三乙烯四胺改性风化煤对废水中Ni2+的吸附机制

为提高风化煤对Ni2+的吸附性能，以XWC（新疆风化煤）为基体，TETA（三乙烯四胺）为改性剂，采用交联反应联合超声波振荡制备ACA（胺化煤基吸附剂），利用SEM（扫描电镜）等手段对其进行表征，并考察了体系pH、吸附剂用量、反应时间及溶液初始ρ（Ni2+）对吸附过程的影响，通过吸附动力学和吸附等温模型对吸附机制进行描述.结果表明，TETA中的多乙烯多胺基成功接枝到煤粉表面使风化煤的表面颗粒增多，比表面积由6.875 m2/g减至3.440 m2/g，孔容由0.011 cm3/g减至0.005 cm3/g.在pH为8.0、ACA用量为0.4 g时吸附效果最好.ACA和XWC对Ni2+的吸附过程均符合准二级动力学方程及Langmuir吸附等温模型.拟合得ACA的饱和吸附量为188.68 mg/g，较改性前提高了5.1倍.研究显示，ACA处理ρ（Ni2+）范围为200~1 000 mg/L的废水时，对Ni2+的去除率稳定在95%以上. 

Adsorption of Ni2+ in Wastewater by Triethylenete-Tramine Modified Weathered Coal

Aminated coal-based adsorbent (ACA) was synthesized by using crossing reaction combined with ultrasonic vibration with Xinjiang weathered coal (XWC) as the carrier and triethylenete-tramine (TETA) as the modifier. The ACA was characterized by scanning electron microscope (SEM). The effect of solution pH, adsorbent dosage, reaction time, and initial ρ(Ni2+) on adsorption capacity were also investigated. Moreover, adsorption kinetics and adsorption isotherm models were used to describe adsorption mechanism. The results showed that the number of particles on weathered coal increased after the poly vinyl polyamine in TETA being successfully grafted onto the coal surface. Specifically, the specific surface area decreased from 6.875 m2/g to 3.440 m2/g and the pore volume decreased from 0.011 cm3/g to 0.005 cm3/g. The pH of 8.0 and ACA mass of 0.4 g leaded to an optimum adsorption effect. The adsorption kinetics of ACA and XWC on Ni2+ were fitted well by the pseudo-second-order kinetic model and Langmuir isotherm model. The adsorption capacity of ACA was 188.68 mg/g, which was improved by 5.1 times after modification. The removal rate of Ni2+ was reached to >95%, when the ρ(Ni2+) range from 200 mg/L to 1000 mg/L with ACA treatment.