摘要:
A process for dehydration of an ethanol feedstock into ethylene, comprising the vaporization of said dilute hydrated ethanol feedstock in an exchanger, with heat exchange with the effluent that is obtained from a last reactor, with said mixture being introduced into said vaporization stage at a pressure that is lower than the pressure of the effluent that is obtained from the last reactor, the compression of the mixture that is vaporized in a compressor, the introduction of the vaporized and compressed mixture, into at least one adiabatic reactor that contains at least one dehydration catalyst.
摘要:
The present invention is a process for dehydrating an alcohol to prepare corresponding olefin(s), comprising: (a) providing a feed (A) comprising at least an alcohol having at least 2 carbon atoms, and preferably at most 5 carbon atoms, or a mixture thereof optionally water, optionally an inert component, in a dehydration unit, (b) placing the feed (A) into contact with an acidic catalyst in a reaction zone of said dehydration unit at conditions effective to dehydrate at least a portion of the alcohol to make an olefin or a mixture of olefins having the same number of carbon atoms as the alcohol, (c) recovering from said dehydration unit an effluent (B) comprising: an olefin or a mixture of olefins, water, undesired by-products including aldehydes and lighter products resulting from degradation of said aldehydes under the conditions of step (b), optionally unconverted alcohol(s) if any, optionally the inert component, wherein, said feed (A)-providing step (a) comprises adding an effective amount of one or more organic compound capable to reduce the undesired by-products by comparison with a non introduction of such compound, said organic compound being chosen among organic acids.
摘要:
The present invention is a process for dehydrating an alcohol to prepare corresponding olefin(s), comprising: (a) providing a feed (A) comprising at least an alcohol having at least 2 carbon atoms, and preferably at most 5 carbon atoms, or a mixture thereof optionally water, optionally an inert component, in a dehydration unit, (b) placing the feed (A) into contact with an acidic catalyst in a reaction zone of said dehydration unit at conditions effective to dehydrate at least a portion of the alcohol to make an olefin or a mixture of olefins having the same number of carbon atoms as the alcohol, (c) recovering from said dehydration unit an effluent (B) comprising : an olefin or a mixture of olefins, water, undesired by-products including aldehydes and lighter products resulting from degradation of said aldehydes under the conditions of step (b), optionally unconverted alcohol(s) if any, optionally the inert component, wherein, said feed (A)-providing step (a) comprises adding an effective amount of one or more organic compound capable to reduce the undesired by-products by comparison with a non introduction of such compound, said organic compound being chosen among organic acids.
摘要:
Process for the production of ethylene from an ethanol feedstock that comprises these stages: a) dehydration to produce at least ethylene and water effluents, b) partial condensation of said ethylene effluent, c) separating phases of said partially condensed ethylene effluent to produce gas and liquid effluents, d) compression of said gas effluent to produce compressed gas effluent, e) washing said compressed gas effluent by contact with the recycled washing water of stage h) to produce washed gas and waste water effluents, f) absorption of said washed gas effluent by contact with at least an absorbent solution to produce purified gas effluent, g) distilling said waste water effluent and, jointly, said water effluent from said dehydration stage to produce at least gas distillate, liquid distillate, purified water effluent, and distillation residue, h) recycling, as washing water, at least a portion of said purified water effluent upstream from the washing stage e).
摘要:
The present invention is a process for dehydrating an alcohol to prepare a corresponding olefin, comprising: (a) providing a composition (A) comprising at least an alcohol having at least 2 carbon atoms, optionally water, optionally an inert component, in a dehydration unit, (b) placing the composition (A) into contact with an acidic catalyst in a reaction zone of said dehydration unit at conditions effective to dehydrate at least a portion of the alcohol to make a corresponding olefin, (c) recovering from said dehydration unit an effluent (B) comprising: at least an olefin, water, undesired by-products including aldehydes and light products, optionally unconverted alcohol(s), optionally the inert component, wherein, said composition (A)—providing step (a) comprises adding an effective amount of one or more sulfur containing compound capable to reduce the undesired by-products by comparison with a non introduction of such sulfur containing compound. The component introduced at step (a) can be chosen from the group consisting of thiols, sulfides, disulfides.
