金属氧化物纳米颗粒对磷的吸附及回收潜力

发布时间：2018-05-26 00:41

本文选题：纳米颗粒 + nMgO　；参考：《中国环境科学》2017年07期

【摘要】：比较4种金属氧化物纳米颗粒(nMgO,nAl_2O_3,nTiO2和nFe_2O_3)对水体P的吸附性能,并探讨了pH、吸附时间、共存离子等因素对nMgO吸附P的影响,用XRD和XPS分析了nMgO对P的吸附机制,最后通过小青菜盆栽实验法探讨nMgO从养殖废水中吸附回收P的应用潜力.结果发现,在pH3.0~8.0范围内,nMgO对P的吸附量显著高于nAl_2O_3、nTiO_2和nFe_2O_3,4种纳米颗粒对P的吸附量分别可达40、31.77、15.93和13.08mg/g.吸附后P的解吸可逆性较差.nMgO对P的吸附能在0.5h内达到吸附平衡,P的吸附符合准二级动力学过程.体系共存的等量F~-、Cl~-、NO_3~-、SO_4~(2-)、Na~+、K~+和NH_4~+离子对nMgO吸附P无显著影响,Mg~(2+)和Ca~(2+)离子对P吸附具有促进作用.nMgO对P的吸附等温线可用Langmuir模型描述,最大吸附量达139.3mg/g.XRD和XPS分析表明,nMgO对P的吸附是伴有静电吸引的以表面络合沉淀反应为主的吸附过程.nMgO能有效地从养殖废水中吸附回收P,吸附P的nMgO作为肥料,能使小青菜干物质量从0.31g/kg土增加到0.96g/kg土.
[Abstract]:The adsorption properties of four kinds of metal oxide nanoparticles (nMgONAl _ 2O _ 3nTiO _ 2 and nFe _ 2O _ 3) on P in water were compared. The effects of pH, adsorption time and coexisting ions on the adsorption of P by nMgO were discussed. The mechanism of P adsorption by nMgO was analyzed by XRD and XPS. Finally, the application potential of nMgO in recovering P from culture wastewater was discussed by pot experiment. The results show that the amount of P adsorbed by nMgO in the range of pH3.0~8.0 is significantly higher than that of nAl2O3nTiO2 and nFe2O3s in the range of pH3.0~8.0. The desorption reversibility of P after adsorption is poor. The adsorption energy of P can reach the adsorption equilibrium within 0.5 h. The adsorption of P conforms to the quasi-second-order kinetic process. The isotherm of P adsorbed by nMgO can be described by Langmuir model. The isotherm of P adsorbed by Ca~(2 ions can be described by Langmuir model, and the isotherms of P adsorption by Ca~(2) ions have no significant effect on the adsorption of nMgO by K ~ and NH ~ (4 ~ +) ions, and the isotherm of P adsorption can be described by Langmuir model, and the isotherm of P adsorption can be described by Langmuir model. The results of 139.3mg/g.XRD and XPS analysis showed that the adsorption of P by nMgO was an adsorption process with electrostatic attraction, which was mainly composed of surface complexation precipitation reaction. NMgO could effectively adsorb and recover P from aquaculture wastewater and adsorb nMgO of P as fertilizer. It can increase the dry weight of green vegetables from 0.31g/kg soil to 0.96g/kg soil.
【作者单位】：西北农林科技大学资源环境学院;西北农林科技大学理学院;School
【基金】：中央高校基本科研业务费项目(2014YB064) 美国农业部环保署项目(USDA-NRCS#69-3A75-10-156)
【分类号】：X52;X713

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