矿物基多孔颗粒材料净化石英纯化废水研究

Purification of the Wastewater of Quartz Processing by Mineral-based Porous Granulation Material

制备了一种矿物基多孔颗粒吸附材料(MPGM),用于净化富含重金属离子的石英纯化废水.通过BET、SEM及FT-IR等技术分析表明,MPGM具有多孔径分布、大比表面积、低散失率等优良特性;N2吸附-脱附等温线为Ⅲ型,且存在H4型回滞环;官能团以层状硅酸盐矿物的基团为主.研究了吸附剂用量、初始p H值及时间对MPGM吸附Fe、Zn、Mn、As的影响,结果表明,4种金属离子浓度分别由77.760、3.700、2.789和0.963 mg·L-1吸附净化为3.421、0.574、0.126和0.034mg·L-1.对使用过的吸附材料利用1.0 mol·L-1的Na Cl脱附12 h,重复利用5次后仍维持理想的吸附水平.吸附机制研究表明,吸附体系均符合Langmuir吸附等温线模型及准一级动力学模型/准二级动力学模型;ΔGθ<0、ΔHθ>0、ΔSθ>0,说明吸附过程为吸热反应,且在15~45℃温度下有利于反应顺利自发进行.

A mineral-based porous granulation material( MPGM) was prepared for absorbing the heavy metal ions from quartz processing wastewater. Analytic results of the MPGM were illustrated by the techniques of BET,SEM and FT-IR,which revealed the excellent properties of multi-aperture distribution,large specific surface area,low loss ratio and so on; the N2adsorption-desorption isotherm was type-Ⅲ with H4 hysteresis loop; the functional groups were dominated by groups of layer silicate mineral. A batch adsorption study was carried out with varied adsorbent dosage,initial p H and reaction time. The results showed that the residual ion concentrations of Fe,Zn,Mn and As were decreased from 77. 760,3. 700,2. 789 and 0. 963 mg·L- 1to 3. 421,0. 574,0. 126 and0. 034 mg·L- 1,respectively. MPGM might be re-utilized after desorption by 1. 0 mol·L- 1Na Cl for 12 hours,and the ideal adsorption performance was maintained after 5 recyclings. The adsorption equilibrium and kinetics followed Langmuir and typical pseudo-firstorder / pseudo-second-order adsorption models. Thermodynamic parameters of ΔGθ< 0,ΔHθ> 0,ΔSθ> 0 showed that the adsorptions were spontaneous and endothermic processes in the temperature range of 15-45℃.