Benzene recovery-HongYe silicone

Benzene recovery        Epoxy resin is made up of two phenol propane and epichlorohydrin in the presence of sodium hydroxide catalysis and made. In the process of reaction to generate salt and water. In order to make the resin and salt layers separated, using benzene as extractant. Resin is dissolved, and salt, water, impurities. Then, benzene resin liquid and water azeotropic distillation. After filtering to trace salt, then often pressure, vacuum evaporation of solvent benzene product.        In production, because of using benzene as extracting agent, every meal is about 4 tons of benzene resin. In the reaction process and post processing, benzene escape is very serious, the amount is amazing. With an annual output of 500 tons of epoxy resin plant, the annual net loss of about 100 tons of benzene. Among them, a part is placed under the foot when the brine away; a part in atmospheric distillation from; a part in vacuum distillation when removed, by the tail gas discharged into the atmosphere. In order to save materials, reduce cost, improve working conditions, reduce environmental pollution, if the vacuum pump exhaust pipe in installation of a condenser tube, the benzene condensation recovery ( condenser cooling surface of large vacuum pump models .). After years of production practice has proved, the recovery of benzene need only often pressure distillation to intercept the distillate, can be used for the production of epoxy resin, but made no impact on product quality. Vacuum pump exhaust tube of a condenser does not affect the normal use of the vacuum pump, vacuum degree will not be reduced. In this way, each producing 1 tons of recyclable 50 kilograms of epoxy resin.