交联羧甲基罗望子胶对Cd2+的吸附研究

以罗望子胶原粉(TKP)为基料,氯乙酸钠(SMCA)为羧甲基醚化剂,环氧氯丙烷(ECH)为交联剂制备了取代度(DS)为0.42,0.64和0.88的3种交联羧甲基罗望子胶(CCMTKP),探究其对水溶液中Cd2+的吸附行为。结果表明:适宜吸附的pH值范围为2~6;吸附剂较佳用量为0.5%(质量分数);3种CCMTKP对Cd2+的吸附在15min内达到平衡,遵从二级动力学方程;吸附符合Langmuir等温吸附,CCMTKP对Cd2+的最大吸附量为64.10mg/g;再生后的CCMTKP吸附性能良好,脱吸附率高,有望作为Cd2+的吸附剂使用。

Adsorption research of Cd2+ by crosslinked carboxymethyl tamarind

With tamarind kernel polysaccharide （TKP） as matrix, sodium monochloroacetic acid （SMCA） as etherifying agent and epichlorohydrin （ECH） as crosslinking agent, three kinds of crosslinked carboxymethyl tamarind （CCMTKP） samples with degree of substitution （DS） 0. 42, 0.64 and 0.88 were prepared, and used to adsorb Cd2＋ from aqueous solution. The ap- propriate range of pH value was 2~ 6. The optimal adsorbent dosage was 0. 5~ （w/w）. The adsorption capacity rapidly reached equilibrium within 15 min and adsorption followed second-order kinetic equation. The adsorption of Cd2＋ is well fol- lowed as the Langmuir isotherm and the maximum adsorption capacity （Qm） was 64.10 mg/g. The regeneration study indicates that CCMTKP could be used repeatedly without significantly changing their adsorption capacities, which indicates that CCMT- KP has the potential to treat waste water containing Cd2＋.