Study On Preparing Polymeric Aluminum Ferric Chloride And Its Application

In this paper, a new raw material-calcium aluminate are used to prepare the polymeric aluminum ferric chloride by reacting with hydrochloric acid and adding Fe3+ in the reacting system. The optimum preparing factors, which are as follows: mixing 6g raw material with 17ml hydrochloric acid at the ratio of 1:1, adding 380mg FeCl3.6H2O in the reacting system, the reacting temperature being about 100 C and the reacting time being 2 hours, are determined. The result of the flocculation stirring tests show that the polymeric aluminum ferric chloride has a best flocculent effect at the basicity of 75% and the value of pH 7-9.The optimum reaction conditions of synthesizing the cationic polyacrylamide in water solution through Mannich reaction and the influencing factors of cationic degree are discussed. Experimental results show that on the condition of compounding ratio of acrylamide:formaldehyde:dimethylamine=l:0.4:0.48(mol), adding the mixture of formaldehyde and dimethylamine into the polyacrylamide solution in one step, the concentration of polyacrylamide solution being 4%, the reacting temperatures being 55C and the reacting time being 3 hours, the cationic polyacrylamide of 30% cationic degree will be made. It has best flocculent effect at the value of pH 5.The inorganic-organic composite flocculant has been obtained with compounding polymeric aluminum ferric chloride and cationic polyacrylamide in water solution. The flocculent effect of it has been studied with flocculation stirring tests. Results show that the composite flocculant has best effect at the value of pH 8.Results also show that the ratio of cationic polyacrylamide has a great impact on the flocculent effect, and the cationic degree has little on it. The flocculent mechanism of the inorganic-organic composite flocculant has been discussed on the above result. A conclusion that the inorganic-organic composite flocculant has a higher flocculent efficiency than the polymeric aluminum ferric chloride has been reached. Inorganic-organic composite flocculants are considered to have a good prospect in the field of water treatment...