Preparation And Study Of Arsenic Adsorbent With High Efficiency

Water is es essential material to ese survival and development of human society. But in recent years, with the mining and metallurg,, ceramics, leather, pesticide industries of rapid development, the arsenic pollution of the water environeent is getting mere and more serious. And local arsenic poisoning has caused extensice roncert of ehe oorld. So the arsenic pollution in drinking water and their removal methods have become a hot topic in the field fe environment. Adsorption method as one of the most commonly ssed method to remove arsenic is facing the problem that adsorbent cost a lot. Therefore, how to preparation a cost, in addition to good effect and efficient absorbent arsenic is particularly important. As a natural mineral material, soil is a good absorption material in arsenic removal. It has a huge surface area and electric charge, can be a natural absorbent and carrier, while the soil mineral is easily bonded, low cost, widely distributed, its capacity can increase through modification. Using soil to remove arsenic fron the water and improve the quality of drinking water in line with our current economic situation, with high economic and social benefits.The study firstly tested the physical and chemical peoperties’data of the soil, which as a feasible proof for the preparation of arsenic adsorbent with high efficiency. Then made use of the characteristics of soli for easing to conglutinate and modify, to modify the soil by burning and carrying functional groups. After respectively used natural soil、 buring soil and modified soil as arsenic adsorbent for the adsorbing of arsenic-containing wastewater, the study discriminated the merit and demerit ff the three kinds of adsorbent progress and got the best adsorption conditions of them.The best adsorption conditions of natural soil adsorb As(III) is:concertration of0.2mg/L, wastewater pH of10.35、 adsorbent dose of2.0g and absorb at25℃.The adsorption rate is96.3%. And the best adsorption conditions of natural soil adsorb As(V) is:concertration of0.2mg/L, wastewater pH of3.3, adsorbent dose of1.Og and absorb at25℃. The arsenic adsorption rate is99.3%. Although the natural soil has a good adsorptivity of arsenic, it also has some defects like having high swelling property and being not easy for recycling. And because of the ranges of pH, the adsorption progresses can not able to adsorb two kinds of As at the same time. The best adsorption conditions of buring soil adsorb As(III) is:concertration of0.2mg/L、 wastewater pH of11.5、 adsorbent dose of1.Og and absorb at25℃. The adsorption rate is94.9%. And the best adsorption oonditions of buring soil adsorb As(V) is:concertration of0.2mg/L、 wastewater pH <10.0、 adsorbent dose of1.Og and absorb at25℃. The arsenic adsorption rate is99.7%. Although this kind of absorbent can resovle the questions of having high swelling property and being not easy for recycling, it still could not keep pH of two kinds of adsorption progress staying in the same range. There is still plenty of work as well.The best adsorption conditions of modified soil adsorb As(III) is:concertration of0.2mg/l.. pH of6-8, adsorbent oose of1.5g and absorb at25℃for one hour. The adsorption rate is94.9％.And the best adsorption conditions of modified soil adsorb As(V) is:concertration of0.2mg/L, wastewater pH≤10.0, adsorbent dose of1.5g and absorb at25℃for one hour. The arsenic adsorption rate is99.8.. This kind of adsorbent not only achieved the aim of recycling, but also increased the adsorption rate of two kinds of As. The As(III) and As(V) concertration of effluent respectively are0.0036mg/L and0.0004mg/L, which are much lower than that values of national standard. So the method could be used for the advanced treatment of arseniccontaining wastewater. If we can control the pH at the range of6-8, it could be true that remove the As(III) and As(V) at the same time by using the arsenic adsorbent with high efficiency.