Study On Preparation And Mechanical Properties Of Alkali Leaching Of Lead Zinc Slag Geopolymer

The geopolymer,an inorganic polymer material,was prepared with silicon-aluminum-containing material in the condition of alkali-activated.It is a three-dimensional netted structural contains silicon-oxygen and aluminum-oxygen tetrahedron.This kind of material has some special properties,such as the effectiveness of the mechanism?acid and alkali resistance?refractory and high temperature resistance,high strength and rapid hardening.In addition,this process is simple,much more sources of raw material,low energy consumption and low pollution.It is a green material that meets the criteria of sustainable development and in line with the country's advocacy of the use of resources to maximize the purpose.Geopolymer have a very good application prospect in industrial production,construction,aerospace and other industries.This paper taked the alkaline leaching lead-zinc slag,metakalin,water glass solution and sodium hydroxide as the main raw materials were prepared on the alkaline leaching lead-zinc slag geopolymer by alkali leaching process,and researched on the optimal proportion of it;The influence of the strength of geopolymer by calcined activated the alkaline leaching of lead-zinc slag;By modulus values of water-glass and alkali activator admixture as variable,the optimization of alkaline leaching lead-zinc slag geopolymer was realized with response surface methodology,also,a regression equation is established which suitable to the alkali activator admixture and modulus values of water-glass for strength of geopolymer.Finally,through micorostructure analysis the reaction mechanism of geopolymer which characterized by XRD and SEM.The specific studies were as belows:(1)Experimental study on preparation of alkaline leaching lead-zinc slag geopolymerThe influences of alkali leaching amount of lead-zinc slag,modulus values of water-glass and alkali activator admixture on the strength of the geopolymer were investigated by orthogonal test.The test results showed that the optimum ratio of compressive strength of alkaline leaching lead-zinc slag geopolymer was 49.6MPa when the modulus values of water-glass was 1.2,the alkali activator admixture was 65% and alkali leaching amount of lead-zinc slag was 45%;The optimum ratio of flexural strength of alkaline leaching lead-zinc slag geopolymer was 7MPa when the modulus values of water-glass was 1.2,the alkali activator admixture was 65% and alkali leaching amount of lead-zinc slag was 35%;The alkali activator admixture was the first factor that affects the strength.(2)Calcined activationThe effect of calcined activation on the strength of alkaline leaching lead-zinc slag geopolymer is studied systematically.The results show that the activity of alkaline leaching lead-zinc slag enhanced by calcined activation.The optimum calcination temperature is 750? and the calcination time is 60 min.(3)Respose surface design testThe test results showed that the optimum ratio of compressive strength of alkaline leaching lead-zinc slag geopolymer was 60.8MPa by response surface design test when the modulus values of water-glass was 1.1,the alkali activator admixture was 68%.The study have certain significance in prediction by the regression equation between modulus values of water-glass and alkali activator admixture for the strength of alkaline leaching lead-zinc slag geopolymer.At the same time,the higher modulus values of water-glass,the lower its strength;the higher alkali activator admixture,the higher its strength.(4)Polymerization mechanism analysis of alkaline leaching lead-zinc slag geopolymerThe block by orthogonal for alkaline leaching lead-zinc slag geopolymer which analyzed by SEM and XRD.The SEM picture shows the alkaline leaching lead-zinc slag geopolymer are tight and form granular crystals substance,which has good compression reistance;XRD pattern shows that the metakaolin and alkaline leaching lead-zinc slag were subjected to polymerization under alkali activation conditions,and a more complicated structural and more stable in properties of new inorganic polymer is generated,such as Natriuretic zeolite(Na2Al2Si3O10·2H2O)and Sodium polysilicate(Na6Si8O19).