Laboratory of Storage and Valorization of Renewable Energies, Faculty of Chemistry, Algiers, Algeria.
J Environ Health Sci Eng. 2014 Jan 8;12(1):13. doi: 10.1186/2052-336X-12-13.
Ni2+ is a highly toxic above 0.07 mg/L and its removal is of high significance. The biosorption of Ni2+ onto medlar male flowers (MMF) was studied in relation with the physical parameters like pH, contact time, biosorbent dosage, Ni2+ concentration and temperature. The interaction biosorbent-Ni2+ was examined by the FTIR technique. The equilibrium was achieved within 40 min and the data were well fitted by the Langmuir and Redlich-Peterson (R-P) models. The maximum Ni2+ uptake capacity was 17.073 mg/g at 25°C and the Ni2+ removal follows a pseudo-second order kinetic with activation energy of 13.3 kJ/mol. The thermodynamic parameters: ΔS°, ΔH° and ΔG° showed that the biosorption was spontaneous and endothermic. MMF was used as a post treatment technique and the biosorption was coupled with the visible light driven Ni2+ reduction over the spinel ZnMn2O4. The effect of the pH, ZnMn2O4 loading and light intensity on the photoactivity was investigated. 77.5% of Ni2+ was reduced after ~140 min under optimal conditions. The Ni2+ removal reached a rate conversion of 96% of with the coupled system biosorption/photocatalysis is very promising for the water treatment.
镍（Ni2+）的毒性很强，超过 0.07 毫克/升时就需要高度重视。本研究采用枸杞雄花（MMF）去除废水中的镍，考察了 pH 值、接触时间、生物吸附剂用量、镍浓度和温度等物理参数对镍吸附的影响。采用傅里叶变换红外光谱（FTIR）技术对生物吸附剂-镍的相互作用进行了研究。结果表明，在 25°C 下，平衡时间为 40 分钟，Langmuir 和 Redlich-Peterson（R-P）模型均能很好地拟合吸附数据。最大镍吸附容量为 17.073mg/g。镍的去除遵循拟二级动力学，表观活化能为 13.3kJ/mol。热力学参数ΔS°、ΔH°和ΔG°表明，吸附过程是自发和吸热的。MMF 可作为后处理技术，将吸附与尖晶石 ZnMn2O4 可见光驱动的镍还原相结合。考察了 pH 值、ZnMn2O4 负载量和光强对光活性的影响。在最佳条件下，约 140 分钟后，77.5%的镍被还原。在耦合系统吸附/光催化作用下，镍的去除率达到 96%，该方法有望用于水处理。
