A kind of polyaluminum chloride-chitosan composite flocculant and its preparation method and application

Abstract

The invention belongs to the technical field of flocculant production and specifically relates to an aluminum polychlorid-chitosan composite flocculant, a preparation method and an application thereof. The preparation method for the aluminum polychlorid-chitosan composite flocculant comprises the following steps: grinding and sieving aluminum ash, removing impurities by washing and then mixing with water and concentrated hydrochloric acid, stirring, reacting and curing, thereby acquiring aluminum polychlorid; dropwise adding a chitosan / acetic acid solution into a sodium polyphosphate solution and then regulating the pH of the reaction system to 4-5; firstly reacting while quickly stirring and then reacting while slowly stirring, adding aluminum polychlorid after the reaction is ended, and stirring and reacting for 1-3h at 80-100 DEG C, thereby acquiring the aluminum polychlorid-chitosan composite flocculant. The preparation method is simple in operation, low in cost and suitable for industrial production. The aluminum ash is taken as the raw material for preparing the aluminum polychlorid; the waste is turned into wealth; the production cost is lowered; environmental pollution caused by the solid waste of the aluminum ash is avoided.

Description

technical field [0001] The invention belongs to the technical field of flocculant production, and in particular relates to a polyaluminum chloride-chitosan composite flocculant and its preparation method and application. Background technique [0002] Aluminum ash is produced in the production process of aluminum melting such as electrolysis of primary aluminum, casting aluminum products, aluminum alloy refining, etc. The composition of aluminum ash has obvious differences according to the composition of raw materials and processes, mainly based on Al 2 o 3 , metal aluminum, and a mixture of salt flux, etc. With Al 2 o 3 Contains 20% to 40%, Al contains 10% to 30%, Si, Mg, Fe oxides contain 7% to 15%, K, Na, Ca, Mg chlorides and a small amount of fluoride contain 15% to 30%, Part of the aluminum oxide and aluminum nitride is attached to the surface of the aluminum metal. By the end of 2015, China's output of electrolytic aluminum and alumina accounted for 54.5% and 48.8%...

AI Technical Summary

Problems solved by technology

At present, the processing method of aluminum ash is mainly stockpiling, which not only occupies a large amount of land, but also contains harmful substances (especially fluorine) in aluminum ash, which poses a serious threat to human health and ecological environment safety.