The disclosure relates to iron-doped potassium titanate nanotube catalysts, and methods of making and using such catalysts. The catalysts can be used in the hydrogenation of carbon dioxide (CO.sub.2) for the production of light olefins.

In a process for producing styrene, benzene is alkylated with ethylene to produce ethylbenzene and at least some of the ethylbenzene is dehydrogenated to produce styrene, together with benzene and toluene as by-products. At least part of the benzene by-product is passed through a bed of an adsorbent comprising at least one of an acidic clay, alumina, an acidic ion exchange resin and an acidic molecular sieve to remove basic nitrogenous impurities therefrom and produce a purified benzene by-product, which is then recycled to the alkylation step.

The present invention relates to a catalyst for oxidative dehydrogenation and a method of preparing the same. More particularly, the present invention provides a catalyst for oxidative dehydrogenation having a porous structure which may easily control heat generation due to high-temperature and high-pressure reaction conditions and side reaction due to the porous structure and thus exhibits superior product selectivity, and a method of preparing the catalyst.

A reactor system for dehydrogenation of ethylbenzene to styrene in a given temperature range T upon bringing a reactant stream including ethylbenzene into contact with a catalytic mixture. The reactor system includes a reactor unit arranged to accommodate the catalytic mixture, the catalytic mixture including catalyst particles in intimate contact with a ferromagnetic material, where the catalyst particles are arranged to catalyze the dehydrogenation of ethylbenzene to styrene. The reactor system moreover includes an induction coil arranged to be powered by a power source supplying alternating current and being positioned so as to generate an alternating magnetic field within the reactor unit upon energization by the power source, whereby the catalytic mixture is heated to a temperature within the temperature range T by means of the alternating magnetic field. Also, a catalytic mixture and a method of dehydrogenating ethylbenzene to styrene.

A process for the preparation of an F-T catalyst in which the presence of alkaline earth metals is minimized in the support itself and in the processing conditions, in order to provide a catalyst with an alkaline earth metal content of less than 2000 ppm.

A multi-stage dehydrogenation process including contacting, in a first stage, a feed stream comprising a hydrocarbon and steam with a dehydrogenation catalyst under dehydrogenation conditions to yield a first stage effluent, heating the first stage effluent, and contacting, in a second stage, the heated first stage effluent with a dehydrogenation catalyst under dehydrogenation conditions to yield a second stage effluent comprising a dehydrogenation product, wherein the first stage includes a first reactor and a second reactor arranged in parallel, and wherein the second stage includes a third reactor connected in series with the first reactor and the second reactor. A multi-stage dehydrogenation system for carrying out dehydrogenation is also provided.

A process of methane catalytic conversion produces olefins, aromatics, and hydrogen under oxygen-free, continuous flowing conditions. Such a process has little coke deposition and realizes atom-economic conversion. Under the conditions encountered in a fixed bed reactor (i.e. reaction temperature: 750-1200 C.; reaction pressure: atmospheric pressure; the weight hourly space velocity of feed gas: 1000-30000 ml/g/h; and fixed bed), conversion of methane is 8-50%. The selectivity of olefins is 30-90%. And selectivity of aromatics is 10-70%. The catalyst for this methane conversion has a SiO.sub.2-based matrix having active species that are formed by confining dopant metal atoms in the lattice of the matrix.

One aspect of the present invention provides a method for preparing a ferrite metal oxide catalyst, comprising (a) preparing a precursor solution by dissolving a magnesium nitrate precursor and an iron nitrate precursor in a polar solvent, (b) forming a catalyst powder by spray-pyrolyzing the precursor solution into a reactor using a carrier gas, and (c) calcinating the catalyst powder in a reservoir after conveying the catalyst powder to the reservoir. The method may increase the activity and stability of a catalyst powder by additionally performing a step of calcinating the catalyst powder at a certain temperature for a certain period of time, and may increase the purity of the catalyst by reducing moisture and nitrate remaining in the catalyst. Also, when using the catalyst in an oxidative dehydrogenation of n-butene, the selectivity and purity of 1,3-butadiene may increase.

Provided is a method for the preparation of a metal lattice-doping catalyst in an amorphous molten state, and the process of catalyzing methane to make olefins, aromatics, and hydrogen using the catalyst under oxygen-free, continuous flowing conditions. Such a process has little coke deposition and realizes atom-economic conversion. Under the conditions encountered in a fixed bed reactor (i.e. reaction temperature: 7501200 C.; reaction pressure: atmospheric pressure; the weight hourly space velocity of feed gas: 100030000 ml/g/h; and fixed bed), conversion of methane is 8-50%. The selectivity of olefins is 3090%. And selectivity of aromatics is 1070%. There is no coking. The reaction process has many advantages, including a long catalyst life (>100 hrs), high stability of redox and hydrothermal properties under high temperature, high selectivity towards target products, zero coke deposition, easy separation of products, good reproducibility, safe and reliable operation, etc., all of which are very desirable for industrial application.

The present invention provides a process for producing butadiene by oxidative dehydrogenation of butylene, comprising: a reaction stage, wherein a multi-stage adiabatic fixed bed in series is used, wherein butylene, oxygen-comprising gas and water are reacted in the presence of a catalyst in each stage of the adiabatic fixed bed with the first stage of the adiabatic fixed bed being further separately fed a diluent, being nitrogen and/or carbon dioxide, and the molar ratio between this separately fed diluents and the oxygen of all the oxygen-comprising gases fed in the subsequent stage(s) of the adiabatic fixed bed being controlled, wherein the oxygen-comprising gas is air, oxygen-enriched air or oxygen, and at least one of all the oxygen-comprising gases fed in the subsequent stage(s) of the adiabatic fixed bed is oxygen-enriched air having a specific oxygen concentration or oxygen; and a post treatment stage, wherein the effluent from the last stage of the adiabatic fixed bed is treated to obtain a product butadiene. The present invention has an advantage that the whole process is with reduced total energy consumption.