Accumulation of vanadium and arsenic by cast iron pipe scales under drinking water conditions: A batch study.
Accumulation of vanadium and arsenic by cast iron pipe scales under drinking water conditions: A batch study.
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DOI：
10.1016/j.chemosphere.2020.129396
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发表时间：
2020-12
期刊：
影响因子：
8.8
通讯作者：
N. He;Yi-mei Tian;Chuntong Liu;Weigao Zhao;Ran Liu;Jianjun Huang
中科院分区：
文献类型：
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作者：
N. He;Yi-mei Tian;Chuntong Liu;Weigao Zhao;Ran Liu;Jianjun Huang
金属污染物在给水管网中的累积对水质构成潜在威胁。为此，对铸铁管垢对V（V）和As（V）的富集作用进行了研究。研究了结垢对V（V）和As（V）的富集作用，以及结垢投加量、pH、温度和阴离子含量对富集过程的影响。结果表明，鳞片对V（V）和As（V）具有快速富集作用，最大富集量分别为3.94mg/g和3.90mg/g; pH值（从3.0到9.0）和硫酸盐浓度（从0到250 mg/L）的增加降低了结垢对V（V）和As（V）的积累。随着Cl ~-浓度的增加（0 ~ 250 mg/L），As（V）的积累量减少，V（V）的积累量增加。V（V）和As（V）的富集动力学可用Elovich模型描述，热力学和富集等温线表明富集过程是通过熵吸热反应进行的。结垢对V（V）和As（V）的富集机制包括表面络合、配体交换、静电吸引和排斥以及竞争吸附。
Metal pollutants accumulation in the scales of drinking water distribution systems presents a potential threat to water quality. Therefore, a study was carried out on the accumulation of V(V) and As(V) by cast iron pipe scales. The accumulation of V(V) and As(V) by scales and the effects of scale dosage, pH, temperature, and anion content on the accumulation process were assessed. Results showed that scales could rapidly accumulate V(V) and As(V), with maximum accumulation amounts of 3.94 mg/g and 3.90 mg/g, respectively. An increase in pH (from 3.0 to 9.0) and sulfate concentration (from 0 to 250 mg/L) decreased V(V) and As(V) accumulation by scales. Increased chloride ion concentrations (from 0 to 250 mg/L) reduced the amount of As(V) accumulated, while increasing the amount of V(V) accumulated. The V(V) and As(V) accumulation kinetics were well described by the Elovich model, with thermodynamic and accumulation isotherms showing that the accumulation process occurred via an entropic endothermic reaction. The mechanisms of accumulation of V(V) and As(V) by the scales include surface complexation, ligand exchange, electrostatic attraction and repulsion, and competitive adsorption.