(武漢工程大學(xué) 化工與制藥學(xué)院 綠色化工過程教育部重點(diǎn)實(shí)驗(yàn)室，武漢 430074)
摘 要: 制備改性甘蔗渣并探討了其對Pb2+的動態(tài)吸附，在單一體系中研究填充粒徑、溶液初始濃度和流速等對Pb2 +動態(tài)吸附的影響，考察填充柱的重復(fù)使用情況；在兩組分體系中考察Cu2+和Zn2+對Pb2+動態(tài)吸附的影響。結(jié)果表明：單一體系中，粒徑、流速及初始濃度對Pb2+的動態(tài)吸附影響較小(吸附容量：118.9~148.6 mg/g)，填充柱可在較寬的實(shí)驗(yàn)條件下使用，改性甘蔗渣可反復(fù)使用。兩組分體系中，改性甘蔗渣對Pb2+的吸附親和力顯著高于對Cu2+和Zn2+的，吸附中存在明顯的競爭取代過程；改性甘蔗渣填充柱可實(shí)現(xiàn)Pb2+、Cu2+和Pb2+、Zn2+的選擇性分離。金屬離子的吸附過程伴隨著H+的釋放過程，酸度越高，填充柱對重金屬離子的吸附容量越小。
關(guān)鍵字: 固定床；吸附；甘蔗渣；穿透曲線；競爭吸附
（Key Laboratory for Green Chemical Process, Ministry of Education, School of Chemical Engineering and Pharmacy,
Wuhan Institute of Technology, Wuhan 430074, China）
Abstract:Pyromellitic dianhydride modified bagasses were used as adsorbents for lead ion removal in a fixed bed. The effect of the filler particle size，initial concentration and flow rate on the adsorption of lead ions under continuous model in one component system was investigated. Furthermore, the reuse ability of the fixed bed was studied. The effect of co-ions of Cu2+ and Zn2+ on the adsorption of Pb2 + in the binary system was also investigated. The results show that the particle size, initial concentration and flow rate have little effects on the adsorption of Pb2+, and the fixed bed can used repeatedly under wide experimental conditions. Competitive adsorption results in the binary system show that the modified bagasse has higher affinity toward Pb2 + than Cu2+ and Zn2+, and Pb2+ can be selectively removed from the Pb2+/Cu2+ and Pb2 +/Zn2+ binary system. The pH experiment shows that adsorption of the metal ions is accompanied by the release of H+, and acidity has adverse effect on the adsorption of heavy metal ions.
Key words: fixed bed; adsorption; bagasse; breakthrough curve; competitive adsorption
