Separation and purification method for pre-hydrogenation of butanol and octanol waste liquid

Abstract

The invention discloses a pre-hydrogenation separation and purification method of a butanol and octanol waste liquid, and belongs to the technical field of butanol and octanol. The method is provided to solve the problem of low utilization rate or short catalyst life in the prior art. The method comprises: removing heavy components from the butanol and octanol waste liquid, carrying out mixing hydrogenation on aldehyde in the waste liquid to form alcohol, and carrying out a rectification process to obtain a highly-pure butanol product and a highly-pure octanol product. The method concretely comprises the steps of heavy component removal, hydrogenation, dewatering, butanol product separation, and extraction of the octanol product from a lateral line. The method greatly improves the utilization rate of the butanol and octanol waste liquid, and increases economic benefits. The method reduces the composition complexity of a material through a hydrogenation process in order to reduce the difficulty of a rectifying unit and reduce the separation cost. Removal of C12 and C16 heavy components from the butanol and octanol waste liquid reduces colloids going through a catalyst bed layer in a reactor, so prolongation of the service life of the catalyst is facilitated, and the stability of a hydrogenation apparatus is improved.

Description

technical field [0001] The invention relates to a method for recovering butanol and octanol from butanol waste liquid, more specifically, the invention relates to a method for obtaining butanol and octanol products through hydrogenation and refining process. Background technique [0002] Butanol and octanol (referred to as butanol) are mainly used in the production of plasticizers dioctyl phthalate (DOP) and dibutyl phthalate (DBP). With the development of my country's plastics industry, the market demand for octyl alcohol is increasing year by year, and the production capacity of octyl alcohol in China is also increasing year by year. There is a small amount of discharge from the evaporator, phase separator and weight removal tower of the reactor of the butanol plant, and the discharged mixed liquid is called the butanol raffinate, which is equivalent to about 10% of the product quality of butanol, and It contains a lot of valuable components, but due to its complex compos...

AI Technical Summary

Problems solved by technology

CN102309968A discloses a liquid-phase hydrogenation catalyst for aldehydes, nickel or its oxide is 8-35%, at least one element in IA or IIA group or its oxide is (0.01-2.0)wt%, IIIA or IV group At least one element or its oxide is (0.01-20.0)wt%, the rare earth element is (0.01-5)wt%, and alumina is the carrier. The catalyst has high activity at low temperature, but the catalyst composition is relatively complex

This method has the problems of many separation equipments, octanol is distilled from the top of the rectification tower twice, and high energy consumption.

[0009] Some of the existing butanol waste liquid hydrogenation technologies have the problem of low utilization rate, some have the problem of high energy consumption, and some have the problem of short catalyst life

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