The present application pertains to methods for making alkali hydroxide, or alkali carbonates, or alkali bicarbonates, or alkaline—earth sulfates. In one embodiment, a material comprising an alkaline earth is converted to an alkaline earth sulfite or bisulfite and reacted with an alkali sulfate to form an alkaline earth sulfate and alkali sulfite or bisulfite. The alkali sulfite or bisulfite is converted into an alkali hydroxide, or an alkali carbonate, or an alkali bicarbonate. In another embodiment, ammonium carbonate or ammonium bicarbonate is reacted with an alkali sulfate, to form ammonium sulfate and an alkali carbonate or alkali bicarbonate. A material comprising an alkaline earth is converted to an alkaline earth sulfite or bisulfite and reacted with the ammonium sulfate to form an alkaline earth sulfate and ammonium sulfite or ammonium bisulfite. The ammonium sulfite or bisulfite is regenerated into ammonia, or ammonium hydroxide, or ammonium carbonate, or ammonium bicarbonate.

The present application pertains to methods for making alkali hydroxide, or alkali carbonates, or alkali bicarbonates, or alkaline—earth sulfates. In one embodiment, a material comprising an alkaline earth is converted to an alkaline earth sulfite or bisulfite and reacted with an alkali sulfate to form an alkaline earth sulfate and alkali sulfite or bisulfite. The alkali sulfite or bisulfite is converted into an alkali hydroxide, or an alkali carbonate, or an alkali bicarbonate. In another embodiment, ammonium carbonate or ammonium bicarbonate is reacted with an alkali sulfate, to form ammonium sulfate and an alkali carbonate or alkali bicarbonate. A material comprising an alkaline earth is converted to an alkaline earth sulfite or bisulfite and reacted with the ammonium sulfate to form an alkaline earth sulfate and ammonium sulfite or ammonium bisulfite. The ammonium sulfite or bisulfite is regenerated into ammonia, or ammonium hydroxide, or ammonium carbonate, or ammonium bicarbonate.

Systems and methods for generation of lime hydrate compounds and particularly highly reactive hydrated lime (HRH) with a reduced resistivity through the inclusion of a sodium compound generally in the slaking water used in generating the lime hydrate or HRH. The compound may then be used in systems which include a Electrostatic Precipitator (ESP) for SO.sub.2 mitigation without many of the associated problems in ESP performance.

Systems and methods for generation of lime hydrate compounds and particularly highly reactive hydrated lime (HRH) with a reduced resistivity through the inclusion of a sodium compound generally in the slaking water used in generating the lime hydrate or HRH. The compound may then be used in systems which include a Electrostatic Precipitator (ESP) for SO.sub.2 mitigation without many of the associated problems in ESP performance.

Provided is a method of preparing a metal oxide-silica composite aerogel and a metal oxide-silica composite aerogel having an excellent weight reduction property prepared by the method. The method comprises adding an acid catalyst to a first water glass solution to prepare an acidic water glass solution (step 1); adding a metal ion solution to the acidic water glass solution to prepare a precursor solution (step 2); and adding a second water glass solution to the precursor solution and performing a gelation reaction (step 3).

A phosphor in which an element represented by R.sub.δ is solid-solutionized in a phosphor host crystal represented by M.sub.α(L, A).sub.βX.sub.γ, wherein M is at least one type of element selected from Mg, Ca, Sr, Ba and Zn, L is at least one type of element selected from Li, Na and K, A is at least one type of element selected from Al, Ga, B, In, Sc, Y, La and Si, X is at least one type of element selected from O, N, F and Cl (where all of X being N is excluded), R is at least one type of element selected from Mn, Cr, Ti, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho and Yb, α, β, γ and δ satisfy α+β+γ+δ=9, 0.00<α≤1.30, 3.70≤β≤4.30, 3.70≤γ≤4.30, and 0.00<δ≤1.30.

A phosphor in which an element represented by R.sub.δ is solid-solutionized in a phosphor host crystal represented by M.sub.α(L, A).sub.βX.sub.γ, wherein M is at least one type of element selected from Mg, Ca, Sr, Ba and Zn, L is at least one type of element selected from Li, Na and K, A is at least one type of element selected from Al, Ga, B, In, Sc, Y, La and Si, X is at least one type of element selected from O, N, F and Cl (where all of X being N is excluded), R is at least one type of element selected from Mn, Cr, Ti, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho and Yb, α, β, γ and δ satisfy α+β+γ+δ=9, 0.00<α≤1.30, 3.70≤β≤4.30, 3.70≤γ≤4.30, and 0.00<δ≤1.30.

The present application pertains to processes producing oxides using a weak acid intermediate. In one embodiment a material comprising calcium carbonate is reacted with a solution comprising aqueous carboxylic acid to form a gas comprising carbon dioxide and a solution comprising aqueous calcium carboxylate. The solution comprising aqueous calcium carboxylate is reacted with sodium sulfate to form a solution comprising aqueous sodium carboxylate and a solid comprising calcium sulfate. The solution comprising aqueous sodium carboxylate is reacted with sulfur dioxide to form sodium sulfite and an aqueous carboxylic acid. The sodium sulfite is separated from said aqueous carboxylic acid and reacted to form a solid comprising calcium sulfite which is decomposed to form calcium oxide and sulfur dioxide.

The present application pertains to processes producing oxides using a weak acid intermediate. In one embodiment a material comprising calcium carbonate is reacted with a solution comprising aqueous carboxylic acid to form a gas comprising carbon dioxide and a solution comprising aqueous calcium carboxylate. The solution comprising aqueous calcium carboxylate is reacted with sodium sulfate to form a solution comprising aqueous sodium carboxylate and a solid comprising calcium sulfate. The solution comprising aqueous sodium carboxylate is reacted with sulfur dioxide to form sodium sulfite and an aqueous carboxylic acid. The sodium sulfite is separated from said aqueous carboxylic acid and reacted to form a solid comprising calcium sulfite which is decomposed to form calcium oxide and sulfur dioxide.

The present application pertains to processes producing oxides using a weak acid intermediate. In one embodiment a material comprising calcium carbonate is reacted with a solution comprising aqueous carboxylic acid to form a gas comprising carbon dioxide and a solution comprising aqueous calcium carboxylate. The solution comprising aqueous calcium carboxylate is reacted with sodium sulfate to form a solution comprising aqueous sodium carboxylate and a solid comprising calcium sulfate. The solution comprising aqueous sodium carboxylate is reacted with sulfur dioxide to form sodium sulfite and an aqueous carboxylic acid. The sodium sulfite is separated from said aqueous carboxylic acid and reacted to form a solid comprising calcium sulfite which is decomposed to form calcium oxide and sulfur dioxide.