摘要:
A layered catalyst contains a core of at least one, and preferably three, molecular sieve components within a shell layer of reduced molecular sieve content. A preferred catalyst consists of a core of a large pore molecular sieve, preferably a dealuminized Y-type zeolite, a shape selective paraffin cracking/isomerization component, preferably HZSM-5, and a shape selective aliphatic aromatization component, preferably gallium ZSM-5, within a shell of an alumina-rich, matrix. The shell can capture metals from the feeds being processed, it can act as a metals sink, and can remove metals form the unit by attrition. The catalyst is preferably prepared by forming the core and then coating or encapsulating the core with a shell having a reduced molecular sieve content. The shell may contain a pillared clay or other very large pore cracking component. The shell may be an attritable coating of an amorphous rare earth oxide, aluminum oxide and aluminum phosphate composite, which traps metals.
摘要:
The present invention discloses a process for increasing the selectivity of the production of isobutylene in an admixture of C.sub.4 olefins, in a process comprising producing isobutylene, with high selectivity, comprising catalytically producing a first composition comprising at least one C.sub.4 olefin selected from the group consisting of 1-butene, cis-2-butene, trans-2-butene, admixtures thereof and 2-methylpropene admixed with at least one of said 1-butene, cis-2-butene, and trans-2-butene, by passing paraffin containing feed, which feed is free of aromatics, and in which the paraffin contains 5 to 20 carbon atoms, in the vapor phase, over a first catalyst composition, wherein the catalyst comprises ZSM-5 or ZSM-12, and increasing the isobutylene content of the first composition by producing a second composition, by contacting the first composition with a second catalyst composition comprising ZSM-23 under conditions in which the second composition is in the vapor phase, while maintaining the total C.sub.4 olefin content of the second composition substantially identical to the total C.sub.4 olefin content of the first composition.
摘要:
A process and apparatus for fluidized catalytic cracking of heavy oils are disclosed. Quenching and cyclone separation are done in the transfer line to the main distillation column. Quenching hot vapor from the reactor, preferably with liquid recycled from the main column, improves yields, prevents coking in the transfer line and permits higher cracking reactor temperatures. Cyclone separation of quench and/or condensed liquid prevents slugging, or two phase flow, in the transfer line. Some rough-cut fractionation can be achieved in the cyclone separator. Steam stripping of cyclone liquid optimizes operation of the main column.
摘要:
A process and apparatus for fluidized bed catalyst regeneration. A mixture of spent catalyst, recycled hot regenerated catalyst and regeneration gas are charged to a riser having an outlet connective with a coke combustor immersed in a fluidized bed of catalyst. The coke combustor outlet is covered by the dense phase fluidized bed. Additional combustion air may be added to the fluidized bed of catalyst covering the coke combustor outlet for additional catalyst regeneration. Indirect heat exchange may heat spent catalyst in the riser and/or the coke combustor.
摘要:
A process is disclosed for the production of tertiary alkyl ethers wherein linear olefins, particularly n-butene, are isomerized in the vapor phase at high temperature in contact with shape selective metallosilicate catalyst to produce iso-olefin vapor, particularly isobutene. The vaporous iso-butene is then etherified with alkanol to provide alkyl tert-alkyl ether such as MTBE. Unreacted iso-olefin and/or linear olefin and product ether are separated by fractionation and unreacted olefin components recycled. Fractionation of the vapor phase etherification product is carried out by using the fresh liquid linear olefin feedstream as a reflux stream to the fractionator.
摘要:
A fluidized catalytic cracking process and apparatus operates with a two stage hot stripper between the reactor and catalyst regenerator. Addition of hot, regenerated catalyst to spent catalyst from the reactor heats the spent catalyst in the first stripping stage, which preferably uses steam stripping gas. The second stage of stripping occurs about a heat removal stab-in heat exchanger tube bundle, which removes heat from the catalyst during the second stage of stripping. Steam or flue gas may be used in the second stripping stage to fluidize catalyst, improve heat transfer and simultaneously strip the catalyst.
摘要:
Isopentene, or isoamylene, conversion to methyl tert-amyl ether can be substantially improved while high conversion of isobutylene to methyl tert-butyl ether can be maintained by carrying out the overall etherification process with alkanol in a staged manner, wherein the first stage is methanol etherification of a C.sub.5 +, or C.sub.5, hydrocarbon feedstream rich in isoamylene and the second stage is etherification to produce MTBE and additional TAME from a C.sub.4 +, or C.sub.4, feedstream. Unreacted methanol and hydrocarbons from the first etherification are uniquely separated by fractionation from the TAME product by using the second stage C.sub.4 + feedstream as a reflux stream to the fractionator and passed to the second etherification zone. Products from the second etherification zone are separated by distillation to produce MTBE, TAME and C.sub.5 +, or C.sub.5, hydrocarbons as a bottom stream.
摘要:
A process is disclosed for the production of high octane alkyl tertiary alkyl ether rich gasoline and gasoline rich in alkylated aromatics. It is disclosed that unreacted C.sub.3 -C.sub.4 hydrocarbon fraction of etherification feedstock plus unreacted alkanol can be separated and employed as alkylating agents in combination with a feedstream containing light aromatics when the alkylation reaction is carried out under conditions of high severity in contact with a high activity shape selective metallosilicate catalyst such as ZSM-5. Under high severity conditions olefin-assisted paraffin conversion also occurs as well as cracking, redistribution and alkylation. Aromatic rich gasoline is a suitable feedstream to the high severity conversion zone to produce a gasoline rich in alkylated aromatics.
摘要:
Process and apparatus for upgrading paraffinic naphtha to high octane fuel by contacting a fresh virgin naphtha feedstock stream medium pore acid cracking catalyst comprising MCM-22 zeolite under low pressure selective cracking conditions effective to produce increased yield of total C4-C5 branched aliphatic hydrocarbhons. The preferred feedstock is straight run naptha containing C7+ alkanes, at least 15 wt % C7+ cycloaliphatic hydrocarbons and less than 20% aromatics, which can be converted with a fluidized bed catalyst in a vertical riser reactor during a short contact period.The isoalkene products of cracking are etherified to provide high octane fuel components.
摘要:
An integrated process is disclosed that substantially reduces the cost of producing MTBE and other alkyl tertalkyl ethers by eliminating a major portion of the equipment and operating costs associated with the downstream processing of the etherification reactor effluent. The integrated process combines the process for the etherification of iso-olefins and methanol, or other alkanols, to produce methyl tertiary alkyl ethers such as MTBE and/or TAME with the catalytic process for converting feedstock such as oxygenates, light olefins and paraffins to higher molecular weight hydrocarbons. Unconverted reactants from the etherification reaction, which may comprise unreacted alkanol and unreacted hydrocarbons or just unreacted hydrocarbons, are separated from the product ethers and passed to the catalytic conversion process reactor for conversion to gasoline boiling range hydrocarbons.