摘要
为寻找1种高效且价格低廉含Zn^(2+)废水的生物吸附剂,资源化利用香菇废弃物,以聚乙烯醇(PVA)、海藻酸钠(SA)包埋香菇残粉制成PVA-SA香菇小球。进行了以PVA、SA、香菇残粉、一次交联时间、磷酸盐浓度、二次交联时间为影响因素的6因素3水平正交实验来确定包埋香菇的最优方案,得到PVA-SA包埋香菇最佳配方是8%PVA+2%SA+3%香菇残粉,在质量分数为2%CaCl_(2)饱和硼酸中一次交联12 h后,在质量浓度为3 g/L磷酸盐溶液中交联8 h。最佳香菇小球对Zn^(2+)平衡吸附时间为1 h,伪二级动力学模型能很好地拟合包埋香菇对Zn^(2+)的吸附动力学过程,相关系数R^(2)为0.999 5,速率参数k_(2)为0.395 2 g/(mg·min)。Langmuir和Freundlich模型都能较好地描述Zn^(2+)的等温吸附过程,Langmuir吸附等温模型推算出在20、30、40℃时香菇小球对Zn^(2+)的最大吸附量为5.82、7.52、9.92 mg/g。在吸附热力学研究中,20~40℃之间,△G^(θ)=-18.3~-21.4 kJ/mol、△H^(θ)=28.6 kJ/mol、△S^(θ)=159.9 J/(mol·K),说明包埋香菇小球对Zn^(2+)的吸附是自发的、吸热的过程。
Lentinus edodes residue is selected as an efficient biosorbent for Zn^(2+)wastewater, polyvinyl alcohol(PVA) and sodium alginate(SA) are used to entrap Lentinus edodes.A 6-factor 3-level orthogonal experiment with PVA, SA, shiitake mushroom powder, primary cross-linking time, phosphate concentration, and secondary cross-linking time as the influencing factors was carried out to determine the optimal plan for embedding shiitake mushrooms. The best formula for PVA-SA embedded mushrooms is the mixer of 8%PVA+2%SA+3%Lentinus edodes powder, which is cross-linked in 2%CaCl_(2)saturated boric acid for 12 h, then cross-linked in 3 g·L^(-1)phosphate for 8 h. Zn^(2+)adsorption equilibrium time is 1 h for this selected immobilized Lentinus edodes, and the pseudo-second-order kinetics model can well fit the kinetics of zinc adsorption with the correlation coefficient R^(2)0.9995 and the rate parameter k_(2)is 0.395 2 g·mg^(-1)·min^(-1). Both Langmuir and Freundlich adsorption isotherm model fit the adsorption thermodynamics process of zinc well. Langmuir adsorption isotherm model show that the maximum adsorption capacity of zinc is 5.82,7.52,9.92 mg·g^(-1)at 20, 30,40 ℃ respectively. In the study of adsorption thermodynamics, △G^(θ)=-18.3~-21.4 kJ·mol^(-1), △H^(θ)=28.6 kJ·mol^(-1), △S^(θ)=159.9 J·mol^(-1)·K^(-1), indicating that the adsorption of zinc by immobilized Lentinus edodes is a spontaneous, endothermic and randomness process.
作者
马培
吴烨
陈纳
马梦娟
陈锋
丁亚磊
MA Pei;WU Ye;CHEN Na;MA Mengjuan;CHEN Feng;DING Yalei(School of resource and environment,Henan university of Engineering Zhengzhou 451191)
出处
《工业安全与环保》
2022年第3期88-92,98,共6页
Industrial Safety and Environmental Protection
基金
国家自然科学基金青年科学基金(41401549)
河南省高等学校重点科研项目(20B610003)
河南工程学院培育基金项目(PYXM202011)。
关键词
ZN
包埋
热力学
动力学
Lentinus edodes residue Zinc
entrapment
thermodynamics
kinetics
