A kind of preparation method of aluminum oxide flocculant inverse microemulsion

Abstract

The invention provides a method for preparing an alumina flocculant inverse microemulsion and the alumina flocculant inverse microemulsion prepared by the method. A stable sodium acrylate-acrylamide inverse microemulsion was prepared by adding a self-made graft emulsifier and other emulsifiers. During the polymerization process, the self-made grafted emulsifier added has a branched chain structure at the lipophilic end, which stabilizes the encapsulation of micelles and droplets, and at the same time slows down the polymerization rate, thereby increasing the molecular weight of the product. The inverse microemulsion obtained by polymerization with low oil-water ratio and high solid content has a long stable storage period.

Description

technical field [0001] The invention relates to a preparation method of a low-oil-water ratio and high solid content inverse microemulsion, in particular to a preparation method of a stable inverse microemulsion and a sodium acrylate-acrylamide flocculant inverse microemulsion. Background technique [0002] The sedimentation and washing of red mud is an important process in alumina production, and the normal operation of this process has a great impact on alumina production and cost reduction. At present, adding flocculant is a common method for separation of red mud in this process. There are two types of flocculants for red mud separation, powder and emulsion. The powder has the disadvantages of long dissolution time and uneven dissolution during use, while the emulsion formulation is divided into two types: inverse emulsion and inverse microemulsion. Inverse microemulsion phase Compared with inverse emulsion products, it has the advantages of good stability, high relativ...

AI Technical Summary

Problems solved by technology

[0003] There are following deficiencies in the technology of preparing sodium acrylate-acrylamide by reverse phase microemulsion at present: (1) the solid content of reverse phase microemulsion is difficult to improve

A large amount of heat will be generated during the polymerization process, the viscosity of the reaction system will gradually increase with the reaction, and it is difficult to release the heat as soon as possible, and the increase in solid content will aggravate this phenomenon, making the inverse microemulsion system unstable and causing production accidents

(2) Inverse microemulsion with low oil-water ratio is difficult to stabilize

[0004] There have been many reports to the inverse microemulsion of preparation stable, high solid content both at home and abroad: (1) Zhang Yuxi etc. 40-45), introduced a system with white oil / span-80+tween-60 / (acrylamide+sodium acrylate) aqueous solution, the inverse microemulsion system is stable, with (NH 4 ) 2 S 2 o 8 / SO 2 Initiation, the molecular weight of the obtained product is 4*10 6 -7.64*10 6 , the average particle size of the polymer in the microemulsion is 60nm, but the monomer content is only 20% in the obtained inverse microemulsion, and no monomer conversion rate has been reported.

(2) Irune Inchausi et al. (see "Macromol.Chem.Phys.", "Synthesis and characterization of polyacrylamides ininverse-emulsions with an isoparaffinic solvent", 2001, 202, 1837_1843), introduced a method based on span-80 / Mentor 28 / AM water solution system, oil-water ratio 0.43:1, (NH 4 ) 2 S 2 o 8 / NaHSO 3 Initiate polymerization at 25°C, the obtained molecular weight exceeds 10 million, but the theoretical solid content is 25%, and the monomer conversion rate is only 70%-95%

[0005] According to reports, the existing sodium acrylate-acrylamide inverse microemulsion polymerization technology cannot achieve the purpose of stable polymerization under the conditions of maintaining high solid content and low oil-water ratio, so that stable microemulsion products cannot be obtained

Images