Boddu Veera M, Abburi Krishnaiah, Talbott Jonathan L, Smith Edgar D, Haasch Richard
Environmental Processes Branch, US Army Engineer Research and Development Center, Construction Engineering Research Laboratory, Champaign, IL 61826-9005, USA.
Water Res. 2008 Feb;42(3):633-42. doi: 10.1016/j.watres.2007.08.014. Epub 2007 Aug 19.
A biosorbent was prepared by coating ceramic alumina with the natural biopolymer, chitosan, using a dip-coating process. Removal of arsenic (III) (As(III)) and arsenic (V) (As(V)) was studied through adsorption on the biosorbent at pH 4.0 under equilibrium and dynamic conditions. The equilibrium adsorption data were fitted to Langmuir, Freundlich, and Redlich-Peterson adsorption models, and the model parameters were evaluated. All three models represented the experimental data well. The monolayer adsorption capacity of the sorbent, as obtained from the Langmuir isotherm, is 56.50 and 96.46 mg/g of chitosan for As(III) and As(V), respectively. The difference in adsorption capacity for As(III) and As(V) was explained on the basis of speciation of arsenic at pH 4.0. Column adsorption results indicated that no arsenic was found in the effluent solution up to about 40 and 120 bed volumes of As(III) and As(V), respectively. Sodium hydroxide solution (0.1M) was found to be capable of regenerating the column bed.
采用浸涂工艺，用天然生物聚合物壳聚糖包覆陶瓷氧化铝制备了一种生物吸附剂。通过在pH 4.0的平衡和动态条件下，在该生物吸附剂上进行吸附，研究了砷（III）（As(III)）和砷（V）（As(V)）的去除情况。将平衡吸附数据拟合到朗缪尔、弗伦德利希和雷德利希-彼得森吸附模型，并对模型参数进行了评估。所有这三个模型都能很好地表示实验数据。根据朗缪尔等温线，该吸附剂对As(III)和As(V)的单层吸附容量分别为56.50和96.46 mg/g壳聚糖。基于pH 4.0时砷的形态，解释了As(III)和As(V)吸附容量的差异。柱吸附结果表明，分别在约40和120个床体积的As(III)和As(V)之前，流出液中未发现砷。发现氢氧化钠溶液（0.1M）能够再生柱床。
