Study On Preparation And Purification Effect Of Borosilicate Metal Salt-Chitosan Composite

Flocculation method is widely used in water treatment because of its simple operation and good purification effect.In the flocculation process,the quality of flocculants is the key factor that affects the whole process.This article use NaSiO₄,Al₂?SO₄?₃,Fe₂?SO₄?₃?or Zn?SO₄??,Na₂B₄O₇,CTS as the main raw materials to prepare PSAFB-CTS and PSAZB-CTS.We characterize the structure of the two composite flocculants and study on their purification effect.The main research contents and results of the study are as follows:The preparation of two composite flocculants.In the preparation process,two kinds of kaolin simulated water were used as treatment object.This article mainly studied the n?Al?/n?Si?,n?Fe?/n?Si?or n?Zn?/n?Si?,n?B?/n?Si?,m?CTS?/m?Si?,ripening pH,curing time and dosage to impact the flocculation effect of PSAFB-CTS and PSAZB-CTS.The results show that the optimal conditions for the preparation of PSAFB-CTS are:n?Al?/n?Si?=0.4,n?Fe?/n?Si?=0.1,n?B?/n?Si?=0.2,ripening pH=2,m?CTS?/m?Si?=0.08,ripening time was 1d.The results show that the optimal conditions for the preparation of PSAZB-CTS are:n?Al?/n?Si?=0.4,n?Zn?/n?Si?=0.3,n?B?/n?Si?=0.2,ripening pH=2,m?CTS?/m?Si?=0.08.In this paper,FTIR,XRD and SEM were used to analyze the characterization of two kinds of composite flocculants.FTIR shows that the two composite flocculants have new absorption peaks relative to B-polysilicate metal salts and chitosan;From the X-ray diffraction of polysilicate,CTS and composite flocculants,it can be seen that the positions of characteristic peaks of these three compounds are not in the same range,and the characteristic peaks of Al₂?SO₄?,Fe₂?SO₄?,ZnSO₄,Na₂B₄O₇,Al₂O₃,Fe₂O₃,Fe₃O₄,and SiO₂ are basically not identified;SEM observation of two composite flocculants.The shape of PSAFB-CTS is uniform,compact,sheet or needle-like in shape and cross-linked,which enhances the adsorption capacity.PSAZB-CTS mainly exist in the form of clusters,and the surface is compact,which has a strong entrapping effect.Taking actual river water as the object of treatment,the comparative tests of two composite flocculants and their monomers and PAP were studied.The results showed that PSAFB-CTS had the best effect in removing turbidity,COD and chlorophyll a,and the highest removal rates were 97.72%,60.2%and 99.64%when the dosage is7mL/500m L.PSAZB-CTS has the best removal effect in terms of chroma removal.When the dosage is 7m L/500,the highest chroma removal rate is 66.05%.In addition,the concentration of residual aluminum by PSAFB-CTS and PSAZB-CTS was 0.10mg/L and 0.11 mg/L,meeting standard requirements that the content of aluminum is less than 0.2mg/L.The results show that PSAFB-CTS and PSAZB-CTS are efficient,safe and environmentally friendly flocculants,which have broad prospects of research and popularization value.