改性累托石对水溶液中Cr(Ⅵ)的吸附  

ADSORPTION OF MODIFIED RECTORITE FOR Cr(Ⅵ) FROM AQUEOUS SOLUTION

作　　者：黄韵[1] 马晓燕[1] 刘海林[1] 袁莉[1] 

机构地区：[1]西北工业大学理学院应用化学系,西安710072

出　　处：《硅酸盐学报》2005年第2期197-201,共5页Journal of The Chinese Ceramic Society

摘　　要：用十二烷基二甲基苄基氯化铵[C12H25(CH3)2(C6H5CH2)NCl,1227]、十六烷基三甲基溴化铵[C16H33(CH3)3NBr,1631]、十八烷基三甲基溴化铵[C18H37(CH3)3NBr,1831]3种表面活性剂改性天然粘土累托石(rectorite,REC),得到3种有机改性累托石:1227 REC,1631REC和1831 REC。用3种有机改性累托石对水溶液中无机重金属离子Cr(Ⅵ)进行吸附实验,考察了 pH值、吸附时间、温度等因素对吸附效果的影响。同时,用3种吸附累托石1227 REC Cr,1631 REC Cr和1831 REC Cr对Cr(Ⅵ)进行解吸试验,考察了pH值对解吸效果的影响。结果表明:3种吸附剂在室温下达到满意吸附效果的pH值为6,平衡时间分别为30,20,20 min。在该条件下被吸附Cr(Ⅵ)的量与吸附前相比分别为80.2%,95.5%和97.6%,且3种吸附剂对Cr(Ⅵ)均是 Langmiur单分子吸附。当 pH值为 10时,3 种吸附累托石解吸出Cr(Ⅵ)的量对其原吸附量相比分别是89.2%,96.3%和97.7%。The natural rectorite(REC) was modified with dodecyl benzyl dimethyl ammonium chloride [C_(12)H_(25)(CH_3)_2·(C_6H_5CH_2)NCl,1227], hexadecyl trimethyl ammonium bromide[C_(16)H_(33)(CH_3)_3NBr,1631] and octadecyl trimethyl ammonium bromide [C_(18)H_(37)(CH_3)_3NBr,1831] as surfactants, respectively and three kinds of organic-modified rectorite:1227-REC,1631-REC,1831-REC were obtained, which were then used as adsorbents for Cr(Ⅵ) ion in water, and then three kinds of adsorbed rectorite:1227-REC-Cr, 1631-REC-Cr and 1831-REC-Cr which were used in desorption experiment. The effects of pH value, time of adsorption and temperature on the adsorption, and the effect of pH value on desorption were tested. The results show that the pH value of the satisfactory effect at room temperature obtained for 3 different absorbents is 6, the time of absorption is 30, 20 and 20 min and absorption efficiency of Cr(Ⅵ) ion removed from water is 80.2%, 95.5% and (97.6%), respectively. The adsorption model is Langmuir type for all 3 kinds of absorbents. When the pH value is 10, the desorption efficiency of Cr(Ⅵ) ion desorbed from adsorbed rectorites are 89.2%, 96.3% and 97.7%, respectively.

关 键 词：表面活性剂 改性累托石 六价铬离子 吸附 解吸 

分 类 号：TQ424.24[化学工程]