摘要:
A process for dehydrogenating alkane or alkylaromatic compounds comprising contacting the given compound and a dehydrogenation catalyst in a fluidized bed. The dehydrogenation catalyst is prepared from an at least partially deactivated platinum/gallium catalyst on an alumina-based support that is reconstituted by impregnating it with a platinum salt solution, then calcining it at a temperature from 400° C. to 1000° C., under conditions such that it has a platinum content ranging from 1 to 500 ppm, based on weight of catalyst; a gallium content ranging from 0.2 to 2.0 wt %; and a platinum to gallium ratio ranging from 1:20,000 to 1:4. It also has a Pt retention that is equal to or greater than that of a fresh catalyst being used in a same or similar catalytic process.
摘要:
Increase propane dehydrogenation activity of a partially deactivated dehydrogenation catalyst by heating the partially deactivated catalyst to a temperature of at least 660° C., conditioning the heated catalyst in an oxygen-containing atmosphere and, optionally, stripping molecular oxygen from the conditioned catalyst.
摘要:
Increase propane dehydrogenation activity of a partially deactivated dehydrogenation catalyst by heating the partially deactivated catalyst to a temperature of at least 660° C, conditioning the heated catalyst in an oxygen-containing atmosphere and, optionally, stripping molecular oxygen from the conditioned catalyst.
摘要:
A process to prepare propylene showing desirably increased selectivity comprises contacting, at an elevated temperature, ethanol and a rhenium oxide-modified ZSM-5 zeolite catalyst, under conditions suitable to form propylene. The rhenium oxide-modified ZSM-5 zeolite catalyst may be prepared by impregnating, in an aqueous or organic medium, a ZSM-5 zeolite with a rhenium source, under conditions suitable to form a catalyst precursor, and calcining the catalyst precursor under conditions suitable to form a rhenium oxide-modified ZSM-5 zeolite catalyst.
摘要:
Dispersed Active Metal catalyst for hydrogenation reactions is produced by treating a substantially catalytically inactive metal particulate with a solution capable of oxidizing the metal particulate and comprising of at least one compound of a hydrogenation catalyst metal thereby forming a layer of at least one of hydroxides and oxides thereon. The metal particulate is activated by treatment with a hydrogen-containing gas at elevated temperatures to form a porous layer of Dispersed Active Metal catalyst. Preferably, the treated metal particulate is dried prior to activation, and also preferably calcined in an oxidant-containing atmosphere prior to activation. The treatment solution may advantageously contain a compound of at least one promoter metal for the added catalyst metal. The porosity of the layer provides enhanced catalyst activity as well as improved methane selectivity in the Fischer-Tropsch process.
摘要:
A process for converting an oxygenate-containing feedstock to a product comprising olefins comprises including in the oxygenate-containing feedstock an amount of ammonia. The presence of the ammonia increases the product's ratio of ethylene to propylene.
摘要:
A process for enhancing the activity of a catalyst metal particulate for hydrogenation reactions comprising calcining the particulate in an oxidant-containing atmosphere to partially oxidize it thereby forming a porous layer of oxides thereon, treating with an solution capable of oxidizing the calcined metal particulate and comprising a compound of a hydrogenation catalyst metal to where said metal particulate has absorbed a volume of solution equal to at least about 10% of its calculated pore volume and activating it by treatment with a hydrogen-containing gas at elevated temperatures thereby forming a dispersed active metal catalyst. Preferably, the treated particulate is calcined a second time under the same conditions as the first before final activation with a hydrogen-containing gas. The metal particulate is preferably sized after each calcination and any agglomerates larger than 250 microns are comminuted to a desired size.
摘要:
Catalytic composition for production of olefins and methods of using same to decrease production of oxygenate byproducts. The catalytic composition includes an admixture of an alumina dehydration catalyst and at least one additional metal oxide.
摘要:
A process to prepare propylene showing desirably increased selectivity comprises contacting, at an elevated temperature, ethanol and a rhenium oxide-modified ZSM-5 zeolite catalyst, under conditions suitable to form propylene. The rhenium oxide-modified ZSM-5 zeolite catalyst may be prepared by impregnating, in an aqueous or organic medium, a ZSM-5 zeolite with a rhenium source, under conditions suitable to form a catalyst precursor, and calcining the catalyst precursor under conditions suitable to form a rhenium oxide-modified ZSM-5 zeolite catalyst.
摘要:
Catalytic composition for production of olefins and methods of using same to decrease production of oxygenate byproducts. The catalytic composition includes an admixture of an alumina dehydration catalyst and at least one additional metal oxide.