title: Adsorption of Cr(VI) using silica-based adsorbent prepared by radiation-induced grafting.
abstract: Silica-based adsorbent was prepared by radiation-induced grafting of dimethylaminoethyl methacrylate (DMAEMA) onto the silanized silica followed by a protonation process. The FTIR spectra and XPS analysis proved that DMAEMA was grafted successfully onto the silica surface. The resultant adsorbent manifested a high ion exchange capacity (IEC) of ca. 1.30 mmol/g and the Cr(VI) adsorption behavior of the adsorbent was further investigated, revealing the recovery of Cr(VI) increased with the adsorbent feed and the equilibrium adsorption could be achieved within 40 min. The adsorption capacity, strongly depended on the pH of the solution, reached a maximum Cr(VI) uptake (ca. 68 mg/g) as the pH was in the range of 2.5-5.0. Furthermore, even in strong acidic (4.0 mol/L HNO(3)) or alkaline media (pH 11.0), the adsorbent had a sound Cr(VI) uptake capacity (ca. 22 and 30 mg/g, respectively), and the adsorption followed Langmuir mode. The results indicated that this adsorbent, prepared via a convenient approach, is applicable for removing heavy-metal-ion pollutants (e.g. Cr(VI)) from waste waters.
authors.affiliation: Beijing National Laboratory for Molecular Science (BNLMS), Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China. qiujingyi@pku.edu.cn
authors.forename: Jingyi
authors.initials: J
authors.lastname: Qiu
authors.forename: Ziyue
authors.initials: Z
authors.lastname: Wang
authors.forename: Huibo
authors.initials: H
authors.lastname: Li
authors.forename: Ling
authors.initials: L
authors.lastname: Xu
authors.forename: Jing
authors.initials: J
authors.lastname: Peng
authors.forename: Maolin
authors.initials: M
authors.lastname: Zhai
authors.forename: Chao
authors.initials: C
authors.lastname: Yang
authors.forename: Jiuqiang
authors.initials: J
authors.lastname: Li
authors.forename: Genshuan
authors.initials: G
authors.lastname: Wei
mesh_terms: D000327:Adsorption; D002857:Chromium / Q000302:isolation & purification*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000517:prevention & control; D007474:Ion Exchange; D008689:Methacrylates / Q000737:chemistry / Q000528:radiation effects; D055668:Photochemical Processes; D012822:Silicon Dioxide / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
chemical_list: D007220:Industrial Waste; D008689:Methacrylates; D014874:Water Pollutants, Chemical; D002857:Chromium; D012822:Silicon Dioxide; C049840:2-(dimethylamino)ethyl methacrylate