Preparation method of demulsifier for oil fields

Abstract

The invention discloses a preparation method of a demulsifier for oil fields. In the method, fatty alcohol is used as a raw material, and the demulsifier is prepared by crosslinking and modifying after reacting the fatty alcohol with oxirane and epoxypropane. First, the fatty alcohol is used as an initiator, and a polyether demulsifier A is prepared by reacting the fatty alcohol with propylene oxide and ethylene oxide in the presence of a basic catalyst. Then, a product B is prepared by carrying out self-crosslinking reaction on the polyether demulsifier A with polycarboxylic acid under the action of the catalyst. Finally, a final product, i.e. the high-performance demulsifier, is prepared by carrying out self-crosslinking reaction on the polyether demulsifier A and the product B in a solvent with adoption of toluene diisocynate. The demulsifier prepared with the method has the advantages of high relative molecular weight, ideal dewatering effect and good broad spectrum property, and can be used for demulsifying and dewatering oil field crude oil. Separated water is clear, and the use amount of the demulsifier is small.

Description

technical field [0001] The invention relates to a preparation method of a demulsifier, in particular to a preparation method of an oilfield demulsifier used for oil field crude oil collection and transportation dehydration treatment. Background technique [0002] Water is often mixed in the oil extraction process, and the crude oil must be dehydrated before transportation to reduce transportation costs. The free water in crude oil is easy to separate and remove, while the removal of emulsified water in crude oil generally requires the addition of demulsifiers. At present, polyether demulsifiers are mainly used in China. The hydrogen compound is used as an initiator, and under the action of an alkali metal catalyst, it undergoes anionic ring-opening polymerization reaction with an oxyalkylene to prepare a polyoxyethylene polyoxypropylene ether demulsifier. This process has many side reactions when preparing higher molecular weight polyether, the obtained polyether has a rela...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the problems existing in the existing polyether demulsifiers, the object of the present invention is to provide a method for preparing demulsifiers for oilfields. On the basis of preparing polyether demulsifiers, the present invention further prepares polyether demulsifiers The demulsifier uses polycarboxylic acid for esterification and crosslinking reaction, and then reacts the obtained product with toluene diisocyanate and polyether demulsifier