Abstract:
A method for producing a gas comprising at least 80 vol % carbon monoxide from a Fischer-Tropsch off-gas comprises: (1) feeding Fischer-Tropsch off-gas through a column comprising an adsorbent bed at high pressure and discharging effluent; (2) reducing the pressure in the column and the bed slightly; (3) rinsing the column and the adsorbent bed with methane or a mixture of methane and carbon dioxide; (4) reducing the pressure of the column and adsorbent bed to a low pressure; (5) rinsing the column and adsorbent bed with a mixture of hydrogen and nitrogen; (6) pressurizing the column and adsorbent bed to a high pressure using a mixture of hydrogen and nitrogen. The product stream obtained in step (3) comprising at least 80 vol % carbon monoxide can be sent as feed to a Fischer-Tropsch reaction. In an embodiment, a gas comprising at least 80 vol % hydrogen is also produced.
Abstract:
The invention relates to a process for recovering methane from a gas stream comprising methane and ethylene, comprising a sorption step which comprises contacting the gas stream comprising methane and ethylene with a sorption agent which has a lower affinity for methane than for ethylene, resulting in sorption of ethylene and 0 to 90% of the methane by the sorption agent and in a gas stream comprising methane in an amount of 10 to 100% based on the amount of methane in the gas stream that is subjected to the sorption step; and a desorption step which comprises desorbing sorbed ethylene and optionally sorbed methane resulting in a gas stream comprising ethylene and optionally methane.
Abstract:
The invention provides a process for the preparation of an olefinic product, comprising: (a) reacting an oxygenate feedstock, in a reaction zone in the presence of a molecular sieve catalyst, at a temperature from 350 to 1000° C., to produce a reaction effluent stream, comprising at least oxygenate, olefin, water and acidic by-products; (b) cooling the reaction effluent stream by means of an indirect heat exchange to a temperature greater than the dew point temperature of reaction effluent stream; (c) further rapidly cooling the reaction effluent stream to a temperature lower than the dew point temperature of the reaction effluent stream by direct injection of an aqueous liquid into the reaction effluent stream, to form a first quench effluent stream; and (d) separating the first quench effluent stream into a first liquid quench effluent stream and a first gaseous quench effluent stream, comprising the olefinic product.
Abstract:
This invention concerns a method for recovering carbon monoxide and carbon dioxide from Fischer-Tropsch off-gas by feeding Fischer-Tropsch off-gas through a column comprising an adsorbent bed, and discharging effluent, optionally rinsing the column and the adsorbent bed by feeding NG and discharging effluent until at least 60% of the carbon monoxide that was present in the bed is discharged, pressurizing the column and adsorbent bed with NG, rinsing the column and the adsorbent bed by feeding NG until at least 50% of the carbon dioxide present at the commencement of this rinsing step is discharged, rinsing the column and adsorbent bed by feeding a mixture of hydrogen and nitrogen, pressurizing the column and adsorbent bed by feeding a mixture of hydrogen and nitrogen. With this method a feed comprising at least 50 vol % carbon monoxide can be produced. Furthermore, methane and carbon dioxide at a high pressure can be recovered from the Fischer-Tropsch gas. This can be fed to a gasifier or a reformer. In a preferred embodiment a gas comprising at least 80 vol % hydrogen is produced as well.
Abstract:
The invention provides a process for the preparation of an olefinic product comprising ethylene and/or propylene comprising: a) steam cracking a paraffinic feedstock to obtain an effluent comprising olefins; b) converting an oxygenate to obtain a gaseous effluent comprising olefins; c) subjecting both effluents to water removal and compression steps, wherein the effluents are combined before the water removal step, between the water removal and the compression steps or after the compression step to obtain a combined gaseous effluent; d) removing acid gas from the combined gaseous effluent obtained in step c), wherein the combined gaseous effluent is treated with a caustic solution in a caustic tower and a non-aqueous liquid stream comprising one or more aromatic C7+ hydrocarbons is added to the caustic solution to control the formation of red oil, to obtain a treated gaseous effluent; and e) separating the olefinic product from the treated gaseous effluent.
