| It can cause significant damage to the ecological environment and human health, if waste water containing radioactive elements into the water and soil, so its emergency disposal technology and material is popular. 137 Cs is the most common element in nuclear applications, adsorption is the most simple, effective and practical method on the treatment to it. The key is the pore structure and adsorption efficiency(adsorption capacity, adsorption rate, removal efficiency and cost performance) of adsorbent. Zeolite and diatomite has the advantage of removal for Cs+ with its natural structure. It can significantly improve the adsorption capacity and flocculating rate after surface modification, and it becomes an important research field which used for adsorption of Cs+ from wastewater.In this paper,we prepared six kinds adsorbent by aqueous solution polymerization and solution dispersion method. We loaded the organic functional groups on diatomite surface with AM and CTS; modified diatomite with commercial PAM emulsion(cation, anion, nonionic); modified zeolite with chitosan. The influence of various synthesis conditions to the new function groups and surface properties of diatomite and zeolite, and its adsorption efficiency of Cs+ was investigated. The specific surface area of CWOPAM is 116 m2/g, pore diameter is 7nm~9nm, maximum adsorption capacity of Cs+ is 151.6mg/g. The as-prepared samples were characterized by FT-IR, SEM, BET. The samples showed function groups as-NH2?C=O?-OH?-CH3?-CH2 after modified.In this dissertation, adsorption properties to Cs+ of as-prepared samples and the influence law was investigated. The pH value, initial concentration, adsorbent amount, adsorption time effect the adsorbents for the removal efficiency of Cs+. The pH effect as the main factor. There are two maximum removal rate of Cs+ as pH of solution change; Adsorption capacity of samples show rapid increase, with the increase of Cs+ ion initial concentration, and then growth slowing; Increase the dosage of adsorbent and the extension of adsorption time, the removal rate of Cs+ was gradually increased, when dose of 40mg(100ml Cs+ solution), action time for 30 min, removal can reach 98%. The largest adsorption capacity of CWO-PAM/diatomite, PAM/diatomite, CTS/diatomite, CTS/zeolite is 151.6mg/g?136.3 mg/g?148.2mg/g?153.6 mg/g.We tested the sample of before and after adsorption with FT-IR and zeta potential technology, and explored the mechanism of adsorption preliminary. The four adsorbent have both of physical adsorption and chemical adsorption to Cs+, and CTS/zeolite has ion exchange action to Cs+. |
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