蔗渣木质素对溶液中重金属离子的吸附性能

Absorption properties of bagasse lignin on heavy metal ion in solution

研究了蔗渣木质素在不同的吸附时间、pH值、溶液浓度、木质素用量等条件下对Pb2+、Cd2+、Hg2+3种重金属离子的吸附作用,探讨了蔗渣木质素的等温吸附规律及吸附性能。实验结果表明:木质素吸附平衡时间约为15 min;溶液pH值是影响木质素对重金属吸附能力的主要因素,吸附量随pH值升高而增加;木质素对3种重金属离子皆有一定的吸附作用,吸附量次序为Pb2+(21.62 mg/g)>Hg2+(7.65mg/g)>Cd2+(3.32 mg/g)。Redlich-Peterson与Langmiur等温吸附模型可以较好的描述蔗渣木质素对3种重金属离子的吸附特性,其吸附过程属于优惠吸附。本结果可为用蔗渣木质素开发吸附重金属食品添加剂提供科学依据。

Absorption effects of bagasse lignin on Pb^2＋ Cd^＋ and Hg^2＋ in different absorption times, pH values, solution concentrations and amount of lignin were studied, and isothermal absorption laws and absorption properties were also discussed. The results were as following： 1 ） Absorption equilibrium time of lignin was 15 min; 2） pH of solution was the main factor for the effects of lignin on such heavy metal ions as Pb^2 ＋ , Cd^2＋ and Hg^2 ＋ , and the absorption amounts went up with the increase of pH ; 3 ） Lignin had certain absorption function on three heavy metal ions,and the amounts of absorption were Pb^2＋ （21.62 mg/g） 〉 Hg^2＋ （7.65 mg/g） 〉 Cd^2＋ （3.32 mg/g. The absorption properties of bagasse lignin on heavy metal ions can be well described by Redlich-Peterson and Langmuir isothermal absorption models, and the process was favorable absorption. This study will provide sciemific basis on developing food additives of adsorption heavy metals from bagasse lignin