32results about How to "Increase the number of active centers" patented technology

The invention relates to a loaded type nickel-based catalyst used for slurry bed methanation, and a preparation method and an application thereof. The loaded type nickel-based catalyst is composed of, by weight, 10-40 wt% of NiO, 56-90 wt% of a carrier and 0-4 wt% of an auxiliary agent. The loaded type nickel-based catalyst is prepared by the steps of preparing a soluble salt solution of 0.5-1.3 g/mL nicdel nitrate and the auxiliary agent; adding a catalyst carrier and a soluble organic fuel to the salt solution in sequence; impregnating for 6-24 h while stirring; heating the solution for concentration in a water bath with a temperature of 60-90 DEG C after finishing the impregnation, or heating for igniting the solution at a temperature of 300-700 DEG C directly; collecting the combustion residue powder, grinding the powder and granulating, and reducing for 2-6 h with a reducing gas on a fixed bed at a temperature of 500-700 DEG C. The loaded type nickel-based catalyst has a slurry bed methanation process, and has the advantages of good and stable catalytic performance, and can be used for large-scale industrialization.

The invention discloses a precious metal methanation catalyst prepared by using a solution combustion method, which comprises the following components in percentage by weight: 1-10% of precious metal oxides and 90-99% of a carrier. The precious metal methanation catalyst disclosed by the invention has the advantages that the catalyst is applicable to a trace CO methanation process, and stable in catalytic performance.

The invention provides a supported precious metal methanation catalyst, comprising, by weight, 0.5 to 10% of a precious metal oxide and 90 to 99.5% of a carrier. The catalyst has the advantages of applicability to fixed-bed microscale CO methanation and stable catalytic performance.

The invention provides a reforming protective agent. Acidified pseudoboehmite and an acidified molecular sieve are taken as a common carrier under the synergistic effect, uniform dispersion of active ingredients such as manganese oxide and ferric oxide is promoted, the pore channel structure of the carrier can be optimized, the pore size, pore volume and specific surface area are increased, more vacant orbits and active centers are formed in the space structure of the carrier, the components further comprise catalyst wastes, and the mechanical strength of the carrier can be improved. Meanwhile, the vacant orbits and active centers in the structures of the acidified pseudoboehmite and an acidified molecular sieve can be coordinated with the catalyst wastes and active ingredients in the manganese oxide, the active center sites of the catalyst are improved, and the reaction is promoted. Therefore, according to the reforming protective agent disclosed by the invention, the mechanical strength is improved, and the protective agent has the advantages that the desulfurization reaction activity is high, the desulfurization efficiency is high, the service life of the catalyst is long, and side reactions can be effectively avoided.

The invention discloses an in-situ level nano selenium carbon based mercury removal adsorbent material and a preparation method and application thereof. Sulfur dioxide gas is introduced into a selenium-loaded carbon based adsorbent material to prepare the in-situ level nano selenium carbon based mercury removal adsorbent material through a gas phase in-situ reduction method. The preparation methodis simple, the preparation cost is low, and the prepared in-situ level nano selenium carbon based mercury removal adsorbent material has the advantages of being high in selenium crystal adhesion force, not easy to fall off, and good in dispersity. There are many mercury adsorption active sites and active centers, the mercury adsorption capacity is high, the material has long service life, and therequirements of the mercury related industry, natural-gas mercury removal, a non-ferrous metal smelting plant, a coal-fired power plant and the like for complex mercury-containing flue gas exhaust processing are met.

Sulfur transfer catalyst comprises spinel compound contained with alkaline-earth metal and aluminum, or contained rare earth metal except cerium, or without vanadium; and oxide with adding metal component of cerium oxide and zinc oxide; based on catalyst, the weight share is spinel compound 50-90%, cerium oxide and zinc oxide 10-50%; the average particle diameter of cerium oxide and zinc oxide is less separately 130A and 300A with XRD method. It can decrease the reproduced SOx with high active in FCC and sulfur content in gas outcome.

The invention discloses a preparation method of a roasting-free pre-vulcanized hydrogenation catalyst. The method comprises the steps that the environment-friendly dipping technology is adopted for preparing the hydrogenation catalyst, after the dipped catalyst is treated under the temperature of 180-250 DEG C, an organic solvent, elemental sulfur and auxiliaries are added to be mixed to be uniform, and thermal treatment is performed to obtain the roasting-free pre-vulcanized hydrogenation catalyst. The method solves the problems that a conventional catalyst is low in activity, poor in dispersity, long in vulcanization on-stream time and high in operation cost, and meanwhile overcomes the defects that the vulcanized catalyst preparation process is complex and concentrated heat release is easy. The pre-vulcanized hydrogenation catalyst prepared through the method is high in strength, good in activity and short in preparation process flow and has the good application value.

The invention provides a preparation method of a propylene copolymer with ethylene content lower than 0.5% (wt) and wide molecular weight distribution. The method comprises a catalyst system and a two-step polymerization process. The catalyst system comprises a Ziegler-Natta catalyst with organosilane with extremely high hydrogen sensitivity. With the catalyst system, extremely high molecular weight can be produced in first step polymerization, and extremely low molecular weight can be produced in the second step. Polymerization products obtained in the two steps are mechanically mixed, wherein melt flow rate ratio (2.16kg, 230 DEG C) of the fist step and the second step is higher than 400, such that the propylene copolymer with wide molecular weight distribution can be obtained.

The invention discloses a preparation method of a catalyst with high CO purification performance and the catalyst. The catalyst is used for being coated on the surface of a carrier to prepare an engine tail gas purification catalyst and is prepared by loading noble metal on a carrier material; the noble metal is Ru and one or more of Pt, Pd and Rh, the Ru content is 1g/ft < 3 >-30g/ft < 3 >, and the rest is 5g/ft < 3 >-40g/ft < 3 >; according to the catalyst, a loading material of Ru is adjusted, oxygen deficiency of a Ce-containing material is utilized, the synergistic effect of Ru and the material is increased, migration and sintering of Ru particles under the high-temperature condition are inhibited, and the anti-aging performance of Ru is improved; meanwhile, the roasting temperature of Ru powder is changed, a Ru precursor is firstly converted into Ru oxide, and strong interaction is generated between the Ru oxide and the carrier, so that Ru is in the optimal active valence state, the number of active centers of the whole catalyst coating is increased, and the CO performance and durability of the catalyst are improved; according to the invention, Ru with relatively low price is adopted to replace a part of Pt, Pd and Rh, so that the cost of the catalyst is reduced, and the cost performance of the catalyst is improved.

The invention provides a downer reactor light hydrocarbon catalytic converting method and device. The method specifically includes the following steps of firstly, making a preheated or non-preheated light hydrocarbon raw material and a low-temperature regenerant from a regenerant cooler enter the inlet end of a downer reactor and flow downwards along the reactor for catalytic cracking and other reactions, and making a mixture of reaction oil gas and a catalyst go downwards to the tail end of the reactor to be rapidly separated so that the catalyst and the oil gas can be rapidly separated, wherein the main operation conditions include the reaction temperature of 520-680 DEG C, the reaction pressure of 0.11-0.4 MPa, the contact time of 0.05-2 seconds and the agent-to-oil ratio of 6-50; secondly, making a separated to-be-generated agent enter a regenerator to be burned and regenerated after the to-be-generated agent is subjected to steam stripping through a to-be-generated agent stripper,wherein the regeneration temperature is controlled to be 630-730 DEG C; thirdly, making a regenerant from the regenerator enter the regenerant cooler to be cooled into 200-720 DEG C, and making the regenerant recycled in the downer reactor.