title: Biosorption of aquatic cadmium(II) by unmodified rice straw.
abstract: Cadmium is the most common toxic metal threatening safe rice supply. Rice straw has the potential to remove Cd from large-scale effluent contaminated by heavy metals since it exhibited a short biosorption equilibrium time of 5 min, high biosorption capacity (13.9 mg g(-1)) and high removal efficiency at a pH range of 2.0-6.0. The main Cd biosorption mechanism was Cd(2+) ion exchange with K(+), Na(+), Mg(2+) and Ca(2+), together with chelation with functional groups such as C=C, CO, OH and carboxylic acids. When 0.5% (w/v) rice straw was exposed to 50 mg mL(-1) CdSO(4) solution with shaking at 150 r min(-1) for 3h, about 80% of the aquatic Cd was absorbed and the Cd content in rice straw reached 8-10 mg g(-1), suggesting that the metal-enriched rice straw could become high quality bio-ore by virtue of the industrial mining grade of its metal content and easy metal recovery.
authors.affiliation: College of Life Sciences, Capital Normal University, Beijing 100048, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Ding
authors.forename: Debing
authors.initials: D
authors.lastname: Jing
authors.forename: Huili
authors.initials: H
authors.lastname: Gong
authors.forename: Lianbi
authors.initials: L
authors.lastname: Zhou
authors.forename: Xiaosong
authors.initials: X
authors.lastname: Yang
mesh_terms: D000042:Absorption; D002104:Cadmium / Q000737:chemistry / Q000302:isolation & purification*; D003198:Computer Simulation; D008956:Models, Chemical; D012275:Oryza / Q000737:chemistry*; D035261:Plant Components, Aerial / Q000737:chemistry*; D014462:Ultrafiltration / Q000379:methods*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D014874:Water Pollutants, Chemical; D002104:Cadmium; D014867:Water