Abstract:
A process preparing an aromatic product comprising xylene, the process comprising: a) cracking a feedstock to obtain a cracker effluent comprising olefins and aromatics; b) converting an oxygenate feedstock in an oxygenate-to-olefins conversion system, comprising a reaction zone in which an oxygenate feedstock is contacted with a catalyst to obtain a conversion effluent comprising benzene, toluene, xylene and olefins; c) combining at least part of the cracker effluent and at least part of the conversion effluent to obtain a combined effluent, the combined effluent comprising aromatics; d) separating at least a portion of the benzene and/or toluene from the combined effluent to form a benzene and/or toluene stream; e) separating the olefins from the combined effluent; f) separating xylene from the combined effluent to form a xylene stream; and g) recycling at least a part of the benzene and/or toluene streams as recycled aromatics to step b).
Abstract:
The present invention provides a process for the production of alcohols, which process comprises the steps of: (a) reacting an oxygenate and/or olefinic feed in a reactor in the presence of a molecular sieve catalyst to form an effluent comprising olefins, comprising propylene; (b) separating the effluent comprising olefins as obtained in step (a) into at least a first olefinic product fraction comprising propylene and a second olefinic product fraction; (c) subjecting at least part of the first olefinic product fraction as obtained in step (b) to a hydroformylation process to form aldehydes; (d) hydrogenating at least part of the aldehydes as obtained in step (c) to form alcohols; (e) separating at least part of the alcohols as obtained in step (d) into at least a first product fraction of alcohols and a second product fraction of alcohols; and (f) recycling at least part of the first or second product fraction of alcohols to step (a).
Abstract:
The present invention relates to a process for the oxidative regeneration of a deactivated catalyst comprising molecular sieve to provide a regenerated molecular sieve catalyst, wherein said deactivated catalyst is from one or both of an oxygenate to olefin process and a olefin cracking process, said regeneration process comprising at least the steps of providing a regeneration gas stream comprising oxidant; treating the regeneration gas stream with a liquid adsorbent stream comprising an ethylene glycol in a contaminant absorption zone to remove at least a part of one or more of any water, any alkali metal ion and any alkaline earth metal ion present in the regeneration gas stream to provide a treated regeneration gas stream comprising oxidant; regenerating a deactivated catalyst comprising molecular sieve with the treated regeneration gas stream to provide a regenerated catalyst comprising regenerated molecular sieve.
Abstract:
An oxygenate to olefins (OTO) process, comprising the steps of: (i) purifying an oxygenate feedstream comprising one or more ionic contaminants by contacting the feedstream with a membrane, resulting in the formation of a retentate and a permeate separated by the membrane, which permeate is a purified oxygenate stream which contains a lower ionic contaminant concentration than the original oxygenate feedstream; (ii) introducing the purified oxygenate stream into an oxygenate to olefins reaction zone; and (iii) contacting the purified oxygenate stream with a molecular sieve catalyst in the oxygenate to olefins reaction zone to form a product stream comprising olefins.
Abstract:
The invention relates to a process for recovering methane from a gas stream comprising methane and ethylene, comprising: a sorption step which comprises contacting the gas stream comprising methane and ethylene with a sorption agent which has a lower affinity for methane than for ethylene, wherein the gas stream comprising methane and ethylene also comprises a compound for which the sorption agent has a lower affinity than for methane and ethylene, resulting in sorption of ethylene and methane by the sorption agent and in a gas stream comprising the compound for which the sorption agent has a lower affinity than for methane and ethylene; a first desorption step which comprises desorbing part of the sorbed methane resulting in a gas stream comprising methane in an amount of 1 to 99.9% based on the amount of methane in the gas stream that is subjected to the sorption step; and a second desorption step which comprises desorbing sorbed compounds resulting in a gas stream comprising the desorbed compounds.