摘要:
Recovery of an alcohol such as ethanol from a crude alcohol product, preferably obtained from the hydrogenation of acetic acid using a low energy process. The crude ethanol product is separated in a column to produce a distillate stream comprising ethyl acetate and a residue stream comprising ethanol, acetic acid, and water. The ethanol product is recovered in a second column as an ethanol side stream.
摘要:
To reduce acetal concentrations when separating ethanol from a crude product in one or more distillation column, at least one of the columns has a stripping section that comprises at least 40 stages to favor hydrolysis of the acetal. The crude product may comprise ethanol, acetaldehyde, water and one or more acetals, such as diethyl acetal. The acetal concentration may be reduced thus reducing the need to separate acetal from the crude product.
摘要:
In one embodiment, the invention is to a process for purifying a crude ethanol product. The process comprises the step of hydrogenating acetic acid in a first reaction zone in the presence of a first catalyst to form the crude ethanol product comprising ethanol, acetaldehyde, acetic acid, water, and acetal. The process further comprises the step of separating at least a portion of the crude ethanol product into a refined ethanol stream and a by-product stream. The refined ethanol stream comprises ethanol and acetaldehyde; and the by-product stream comprises acetic acid and a substantial portion of the water from the crude ethanol product. The process further comprises the step of hydrolyzing in a second reaction zone at least a portion of the acetal.
摘要:
Purifying and/or recovery of ethanol from a crude ethanol product obtained from the hydrogenation of acetic acid. Separation and purification processes of crude ethanol mixture are employed to allow recovery of ethanol and remove impurities. In addition, the process involves returning acetaldehyde separated from the crude ethanol product to the reactor.
摘要:
A method of removing impurities, such as halogens, sulfurs, and corrosion metal impurities, in an ethanol production process. Ion exchange resins may be used to remove these impurities from acetic acid feed streams and recycle streams that comprise unreacted acetic acid.
摘要:
In one embodiment, the invention is to a process for producing ethanol. The process comprises the step of hydrogenating an acetic acid feed stream in a first reactor to form a crude ethanol product. The crude ethanol product may comprise, among other components, ethanol, acetaldehyde, and residual acetic acid. The process further comprises the step of recovering acetaldehyde from the crude ethanol product. The process further comprises the steps of feeding a first portion of the recovered acetaldehyde to the first reactor and reacting the first portion of the recovered acetaldehyde in the first reactor to form additional ethanol. In addition, the inventive process may comprise the steps of feeding a second portion of the recovered acetaldehyde to a second reactor and reacting the second portion of the recovered acetaldehyde in the second reactor to form an additional product.
摘要:
Purification and/or recovery of ethanol from a crude ethanol product obtained from the hydrogenation of acetic acid. Separation and purification processes of a crude ethanol mixture are employed to allow recovery of ethanol and remove impurities. In particular, the process involves one or more sidedraws to regulate C3+ alcohols concentration in the recovered ethanol.
摘要:
In one embodiment, the present invention is to a process for producing a anhydrous ethanol composition comprising hydrogenating acetic acid in the presence of a catalyst to form a crude ethanol product; separating in a first column at least a portion of the crude ethanol product into a first distillate comprising ethanol, water and ethyl acetate, and a first residue comprising acetic acid; separating in a second column at least a portion of the first distillate into a second distillate comprising ethyl acetate and a second residue comprising ethanol and water; separating in a third column at least a portion of the second residue into a third distillate comprising ethanol and residual water and a third residue comprising separated water; and dehydrating at least a portion of the third distillate to form the anhydrous ethanol composition. The anhydrous ethanol composition, as formed, comprises less than 1 wt. % water, based on the total weight of the anhydrous ethanol composition.
摘要:
A process for operating a distillation column to separate an ethanol mixture comprising ethanol and acetic acid where the recovered ethanol comprises less than 700 wppm acetic acid. The operating conditions for the column may vary depending on the fed composition. In particular the process provides energy efficient recovery of ethanol with low concentration acetic acid.
摘要:
An integrated process for producing ethanol, comprising the step of reacting carbon monoxide with at least one reactant in a reactor containing a reaction medium to produce a liquid reaction product comprising acetic acid. The reaction medium comprises water, acetic acid, methyl acetate, a halogen promoter, and a first catalyst. The process further comprises the steps of directly feeding the liquid reaction product from the reactor to a distillation column and withdrawing from it an overhead stream comprising methyl acetate, and/or halogen promoter, a bottoms stream comprising a solution of the first catalyst, and a liquid acetic acid sidestream; and hydrogenating acetic acid of the liquid acetic acid sidestream in the presence of a second catalyst and under conditions effective to form a crude ethanol product comprising ethanol and water. No flashing vessel is used to purify the liquid reaction product. Ethanol is recovered from the crude ethanol product.