JPWO2022083396A5 - - Google Patents

Claims (6)

It includes a vinyl acetate synthesis process, a vinyl acetate purification process, and a separation process of vinyl acetate and ethyl acetate, and the vinyl acetate synthesis process mainly consists of an ethylene recovery column (117) and an acetic acid evaporator (103) connected in sequence. , an oxygen mixer (106), a vinyl acetate synthesis reactor (107), a first gas separation column (108), a second gas separation column (112) and a circulating gas compressor (101), and the first gas separation The column (108) and the second gas separation column (112) are connected to a degassing can (113), and then connected to a recovery gas compressor (114), a water washing column (115), an absorption column (116), and a desorption column (122). ), and the vinyl acetate purification process mainly consists of an acetic acid tower (201), a crude VAC tower (202), a purified VAC tower (203), and the top of the crude VAC tower (202), which are connected in sequence. an aldehyde ester concentration column (204) and an acetaldehyde column (205) sequentially connected to one branch; an aqueous phase sequentially connected to one branch at the top of the acetic acid column (201) and the crude VAC column (202); It consists of a receiving tank (207) and a dehydration tower (206), and the separation process of vinyl acetate and ethyl acetate is mainly performed by an extraction rectification tower (401), an extraction rectification tower condenser (402), and an extraction rectification tower (402), which are connected in sequence. A distillation column subcooler (403), an extraction rectification column phase separator (404), and an ethyl acetate column (405) to which the extraction rectification column (401) vessel is connected in sequence, an ethyl acetate column condenser (406), and an acetic acid column. A method for producing ethylene acetate comprising an ethyl tower subcooler (407) and an ethyl acetate tower phase separator (408), the separation process of vinyl acetate and ethyl acetate using an extractive rectification method ,
A stream containing acetic acid, vinyl acetate, water and ethyl acetate extracted from the side line of the acetic acid tower (201) enters the middle of the extraction rectification tower (401), and is passed through the extraction rectification tower using acetic acid as an extractant. (401), and the main components in the top vapor of the extraction rectification column (401) are vinyl acetate, water, and a trace amount of ethyl acetate that has not been completely removed. The condensate obtained by condensation in (402) enters the extraction rectification column subcooler (403), and after being further cooled, it is sent to the extraction rectification column phase separator (404) for phase separation. After phase separation, the oil phase portion is refluxed, the remaining portion is extracted and sent to the acetic acid tower (201) of the previous system for treatment, and the aqueous phase is sent to the dehydration tower (206) to form an aqueous phase. A method characterized by recovering organic matter therein . The separation process of vinyl acetate and ethyl acetate uses an extraction rectification method, and the main equipment includes the extraction rectification column (401), the ethyl acetate column (405), and the extraction rectification column condenser (402). , the extraction rectification column subcooler (403), the extraction rectification column phase separator (404), the ethyl acetate column condenser (406), the ethyl acetate column subcooler (407), the acetic acid an ethyl column phase separator (408); Two branches are provided at the oil phase outlet of the extraction rectification column phase separator (404), which are sequentially connected to the distillation column phase separator (404), and are respectively connected to the extraction rectification column (401) and the oil phase outlet of the extraction rectification column phase separator (404). The acetic acid is returned to the acetic acid column (201), and the aqueous phase outlet is connected to the aqueous phase receiving tank (207), and the column kettle of the extraction rectification column (401) is connected to the ethyl acetate column (405). The top of the ethyl column (405) is connected in sequence to the ethyl acetate column condenser (406), the ethyl acetate column subcooler (407) and the ethyl acetate column phase separator (408), and the ethyl acetate column phase separation The aqueous phase outlet of the vessel (408) is connected to the ethyl acetate column (405), the raw material at the oil phase outlet is sent out from the system, and two branches are provided at the column outlet of the ethyl acetate column (405), 2. The method according to claim 1, characterized in that it is connected to an extraction rectification column and the acetic acid column (201) of the pre-system, respectively . The column kettle of the extraction rectification column (401) contains ethyl acetate, a mixture of a small amount of water and acetic acid, which is put into the ethyl acetate column (405) and rectified, and is then collected in the ethyl acetate column (405). The main components of the tower top vapor are ethyl acetate, water, and a trace amount of vinyl acetate, and the condensate obtained by condensing in the ethyl acetate tower condenser (406) is put into the ethyl acetate tower subcooler (407). , after being cooled, it is sent to the ethyl acetate column phase separator (408) to perform phase separation, the aqueous phase after phase separation is refluxed, and the oil phase is discharged from the system as an ethyl acetate impurity stream; The main component of the column of the ethyl acetate column (405) is acetic acid, a portion of which is returned to the extraction rectification column (401) to become an extractant, and the remainder is returned to the acetic acid column (201) of the previous system. 3. The method according to claim 2 , characterized in that the method is prepared by: According to claim 1, in the separation process of vinyl acetate and ethyl acetate by the extractive rectification method, acetic acid is used as an extractant, and the extractant is added from the upper part of the extractive rectification column (401). the method of. 5. The method according to claim 4, wherein the ratio of the mass flow rate of the extractant acetic acid to the mass flow rate of the charge extracted from the side line of the acetic acid column (201) is 0.2 to 2:1. Method. 6. Process according to claim 5 , characterized in that the ratio of the mass flow rate of the extractant acetic acid to the mass flow rate of the charge withdrawn from the side line of the acetic acid column (201) is 1.2:1.