食品科学 ›› 2013, Vol. 34 ›› Issue (2): 99-104.

• 工艺技术 • 上一篇    下一篇

二次回归正交旋转组合优化麦麸渣吸附铅离子(Pb2+)

陈莉   

  1. 山西省运城学院生命科学系
  • 收稿日期:2011-10-25 修回日期:2012-12-27 出版日期:2013-01-25 发布日期:2013-01-15
  • 通讯作者: 陈莉 E-mail:clsshine@yahoo.com.cn

Study on Biosorption Of Pb2+ by Wheat Bran Residue

  • Received:2011-10-25 Revised:2012-12-27 Online:2013-01-25 Published:2013-01-15

摘要: 采用二次回归正交旋转组合设计方法对麦麸渣吸附Pb2+条件进行优化,建立pH(X1)、温度(X2)、时间(X3)、质量浓度(X4)、加入量(X5)5个因素与吸附率Y的回归模型为:Y=67.56718+9.52691X1+7.35677X 2+0.09693X3-20.27575X4+8.44184X5-4.14591X12+0.36798X22-1.90632X32-1.36466X42-5.18757X52-2.83203X1X2+1.13932X1X3+1.79036X1X4-0.68359X1X5-1.20443X2X3+2.18099X2X4+0.61849X2X5+1.72526X3X4-1.79036X3X5+4.32943X4X5。得出各因素对麦麸渣吸附Pb2+影响顺序为:质量浓度>pH>加入量>温度>时间。从模型可知,在pH=8、温度100℃、时间1h、Pb2+质量浓度20mg/l、加入量0.8g条件下,麦麸渣对Pb2+吸附率最高可达99.99%。验证值为98.91%,与理论值基本一致。麦麸渣对Pb2+的吸附以单分子层的物理吸附为主,Freundlich吸附等温式能较好的描述其吸附热力学情况;麦麸渣对Pb2+吸附先是快速吸附,吸附时间超过60 min后为慢速吸附;麦麸渣对低质量浓度Pb2+溶液的吸附效果好于活性炭。

Abstract: Pb2+ adsorption rate conditions of wheat bran residue optimized through quadratic orthogonal design.A quadratic regression orthogonal model was established to express the relationship between adsorption rate(Y)and five factors including pH (X1), temperature(X2), time(X3), concentration(X4), and addition amount(X5), as shown in the equation, Y=67.56718+9.52691X1+7.35677X2+0.09693X3-20.27575X4+8.44184X5-4.14591X12+0.36798X22-1.90632X32-1.36466X42-5.18757X52-2.83203X1X2+1.13932X1X3+1.79036X1X4-0.68359X1X5-1.20443X2X3+2.18099X2X4+0.61849X2X5+1.72526X3X4-1.79036X3X5+4.32943X4X5.The factor order on Pb2+ adsorption rate from strong to weak was concentration, pH, addition amount, temperature and time. According to this model, adsorption at 0.8g addition amount in 20mg/l for 1h using pH=8 and 100℃ of wheat bran residue revealed the highest adsorption, which was 99.99%. The experiment result was consistent with the theoreticl result of 98.91%. Wheat bran residue on Pb2+ adsorption with single molecule layer absorption dominant, and adsorption isotherm is fit to Freundlich adsorption isotherm. The adsorption rate for wheat bran residue to Pb2+ is quickly first, and then become slowly after more than 60min. Second kinetic model can describe the adsorption kinetics of wheat bran residue more better. In the low concentration of Pb2+ solution, the adsorption of wheat bran residue is better than activated carbon.