The present invention discloses the systems of producing calcium and magnesium carbonate from the Ca/Mg containing solution leached by a CO.sub.2-based hydrometallurgical process which includes: a precipitation reactor that the Ca/Mg containing leached solution is continuously added and fully mixed with the alkaline reagent at specific mole ratio into the precipitation reactor and the reactor also comprises a CO.sub.2 bubbling module where CO.sub.2 is captured and recirculated from the thermal decomposition process as needed; a solid-liquid separation unit that the treated slurry is treated by the solid-liquid separation unit to produce precipitated calcium and magnesium carbonate products where the recirculating water is recycled back into the precipitation reactor; a thermal decomposition unit that the calcium and magnesium carbonate products is calcined by the thermal decomposition unit to produce an alkaline reagent and the alkaline reagent is recycled back into the precipitation reactor for the next batch of reaction.

The present disclosure provides a method of making zeolite intergrowths. In one embodiment, the present disclosure provides a method of making an AEI-based material, including the steps of: preparing a mixture of water, an alumina source, a silica source, a CHA structure directing agent, and an AEI structure directing agent, wherein the molar ratio of the CHA structure directing agent to the AEI structure directing agent is from about 1:1 to about 1:15; heating the mixture at a temperature sufficient to promote formation of crystals; and calcining the crystals at a temperature of from about 450° C. to about 750° C. to obtain a product, wherein no halide-containing reagent is employed. The AEI-based materials of the present disclosure may find particular use in selective catalytic reduction of NO.sub.x in exhaust gas streams.

An activated carbon/palladium-gallium (Pd—Ga) liquid alloy composite catalyst, including a support and an active component supported on the support. The support is acid washed activated carbon. The active component is Pd—Ga liquid alloy. In the present invention, the active component Pd—Ga, present in the form of liquid alloy, forms a self-protective oxide layer. This protects acetylene from secondary reactions on the surface of the catalyst, inhibits or reduces acetylene to deeply hydrogenate to form ethane, thereby increasing ethylene selectivity. The present invention further provides a preparation method of the catalyst, where the catalyst of the present invention is prepared by immersion. The preparation method is simple and easy to operate. When the activated carbon/Pd—Ga liquid alloy composite catalyst provided by the present invention is used for acetylene hydrogenation to prepare ethylene, conversion rate of acetylene is as high as 99.8%, while the ethylene selectivity is as high as 98.9%.

A microspherical fluid catalytic cracking (FCC) catalyst includes a zeolite and alumina comprising a strong Lewis site density of less than 70 μ.Math.ηol/g.

Described herein is a system (100) for storage and releasing of carbon dioxide comprising at least one solids reactor (1), at least one compressor (7, 8) for compressing the carbon dioxide-containing gas or fluid, respectively, which is introduced through the inlet (3) of the solids reactor, wherein the compressor (7, 8) is constructed in such a way that it adiabatically expands the gas or fluid, respectively, depleted of carbon dioxide that is discharged from the reactor by means of the outlet (2) of the solids reactor, and at least one countercurrent recuperator (6), which is constructed for the heat exchange of the compressed exhaust gas or fluid, respectively, that contains carbon dioxide and the gas or fluid, respectively, depleted of carbon dioxide.

Described is furthermore a solids reactor for storage and releasing carbon dioxide, comprising a gas-tight or fluid-tight, respectively, housing, which has an interior, at least one inlet for feeding in fluids and at least one outlet for discharging of gases or fluids, respectively, wherein the interior of the housing is filled with at least two different solids, wherein one solid is provided for storing thermal energy and the other solid is provided for regenerative storage and releasing of carbon dioxide.

Furthermore described is a method for storage and releasing of carbon dioxide.

Method for preparing a catalyst comprising a bimetallic active phase made of nickel and copper, and a support comprising a refractory oxide, comprising the following steps: a step of bringing the support into contact with a solution containing a nickel precursor is carried out; a step of bringing the support into contact with a solution containing a copper precursor is carried out; a step of drying the catalyst precursor at a temperature lower than 250° C. is carried out; the catalyst precursor obtained is supplied to a hydrogenation reactor, and a step of reduction by bringing said precursor into contact with a reducing gas at a temperature lower than 200° C. for a period greater than or equal to 5 minutes and less than 2 hours is carried out.

A process for producing a catalyst including a) providing an uncalcined metal modified porous silica support wherein the modifier metal is selected from one or more of boron, magnesium, aluminium, zirconium, hafnium and titanium, wherein the modifier metal is present in mono- or dinuclear modifier metal moieties; b) optionally removing any solvent or liquid carrier from the modified silica support; c) optionally drying the modified silica support; d) treating the uncalcined metal modified silica support with a catalytic metal to effect adsorption of the catalytic metal onto the metal modified silica support; and e) calcining the impregnated silica support of step d). The invention extends to an uncalcined catalyst intermediate and a method of producing a catalyst by providing a porous silica support having isolated silanol groups.

A process comprising the following steps: a) calcination of a metal carbonate by combustion of a fuel in the presence of a mixture of oxygen, water vapour and carbon dioxide, to generate a metal oxide, water vapour, carbon dioxide and heat; b) using the heat generated to drive an oxygen generation reaction; and c) use of the oxygen generated in step b) in calcination step a). The use of the process on carbon dioxide sequestration and/or in oxygen generation.

A method is described for preparing an eggshell catalyst comprising the steps of: (i) preparing a calcined shaped alkaline earth metal aluminate catalyst support, (ii) treating the calcined shaped alkaline earth metal aluminate support with a gas containing water vapour to form a hydrated support, (iii) with or without an intervening drying step, impregnating the hydrated support with an acidic solution containing one or more catalytic metal compounds and drying the impregnated support, (iv) calcining the dried impregnated support, to form a calcined catalyst having a catalytic metal oxide concentrated at the surface of the support and (v) optionally repeating steps (ii), (iii) and (iv).

The present invention discloses a rare-earth-manganese/cerium-zirconium-based composite compound, a method for preparing the same, and a use thereof. The composite compound is of a core-shell structure with a general formula expressed as: A RE.sub.cB.sub.aO.sub.b-(1-A)Ce.sub.xZr.sub.(1-x-y)M.sub.yO.sub.2-z, wherein 0.1≤A≤0.3, preferably 0.1≤A≤0.2; a shell layer has a main component of rare-earth manganese oxide with a general formula of RE.sub.cMn.sub.aO.sub.b, wherein RE is a rare-earth element or a combination of more than one rare-earth elements, and B is Mn or a combination of Mn and a transition metal element, 1≤a≤8, 2≤b≤18, and 0.25≤c≤4; and a core has a main component of cerium-zirconium composite oxide with a general formula of Ce.sub.xZr.sub.(1-x-y)M.sub.yO.sub.2-z, wherein M is one or more non-cerium rare-earth elements, 0.1≤x≤0.9, 0≤y≤0.3, and 0.01≤z≤0.3. The composite compound enhances an oxygen storage capacity of a cerium-zirconium material through an interface effect, thereby increasing a conversion rate of a nitrogen oxide.