PREPARATION OF ACRYLIC ACID

• Main Authors: SATOU TAKAHISA, OOKUBO ATSUSHI, HARUNA YOSHINOBU
• Format: Patent
• Language: English
• Published: 08.03.1984
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

PURPOSE:To effect the effective utilization and detoxication of the waste water discharaged from the process of the two-step oxidation of propylene to acrylic acid recycling the waste gas to the second reactor, by concentrating the waste water by a double-effect evaporator, and utilizing the concentrated waste water as a heat source of the second reactor and evaporator. CONSTITUTION:Propylene 2 is catalytically oxidized in vapor phase in two steps comprising the first step 101 and the second step 102, and the produced acrylic acid 8 is collected 103 in the form of an aqueous solution. A part 3 of the produced waste gas 11 is recycled to the first reaction system. Acrylic acid is separated 104-107 from the collected aqueous solution 9 of acrylic acid, and the waste water 23 generated by the process is concentrated with a double- effect evaporator. The steam 6 generated from the first evaporator 109 is used as a heat source of the second reaction, and the steam 27 generated from the second evaporator 110 is used as the heat source of the first evaporator 109, and the steam is recycled and utilized for the collection 10 of acrylic acid. The concentrated waste water 13 discharged from the evaporator 110 is completely oxidized 112 together with the remaining part 12 of the waste gas 11 and cleaned in high efficiency.