摘要:
The patent application discloses an integrated process for reformate upgrading. Such a process enables production of a high value product slate, by incorporating the step of reforming along with reaction/diffusion with a zeolite.
摘要:
A process for producing terephthalic acid and/or dimethyl terephthalate includes contacting a toluene-containing reaction stream with a first catalyst under toluene disproportionation conditions to produce an intermediate product stream of para-xylene with negligible ortho-xylene. The first catalyst includes a crystalline molecular sieve which has an ortho-xylene diffusion rate of at least 50 minutes. The first catalyst can be modified by selectivation with a silicon compound or carbon compound. The intermediate product stream, without need for para-xylene purification, is oxidized to terephthalic acid or dimethyl terephthalate.
摘要:
A mixture of aromatic hydrocarbons, comprising ethylbenzene and at least one xylene, is isomerized using a two reactor system to convert the ethylbenzene to compounds that may be removed from the aromatic hydrocarbon stream and to produce a product stream wherein the para-xylene concentration is approximately equal to the equilibrium ratio of the para-isomer. The catalyst present in the first reactor is one that is effective for ethylbenzene conversion with minimal xylene loss when operated under suitable conversion conditions, e.g., a catalyst comprising silica bound ZSM-5 that has been selectivated by one or more silicon impregnations or that has been coke selectivated. The catalyst present in the second reactor is one which is effective to catalyze xylene isomerization when operated under suitable conditions. Each of the catalysts of this invention may contain one or more hydrogenation or dehydrogenation components.
摘要:
There is provided a process for the alkylation of toluene with ethylene to selectively produce para-ethyltoluene over a catalyst which has been selectivated by multiple treatments with a siliceous material.
摘要:
A mixture of aromatic hydrocarbons, comprising ethylbenzene and at least one xylene, is treated to convert the ethylbenzene to compounds that may be removed from the aromatic hydrocarbon stream and to isomerize any xylenes present. The ethylbenzene conversion catalyst is one that is effective for ethylbenzene conversion with minimal xylene loss, e.g., a silica bound intermediate pore size zeolite that has been selectivated. The xylene isomerization catalyst is one which is effective to catalyze xylene isomerization. Each of the catalysts of this invention may contain one or more hydrogenation or dehydrogenation components.
摘要:
There is provided a process for shape selective toluene disproportionation that involves contacting a feedstream which includes toluene under conversion conditions, with ZSM-5 that has been selectivated at least once with an organosilicon selectivating agent. The conversion conditions of the hydrocarbon conversion process provide a toluene conversion of at least 40 wt. %.
摘要:
There is provided a continuous toluene disproportionation process to selectively produce para-xylene. The process includes a steady-state of operation, wherein the conversion of toluene and selectivity to para-xylene is maintained at essentially constant target levels. Prior to such a steady-state of operation, the reaction is conducted under a relatively high temperature.
摘要:
There is provided a process for the net catalytic oxidative dehydrogenation of alkanes to produce alkenes. The process involves simultaneous equilibrium dehydrogenation of alkanes to alkenes and combustion of the hydrogen formed to drive the equilibrium dehydrogenation reaction further to the product alkenes. In the present reaction, the alkane feed is dehydrogenated over an equilbrium dehydrogenation catalyst in a first reactor, and the effluent from the first reactor, along with oxygen, is then passed into a second reactor containing a metal oxide catalyst which serves to selectively catalyze the combustion of hydrogen. This particular mode of operation is termed a separate reactor, cofed oxygen mode. The equilibrium dehydrogenation catalyst may comprise platinum and the selective metal oxide combustion catalyst may contain bismuth, antimony, indium, molybdenum, or a mixture thereof.
摘要:
A process is disclosed for removing sulfur from tail-gas emitted from a Claus sulfur recovery process. First, the tail-gas is oxidized so as to convert sulfur therein to sulfur oxides. Oxidized tail-gas is directed into an absorber where a solid absorbent absorbs substantially all the sulfur oxides thereon. After allowing sufficient time for a desired amount of sulfur oxides to be absorbed, absorption is ceased. Next, the solid absorbent containing the absorbed sulfur oxides is contacted with a reducing gas so as to release an off gas containing hydrogen sulfide and sulfur dioxide. Upon releasing sulfur from the solid absorbent, the solid absorbent is regenerated and redirected into the absorber. Sulfur in the off gas emitted by regeneration is concentrated to an extent sufficient for use within a Claus sulfur recovery process for conversion to elemental sulfur. By combining this process with a Claus sulfur recovery process, sulfur dioxide emissions can be reduced to less than about two parts per million.
摘要:
This invention relates to low sulfur marine/bunker fuel compositions and methods of making same. Contrary to conventional marine/bunker fuel compositions/methods, the inventive lower sulfur compositions/methods focus on use of mostly uncracked components, such as (cat feed) hydrotreated gasoils, and/or can also have reduced contents of residual components.