摘要:
The invention relates to a process for dehydration of an ethanol feedstock into ethylene comprising at least the stages: a) A stage for pretreatment of the ethanol feedstock on an acidic solid, b) A stage for evaporation of said pretreated ethanol feedstock in a heat exchanger, c) A stage for superheating said evaporated feedstock in such a way as to bring it to an inlet temperature that is compatible with the temperature of a dehydration reaction, d) A stage for dehydration of said feedstock that is obtained from stage c) in at least one adiabatic reactor that contains at least one dehydration catalyst.
摘要:
The present invention is a process for dehydrating an alcohol to prepare a corresponding olefin, comprising: (a) providing a composition (A) comprising at least an alcohol having at least 2 carbon atoms, optionally water, optionally an inert component, in a dehydration unit, (b) placing the composition (A) into contact with an acidic catalyst in a reaction zone of said dehydration unit at conditions effective to dehydrate at least a portion of the alcohol to make a corresponding olefin, (c) recovering from said dehydration unit an effluent (B) comprising : at least an olefin, water, undesired by-products including aldehydes and light products, optionally unconverted alcohol(s), optionally the inert component, wherein, said composition (A)-providing step (a) comprises adding an effective amount of one or more sulfur containing compound capable to reduce the undesired by-products by comparison with a non introduction of such sulfur containing compound. The component introduced at step (a) can be chosen from the group consisting of thiols, sulfides, disulfides.
摘要:
The invention relates to a process for dehydration of an ethanol feedstock into ethylene comprising at least the stages: a) A stage for pretreatment of the ethanol feedstock on an acidic solid, b) A stage for evaporation of said pretreated ethanol feedstock in a heat exchanger, c) A stage for superheating said evaporated feedstock in such a way as to bring it to an inlet temperature that is compatible with the temperature of a dehydration reaction, d) A stage for dehydration of said feedstock that is obtained from stage c) in at least one adiabatic reactor that contains at least one dehydration catalyst.
摘要:
A process for dehydration of an ethanol feedstock to ethylene by: a) preheating ethanol feedstock by heat exchange with effluent from e), b) pretreating the ethanol feedstock to produce pretreated ethanol feedstock, c) vaporizing a vaporization feedstock containing pretreated ethanol feedstock and at least a portion of the flow of treated water recycled in an exchanger to produce a vaporized feedstock, d) compressing said vaporized feedstock to produce a compressed feedstock, e) dehydrating said compressed feedstock in at least one adiabatic reactor, f) separating the effluent from the last adiabatic reactor of e) into an effluent containing ethylene and an effluent containing water, g) purifying at least a portion of the effluent containing water from 0 and separating at least one flow of treated water and at least one flow of unconverted ethanol, h) recycling at least a portion of the flow of treated water from g) upstream of c).
摘要:
A process for the dehydration of an alcohol having at least 2 carbon atoms to make a corresponding olefin may include introducing in a reactor a stream (A) containing the alcohol, optionally water, and optionally an inert component. The stream (A) may be contacted with a catalyst in the reactor at conditions effective to dehydrate at least a portion of the alcohol to make the corresponding olefin. The process includes recovering from the reactor an olefin containing stream (B). The catalyst may be a crystalline silicate, dealuminated crystalline silicate, or phosphorus modified crystalline silicate, each of the group FER, MWW, EUO, MFS, ZSM-48, MTT or TON having Si/Al ranging from 25 to 90. The weight hourly space velocity (WHSV) of the alcohol may be at least 4 h−1. The temperature may range from 280° C. to 600° C., or from 320° C. to 600° C.