title: Removal of low concentrations of ammonium and humic acid from simulated groundwater by Vermiculite/Palygorskite mixture.
abstract: Contaminants in water are classified into different types based on their physical and chemical properties. Thus, more than one type of sorbents may be needed for their removal. In this article, a combination of vermiculite with palygorskite was studied for their simultaneous removal of ammonium and humic acid from simulated groundwater. Batch results showed that the Langmuir model described ammonium adsorption well with an adsorption capacity of 22 mg/g while the humic acid adsorption data fitted to the linear adsorption better, suggesting different removal mechanisms of these two types of contaminants. Kinetic studies showed an instantaneous removal of ammonium and humic acid. A column packed with mixture of equal volumes of vermiculite and palygorskite could treat 100 pore volumes for ammonium removal at an initial concentration of 10 mg/L and 500 pore volumes for humic acid removal at an initial concentration of 20 mg/L before the effluent concentrations exceeded the standard.
authors.affiliation: School of Material Sciences and Technology, China University of Geosciences, Beijing, 100083, China.
authors.forename: Xiuli
authors.initials: X
authors.lastname: Zhang
authors.forename: Guocheng
authors.initials: G
authors.lastname: Lv
authors.forename: Libing
authors.initials: L
authors.lastname: Liao
authors.forename: Maoqian
authors.initials: M
authors.lastname: He
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Li
authors.forename: Mingshan
authors.initials: M
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D000538:Aluminum Silicates / Q000737:chemistry*; D060587:Groundwater / Q000737:chemistry*; D006812:Humic Substances / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D017616:Magnesium Compounds / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D017655:Silicon Compounds / Q000737:chemistry*; D013696:Temperature
chemical_list: D000538:Aluminum Silicates; D006812:Humic Substances; D017616:Magnesium Compounds; D000644:Quaternary Ammonium Compounds; D017655:Silicon Compounds; C003760:vermiculite; C026325:attapulgite