摘要:
The xylene isomerization process unit and the transalkylation process units are combined in the present invention. A fractionation column can be shared by the two units, reducing the capital cost of the complex. In some embodiments, a split shell fractionation column and a split separator can be used.
摘要:
A synthetic porous cystalline material has the structure of ZSM-5 and a composition involving the molar relationship: X2O3:(n)YO2, wherein X is a trivalent element; Y is a tetravalent element; and n is less than 25, and wherein the slope of the nitrogen sorption isotherm of the material at a partial pressure of nitrogen of 0,4 to 0,7 and a temperature 77 °K is greater than 30. The material has a mesoporous surface area (MSA) greater than 45 m2/g and is useful as a catalyst in the liquid phase isomerization of xylene.
摘要:
Recent experimental work with currently available adsorbents indicates that operating the adsorption section at lower temperatures improves the para-xylene productivity. As a result, an aromatics complex and heat recovery network for a low temperature adsorptive separation-isomerization loop is disclosed resulting in adsorbents savings in combination with higher capacity thereby enabling smaller adsorbents chambers, a smaller total heat exchanger area and a lower heat exchanger shell count.
摘要:
There is provided a combination process for ring opening of aromatics and cycloaliphatics, as well as isomerization of aliphatics using a feedstream comprising hydrocarbons having 6 carbon atoms and at least two reactors connected in series. The first reactor (20) employs a zeolite catalyst and is operated under conditions which particularly promote ring opening. The catalyst in this first reactor may comprise zeolite Beta and platinum. A downstream reactor (40) is operated under conditions to promote isomerization of aliphatics. The catalyst in the second reactor may comprise alumina, platinum and a chloride component. Hydrogen in the effluent of the first reactor (20) may be removed and recycled to the first reactor. Hydrogen required for the second reactor may be satisfied by hydrogen remaining dissolved in the effluent from the first reactor after hydrogen is recycled to the first reactor.
摘要:
Procédé combiné de décyclisation de composés aromatiques et cycloaliphatiques et d'isomérisation de composés aliphatiques, selon lequel on utilise un courant d'alimentation comprenant des hydrocarbures ayant 6 atomes de carbone et au moins deux réacteurs montés en série. Le premier réacteur (20) utilise un catalyseur zéolitique et fonctionne dans des conditions qui stimulent particulièrement la décyclisation. Le catalyseur se trouvant dans ce premier réacteur peut comprendre de la zéolite Beta et du platine. Un réacteur (40) monté en aval fonctionne dans des conditions stimulant l'isomérisation de composés aliphatiques. Le catalyseur se trouvant dans le second réacteur peut comprendre de l'alumine, du platine et un chlorure. L'hydrogène contenu dans l'effluent du premier réacteur (20) peut être enlevé et renvoyé au premier réacteur. L'hydrogène restant dissous dans l'effluent émanant du premier réacteur après que l'hydrogène a été renvoyé au premier réacteur suffit pour alimenter le second réacteur.
摘要:
Processes for the energy efficient recycle of naphthenes in a paraxylene manufacturing process comprise partially condensing a reactor effluent and using a sidedraw tower apparatus. The naphthenes are efficiently separated into the sidedraw stream of the sidedraw tower apparatus. At least a portion of the sidedraw stream is directed to a paraxylene recovery section that produces a paraxylene product and a paraxylene lean stream comprising essentially all of the naphthenes in the sidedraw stream directed to the paraxylene recovery section. The paraxylene lean stream is recycled back to the reactor thereby preventing excessive loss of naphthenes from the processes.
摘要:
There is provided a process for producing adamantane and analogues thereof, namely a hydrocarbon having an adamantane structure which process comprises isomerizing a tricyclic saturated hydrocarbon having ten or more carbon atoms in the presence of a catalyst in which one or two or more metals selected from among the metals belonging to group VIII in the Periodic Table (group 8 to 10 in the new Periodic Table) are supported on zeolite by means of an ion exchange method. It is made possible by the above process to efficiently produce adamantane and analogues thereof in the presence of a solid catalyst without the use of hydrogen chloride.
摘要:
A process is described for increasing the efficiency of para-xylene production using a two stage isomerization sequence. In the first stage of the process, a C9+ aromatics feedstock is subjected to ethylbenzene conversion and xylene isomerization. Non-C¿8? aromatics are removed from the effluent, which is then processed in a second stage of the process to remove para-xylene and isomerize the para-xylene depleted effluent. The effluent from the second stage isomerization unit is then recycled into the inlet of the second stage of the process and a slip stream from the para-xylene separator is recycled to the feedstock and to the effluent of the ethylbenzene conversion unit. In this way, the production of para-xylene is maximized. In a preferred embodiment, toluene is co-fed into the feedstock to minimize the loss of xylenes during the ethylbenzene conversion reaction.