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A collapsed composition is described which is substantially composed of microcrystallites collectively of the formula: M2m2+Al2-pMp3+TrO7+r.s where M2+is a divalent metal, M3+is a trivalent metal, and T is vanadium, tungsten, or molybdenum. The microcrystallites are so small as to be undetectable th

A collapsed composition is described which is substantially composed of microcrystallites collectively of the formula: M2m2+Al2-pMp3+TrO7+r.s where M2+is a divalent metal, M3+is a trivalent metal, and T is vanadium, tungsten, or molybdenum. The microcrystallites are so small as to be undetectable through conventional x-ray diffraction techniques, yet high resolution electron microscopy reveals that a substantial portion of the microcrystallites are composed of a solid solution having aluminum oxide molecularly dispersed in a divalent metal monoxide crystal structure. Another portion of the microcrystallites are constituted by a spinel phase. The collapsed composition is suitable as a sulfur oxide absorbent, having comparatively high capacity and comparatively fast absorption and desorption rates. The collapsed composition may be produced by heat treating a layered mixed hydroxide clay having interlayer anions in monometalate form. A sulfur oxide separation process is also presented. The process can be operated cyclicly and integrated with any of several well-known fluidized bed catalytic cracking processes.

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An anionic layered mixed hydroxide composition of the formula: [Figure] where M2+is a divalent metal selected from the group consisting of magnesium, calcium, zinc, barium and strontium; x is about 1.1 to about 3.5; n is about 0.01 to about 0.4; M3+is a trivalent metal selected from the group cons

An anionic layered mixed hydroxide composition of the formula: [Figure] where M2+is a divalent metal selected from the group consisting of magnesium, calcium, zinc, barium and strontium; x is about 1.1 to about 3.5; n is about 0.01 to about 0.4; M3+is a trivalent metal selected from the group consisting of cerium, lanthanum, iron, chromium, vanadium, and cobalt; J is VO3, HVO4, VO4, V2O7, HV2O7, V3O9, V4O12, WO4 or MoO4; v is the net ionic charge associated with J; k is about 0.01 to less than 2; A is selected from the group consisting of CO3, OH, SO3, SO4, Cl, and NO3; q is the net ionic charge associated with A; and m is a positive number. A process for manufacturing a composition which comprises: blending water, about two molar parts of a salt of a divalent metal selected from the group consisting of magnesium, calcium, zinc, strontium and barium, and about one molar part in sum of an aluminum salt and a salt of a trivalent metal selected from the group consisting of cerium, lanthanum, iron, chromium, vanadium, and cobalt to produce a mixture; heating the mixture to a temperature in the range of about 50°to about 100°C. for at least about one hour; recovering from the mixture an anionic layered mixed hydroxide having anions selected from the group consisting of CO3, OH, SO3, SO4, Cl and NO3; calcining the recovered layered mixed hydroxide for not less than about one hour at a temperature of about 450°C. or hotter, to produce a dehydrated material which is essentially devoid of the anions selected from the group consisting of CO3, OH, SO3, SO4, Cl and NO3; mixing the dehydrated material with an aqueous solution including about 0.01 to less than two molar parts of a metalate salt containing vanadate, tungstenate, or molybdate anions to produce a slurry, the solution also including an amount of an alkalinity control agent appropriate to stabilize the vanadate, tungstenate, or molybdate anions in monometalate, dimetelate, trimetalate or tetrametalate form; and recovering solids from the slurry and calcining the solids to produce an at least partially collapsed composition suitable for use as a sulfur oxide absorbent which is substantially composed of solid solution microcrystallites having aluminum oxide dispersed in an oxide of the divalent metal and of spinel base microcrystallites, each of the microcrystallites having the greatest linear dimension in the range of about 0.1 to about 30 nanometers.