Method for preparing cationic cross-linked starch xanthate

Abstract

The invention discloses a method for preparing cationic cross-linked starch xanthate. The method comprises the following steps of: dissolving NaOH and 2,3-epoxypropyltrimethyl ammonium chloride in cold water, and stirring and mixing with starch; reacting for 9 minutes at the temperature of 60 DEG C in a fast microwave reactor; washing products by using an aqueous solution of ethanol, and finally, drying to obtain etherified starch; adding an alkaline solution prepared by water, sodium hydroxide and sodium chloride into etherified starch to be mixed to form slurry; dissolving epoxy chloropropane in the alkaline solution, dripping the mixture into the slurry, and reacting for 2 hours at the temperature of 50 DEG C; regulating the pH value of the solution to be at 7 by using hydrochloric acid; washing by using absolute ethyl alcohol after suction filtration, and drying to obtain the cross-linked etherified starch; dissolving the etherified starch into the water, adding a solution of sodium hydroxide and adding carbon disulfide, stirring to react for 2 hours at the temperature of 50 DEG C, adding a solution of magnesium sulfate, and continuously reacting for 10 minutes; and performing suction filtration, washing by using distilled water, acetone and diethyl ether in sequence, and drying to obtain the cationic cross-linked starch xanthate. When the cationic cross-linked starch xanthate is used for treating heavy metal wastewater, a cationic polymer is not required to be added.

Description

technical field [0001] The invention relates to a preparation method of cationic crosslinked starch xanthate. Background technique [0002] With the rapid development of my country's industry, the discharge of wastewater containing heavy metals has increased, and the pollution problem has become increasingly serious. Generally speaking, heavy metal pollution refers to environmental pollution caused by heavy metals with significant biological toxicity such as lead, mercury, cadmium, chromium, copper, and metalloid arsenic. Heavy metal wastewater mainly comes from mine drainage, waste rock leaching water, ore dressing plant tailings drainage, non-ferrous metal enterprise production wastewater, electroplating wastewater, steel plant pickling drainage, etc. These large amounts of heavy metal-containing wastewater, except for some valuable high-concentration In addition to the waste liquid being recycled by enterprises or professional recycling companies, a large amount of low-c...

AI Technical Summary

Problems solved by technology

There is also research to prepare thioaminostarch xanthate (DSX) or soluble starch-based xanthate-polyacrylamide graft copolymer (SSXA) with starch and acrylamide graft copolymerization, but the preparation process is cumbersome and the cost is relatively high. High, difficult to popularize and apply

[0009] Existing studies have shown that insoluble starch xanthate is not stable, and its aqueous solution is prone to side reactions such as oxidation, hydrolysis and decomposition during storage, resulting in a decrease in sulfur content; at the same time, the use of insoluble starch xanthate to treat wastewater For heavy metals, it is often necessary to add cationic polymers to improve the metal adsorption capacity and overcome the disadvantage of poor stability of insoluble starch xanthate

Cationic starch xanthate can solve the problem of poor stability of insoluble starch xanthate and the need to add cationic polymers in the treatment of industrial heavy metal wastewater