Study Of Mesoporous Nano-γ-al₂o₃'s Preparation And Ca²⁺ ,so₄^2-,cl^-'s Adsorption

BaoGang sewage treatment center's wastewater that the reuse rate is not high, and it can not meet the requirements of some enterprises. So it has very important significant that to deal with Baotou Steel Back Water, improve the reuse water quality, increase the recycling rate, reduce the company's reuse water consumption, and reduce the reuse water dosage of enterprises.In this study, norganic aluminum salts and surfactants were used by sol-gel to make high surface area mesoporous nano-γ-Al2O3, the effect of the aging time, calcination temperature and holding time to the synthesis of mesoporous nano-γ-Al₂O₃ were discussed and Nitrogen adsorption Curve,BET specific surface area measurements,XRD and TEM were used as evaluation means. Adsorption methods were used to treat the wastewater, the influence of adsorbent dosage, sorption time, and pH on the remove of Ca²⁺, SO₄^2-, Cl^- were studied, and on this basis L9 (33) orthogonal experiment were done.The results showed that: mesoporous nano-γ-Al₂O₃ powder was synthesized with surface area 522.13m2 / g by using CTAB as surfactant, the optimal synthesis conditions were: The CTAB's concentration was 1g / L, aging time was 24h, calcination temperature was 450℃, the heating rate was 5℃/ min, holding time was 2h.The best removal conditions of Ca2 + were as follows: powder dosage 0.03g/mL, pH value 11, shaking time 15min, the removal rate can be reached to 90%; The powder dosage 0.015g/mL, pH value 5, shaking time 25min, the removal rate can be reached to 97%; The best removal conditions of Cl^-: the amount of powdered 0.03g/mL, pH value 5, shaking time 20min, the removal rate can reached to 55%. Besides, adsorption model was studied. The results showed that: the adsorption of Ca2 +,SO₄^2--,Cl^- by mesoporous nano-γ-Al₂O₃ in neutral conditions at room temperature met the Freundlich adsorption models, and the linear correlation coefficient was above 0.9.The regeneration experiments were done by using mesoporous nano-γ-Al₂O₃ ,and by changing water temperature ,shaking time and pH value which was to detest release conditions of the adsorption of powder. The results showed that: the changed water bath temperature and pH value change in a short period of time (about 25min) are more obvious on desorption, and the best desorption rate can be reached about 70%.In this study, the treated quality can be met the water requirements of clean recycling water which is beneficial to conservation of water resources. There are broad prospects for development.