Title :
Effects of dissolved humic acid on ammonium sorption to natural chinese clinoptilolite
Author :
Zhang, Ying ; Bi, Erping
Author_Institution :
Sch. of Water Resources & Environ., China Univ. of Geosci., Beijing, China
Abstract :
Sorption of ammonium (NH4+) to natural clinoptilolite has been paid lot of attention. However, the effect of dissolved humic acid (DHA) on the sorption processes has not been reported in detail. In this study, the effect of the natural clinoptilolite dose, initial NH4+ concentrations, and different DHA concentrations on the sorption was investigated systemically. The sorption kinetics of NH4+ on the natural clinoptilolite could be described by the pseudo-second-order kinetic model both in NH4+ and NH4++DHA systems. Equilibrium sorption data in both systems were fitted by the Langmuir model. The maximum sorption capacities of NH4+ in NH4+ and NH4++DHA systems were 10.53 mg/g and 10.83 mg/g, respectively. A decrease of NH4+ removal efficiency could be seen with the increase of DHA concentration, and this phenomenon was more obvious when the initial NH4+ concentration was low. The negative effect of DHA on the removal of NH4+ was probably due to the competition between DHA and NH4+, and the surface coverage of the clinoptilolite by DHA.
Keywords :
geochemistry; sorption; zeolites; DHA concentrations; Langmuir model; NH4+ removal efficiency; NH4++DHA systems; ammonium sorption; dissolved humic acid; initial NH4+ concentrations; maximum sorption capacities; natural Chinese clinoptilolite; natural clinoptilolite dose; pseudosecond-order kinetic model; sorption kinetics; sorption processes; surface coverage; Chemicals; Data models; Hazardous materials; Kinetic theory; Mathematical model; Oxidation; Water pollution; Dissolved Humic Acid (DHA); Natural Clinoptilolite; Sorption of Ammonium;
Conference_Titel :
Water Resource and Environmental Protection (ISWREP), 2011 International Symposium on
Conference_Location :
Xi´an
Print_ISBN :
978-1-61284-339-1
DOI :
10.1109/ISWREP.2011.5893173
