The invention removes oxygenate from an olefin rich gas stream, the process comprising: (a) reacting an oxygenate, in a reaction zone in the presence of a molecular sieve catalyst, at a temperature from 350 to 1000° C., to produce an effluent stream, comprising at least oxygenate, olefin, water and acidic by-products; (b) cooling the effluent stream and contacting it with a first aqueous stream in a quench zone to produce an aqueous stream and an olefin rich gas stream; (c) compressing the olefin rich gas stream in one or more compressors in series to produce a compressed gas stream, (d) cooling the compressed gas stream and separating condensed material from said gas stream after each of the one or more compressors.

The invention removes oxygenate from an olefin rich gas stream, the process comprising: (a) reacting an oxygenate, in a reaction zone in the presence of a molecular sieve catalyst, at a temperature from 350 to 1000° C., to produce an effluent stream, comprising at least oxygenate, olefin, water and acidic by-products; (b) cooling the effluent stream and contacting it with a first aqueous stream in a quench zone to produce an aqueous stream and an olefin rich gas stream; (c) compressing the olefin rich gas stream in one or more compressors in series to produce a compressed gas stream, (d) cooling the compressed gas stream and separating condensed material from said gas stream after each of the one or more compressors.

A process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream comprising n-butenes; B) feeding the input gas stream comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream; Ca) cooling the product gas stream by contacting with a circulating cooling medium in at least one cooling zone; Cb) compressing the cooled product gas stream in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbons in an absorbent, giving an absorbent stream laden with C.sub.4 hydrocarbons and the gas stream d2, and then desorbing the C.sub.4 hydrocarbons from the laden absorbent stream, giving a C.sub.4 product gas stream d1; E) separating the C.sub.4 product stream d1 by extractive distillation; F) distilling the stream e1 into a stream f1 consisting essentially of the selective solvent and a stream f2 comprising butadiene; G) removing a portion of the aqueous phase of the cooling medium which circulates in step Ca) as aqueous purge stream g; H) distillatively separating the aqueous purge stream g into a fraction h1 and a fraction h2 depleted of organic constituents.

A process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream comprising n-butenes; B) feeding the input gas stream comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream; Ca) cooling the product gas stream by contacting with a circulating cooling medium in at least one cooling zone; Cb) compressing the cooled product gas stream in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbons in an absorbent, giving an absorbent stream laden with C.sub.4 hydrocarbons and the gas stream d2, and then desorbing the C.sub.4 hydrocarbons from the laden absorbent stream, giving a C.sub.4 product gas stream d1; E) separating the C.sub.4 product stream d1 by extractive distillation; F) distilling the stream e1 into a stream f1 consisting essentially of the selective solvent and a stream f2 comprising butadiene; G) removing a portion of the aqueous phase of the cooling medium which circulates in step Ca) as aqueous purge stream g; H) distillatively separating the aqueous purge stream g into a fraction h1 and a fraction h2 depleted of organic constituents.

A process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream comprising n-butenes; B) feeding the input gas stream comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream; Ca) cooling the product gas stream by contacting with a circulating cooling medium in at least one cooling zone; Cb) compressing the cooled product gas stream in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons as gas stream d2 from the gas stream c2 by absorbing the C.sub.4 hydrocarbons in an absorbent, giving an absorbent stream laden with C.sub.4 hydrocarbons and the gas stream d2, and then desorbing the C.sub.4 hydrocarbons from the laden absorbent stream, giving a C.sub.4 product gas stream d1; E) separating the C.sub.4 product stream d1 by extractive distillation; F) distilling the stream e1 into a stream f1 consisting essentially of the selective solvent and a stream f2 comprising butadiene; G) removing a portion of the aqueous phase of the cooling medium which circulates in step Ca) as aqueous purge stream g; H) distillatively separating the aqueous purge stream g into a fraction h1 and a fraction h2 depleted of organic constituents.

The present disclosure relates to a material preferably used in a guard bed, and having an increased capacity to adsorb catalyst poisons, as measured by collidine update at 200° C. The material is made by a method in which it is treated by being dried with a drying gas, preferably, at a temperature greater than about 200° C. The treated material may be used to remove impurities from untreated feed streams to, for example, aromatic alkylation and transalkylation processes, where such impurities act as catalyst poisons that cause deactivation of the acidic molecular sieve-based catalysts used, thereby increasing the cycle length of such catalysts.

The present disclosure relates to a material preferably used in a guard bed, and having an increased capacity to adsorb catalyst poisons, as measured by collidine update at 200° C. The material is made by a method in which it is treated by being dried with a drying gas, preferably, at a temperature greater than about 200° C. The treated material may be used to remove impurities from untreated feed streams to, for example, aromatic alkylation and transalkylation processes, where such impurities act as catalyst poisons that cause deactivation of the acidic molecular sieve-based catalysts used, thereby increasing the cycle length of such catalysts.

Disclosed herein is a system for recovering olefins from a vent stream comprising an absorber; and a stripper; where the absorber and the stripper are in a recycle loop; and where the absorber is operative to treat a vent stream with a solvent to remove more than 99 wt % of a halogenated by-product contained in the vent stream and to recover 90 to 95 wt % of olefin molecules present in the vent stream; and where the stripper is operative to remove more than 99 wt % of the halogenated by-products present in the solvent; and where the solvent is recycled to the absorber.

Disclosed herein is a system for recovering olefins from a vent stream comprising an absorber; and a stripper; where the absorber and the stripper are in a recycle loop; and where the absorber is operative to treat a vent stream with a solvent to remove more than 99 wt % of a halogenated by-product contained in the vent stream and to recover 90 to 95 wt % of olefin molecules present in the vent stream; and where the stripper is operative to remove more than 99 wt % of the halogenated by-products present in the solvent; and where the solvent is recycled to the absorber.

Disclosed herein is a system for recovering olefins from a vent stream comprising an absorber; and a stripper; where the absorber and the stripper are in a recycle loop; and where the absorber is operative to treat a vent stream with a solvent to remove more than 99 wt % of a halogenated by-product contained in the vent stream and to recover 90 to 95 wt % of olefin molecules present in the vent stream; and where the stripper is operative to remove more than 99 wt % of the halogenated by-products present in the solvent; and where the solvent is recycled to the absorber.