At present, most research on the application of bentonite in water treatment uses powdered adsorbents to treat wastewater. The powdered adsorbent material has fine particle size and is easy to disperse and powder after encountering water, making subsequent solid-liquid separation very difficult and easy to form new industrial sludge. This secondary sludge formed by the enrichment of heavy metal ions is more harmful to the environment. This project aims at the problem that powdered bentonite or modified bentonite is difficult to separate and recycle from the treatment liquid after being used as an adsorbent in aqueous solution. With bentonite as the main body and acrylamide and acrylic acid as polymerization monomers, a series of composite bentonite adsorbents that deeply remove inorganic heavy metal ions and organic matters in water have been synthesized by aqueous solution and emulsion polymerization methods respectively. The adsorbents have high adsorption performance, low cost, easy regeneration, and are convenient for practical industrial use.

Most adsorbents for wastewater treatment and deep purification of drinking currently use activated carbon. The products of this project have the advantages of low cost and rich raw material sources, and have significant economic benefits. They can replace activated carbon and have broad application prospects. The product cost is 3500 yuan/ton, and the selling price is based on the activated carbon price of 5000 yuan/ton. The annual profit of the composite bentonite adsorbent enterprise with an annual output of 5000 tons: 5000 yuan*(5000-3500)= 7.5 million yuan.

This project is a key science and technology support plan of Tianjin City (project number: 10ZCKFSH01900); 4 authorized invention patents have been obtained.