heating the diluted solution to obtain a Band III polymer concentration of at least about 20% and a Band IV polymer concentration of at least about 15%, and (c) drying the heated solution to powders and (d) optionally screen or light mill the powders to free flowing spherical particles.

Methods for making an aqueous polyaluminum chloride (PAC) are disclosed that include adding an amount of a chloride-containing aluminum compound simultaneously with an amount of a base to a reaction vessel, mixing the two solutions in the reaction vessel, to produce a mixture, until a pH between 4.5 and 10 of the mixture is attained, maintaining the pH of the mixture between 4.5 and 10 during the mixing to produce an aluminum hydroxide precipitate dispersed in a liquid, allowing the aluminum hydroxide precipitate in the mixture to settle and creating a supernatant liquid, removing an amount of the supernatant liquid from the mixture to form a slurry, and adding a low- to mid-basicity polyaluminum chloride solution, an aluminum chloride solution, and/or a hydrochloric acid solution to the slurry to dissolve the aluminum hydroxide precipitate to form the aqueous polyaluminum chloride.

Methods for making an aqueous polyaluminum chloride (PAC) are disclosed that include adding an amount of a chloride-containing aluminum compound simultaneously with an amount of a base to a reaction vessel, mixing the two solutions in the reaction vessel, to produce a mixture, until a pH between 4.5 and 10 of the mixture is attained, maintaining the pH of the mixture between 4.5 and 10 during the mixing to produce an aluminum hydroxide precipitate dispersed in a liquid, allowing the aluminum hydroxide precipitate in the mixture to settle and creating a supernatant liquid, removing an amount of the supernatant liquid from the mixture to form a slurry, and adding a low- to mid-basicity polyaluminum chloride solution, an aluminum chloride solution, and/or a hydrochloric acid solution to the slurry to dissolve the aluminum hydroxide precipitate to form the aqueous polyaluminum chloride.

Aluminum chlorohydrate products include particles of aluminum chlorohydrate, in fractured crystal form, the particles having a basicity in the range of about 50% to about 85.6%, a bulk density of 40 to 65 pounds per cubic foot, and a mean particle size in the range of about 10 microns to about 15 microns. The particles may also have a surface area to weight ratio of about 295 to about 705 m.sup.2/kg, inclusive of both endpoints and all numerical values therebetween, where the ratio is measured by laser diffraction. Methods of producing such products are also disclosed.

Aluminum chlorohydrate products include particles of aluminum chlorohydrate, in fractured crystal form, the particles having a basicity in the range of about 50% to about 85.6%, a bulk density of 40 to 65 pounds per cubic foot, and a mean particle size in the range of about 10 microns to about 15 microns. The particles may also have a surface area to weight ratio of about 295 to about 705 m.sup.2/kg, inclusive of both endpoints and all numerical values therebetween, where the ratio is measured by laser diffraction. Methods of producing such products are also disclosed.

Methods for making a sulfated polyaluminum chloride (PACS) flocculating agent solution, which may be aqueous, include neutralizing an aqueous sulfate-containing aluminum compound with an aqueous base to produce an aluminum hydroxide precipitate dispersed in a liquid, settling the aluminum hydroxide precipitate to create a supernatant liquid, removing an amount of the supernatant liquid to leave a remainder that contributes a selected concentration of sulfate to the PACS, and bringing the precipitate back into solution thereby forming the PACS flocculating agent. Also, methods for making a polyaluminum chloride (PAC) flocculating agent solution are disclosed that include neutralizing an aqueous chloride-containing aluminum compound with an aqueous base to produce an aluminum hydroxide precipitate dispersed in a liquid, settling the aluminum hydroxide precipitate to create a supernatant liquid, optionally, removing an amount of the supernatant liquid, and bringing the precipitate back into solution thereby forming the PAC flocculating agent.