PEI功能化秸秆生物炭对水中Cr6+的吸附性能

Adsorption of Cr6+ on Polyethyleneimine-functionalized Straw Biochar from Aqueous Solution

选取玉米秸秆为原料,经过缺氧炭化制备玉米秸秆生物炭,并以聚乙烯亚胺(PEI)负载于生物炭表面,制备PEI功能化秸秆生物炭,研究了其对水中Cr^6+的吸附性能和机理.结果表明,在吸附剂添加量相等条件下,PEI碱性生物炭(PBC)对Cr^6+的吸附效率明显高于PEI酸性生物炭(HBC)和原始生物炭(CBC).PBC对水中Cr^6+的最大吸附量为386.3 mg/g,吸附平衡时间为300 min;当pH=2.0左右时,对Cr^6+的吸附效率最大达到95.94%.因此,PBC可作为一种高效去除水中Cr^6+的吸附剂.

To study the properties of straw biochar composites and the adsorption characteristics of Cr^6+ from water,corn stalks were selected as raw material and corn stalk biochar was prepared by anoxic carbonization and loaded on the surface of biochar with polyethyleneimine(PEI).PEI-functionalized straw biochar was prepared,and its adsorption performance and the mechanism of Cr^6+ adsorption were characterized.The results showed that the adsorption efficiency of PEI alkaline biochar(PBC)on Cr^6+ was significantly higher than that of PEI acidic biochar(HBC)and raw biochar(CBC)under the same conditions of adsorbent addition.The maximum adsorption capacity of Cr^6+ on PBC from aqueous solution was 386.3 mg/g,and the adsorption equilibrium time was 300 min.When the pH was approximately 2.0,the adsorption efficiency of Cr^6+ reached 95􀆰94%.Therefore,PBC can be used as an adsorbent for the efficient removal of Cr^6+ in water.