粒状羟基氧化铁对废水中硝酸盐的吸附  

Adsorption of nitrate on granular ferric hydroxide from simulated wastewater

作　　者：霍蕾[1] 杨琦[1] 尚海涛[1] 

机构地区：[1]中国地质大学(北京)水资源与环境学院,北京100083

出　　处：《环境工程学报》2012年第9期3058-3062,共5页Chinese Journal of Environmental Engineering

基　　金：国家自然科学基金资助项目(40102027;50578151);北京市自然科学基金资助项目(8052017;8092025);北京市教委产学研项目(51900265005);国家"水体污染控制与治理"科技重大专项(2009ZX07207-008;2009ZX07419-002;2009ZX07207-001)

摘　　要：本实验研究了粒状羟基氧化铁(GFH)对人工配制含氮废水中NO3--N吸附的影响因素、吸附等温线和吸附动力学。结果表明,GFH的吸附平衡时间为80 min,增加NO3--N溶液的初始浓度,去除率下降;pH值为5时GFH对NO3--N的吸附能力最强,pH值升高和降低,吸附能力均下降;GFH对NO3--N的吸附能力随着温度的升高略有降低;在25℃下,以Langmuir方程和Freundlich方程分别对GFH吸附NO3--N的等温线进行拟合,拟合效果以Langmuir方程较好,相关性达到0.9930。GFH吸附NO3--N的过程符合拟二级动力学方程,初始时刻的吸附速率h在35℃时最大,为1.653 mg/(g.mg),吸附速率常数随温度的升高而增大;吸附反应的活化能Ea为54.72 kJ/mol。本研究结果表明,GFH在饮用水脱氮和含氮浓度较低的污水再生回用领域有实际应用的潜力。Influencing factors,adsorption isotherm and adsorption kinetics of the absorption of nitrate by granular ferric hydroxide（GFH） were studied using simulated nitrate wastewater.Experimental results indicate that adsorption equilibrium of nitrate is achieved within 80min,the removal efficiency of NO-3-N decreases with increasing initial NO-3-N concentration.The pH value at 5 favors the maximum adsorption capacity of NO-3-N and adsorption capacity decreases at higher or lower pH value.Absorption of nitrate on GFH at 25℃ could be described more exactly by Langmuir equation（R2=0.9930） than by Freundlich equation.The adsorption process follows the pseudo-second-order equation with the maximum initial adsorption rate（h） being 1.653 mg/（g·mg） at 35℃,and the adsorption rate constant increases with increasing temperature.The activation energy（Ea） for the absorption reaction is 54.72 kJ/mol.Results of the present study suggest that GFH has the potential ability for NO-3-N removal from drinking water and regeneration of wastewater with low NO-3-N concentration.

关 键 词：粒状羟基氧化铁 硝酸盐 吸附等温线 动力学 

分 类 号：X703.1[环境科学与工程—环境工程]