期刊
WATER
卷 14, 期 6, 页码 -出版社
MDPI
DOI: 10.3390/w14060987
关键词
selenium; organoselenium; selenomethionine; selenocysteine; nanocomposite-nZVI; GAC; adsorption kinetics; wastewater treatment; isotherm studies
资金
- Natural Sciences and Engineering Research Council of Canada (NSERC)
This study investigated the removal of organoselenium from wastewater using nanoscale zerovalent iron particles immobilized on coconut shell-based granular activated carbon. The results showed that the composite adsorbent had a strong affinity for adsorbing selenomethionine and selenocysteine, with removal efficiencies of 78.2% and 99.9% respectively. Kinetic and isotherm models supported the efficient adsorption of the organoselenium by the composite adsorbent.
Nanoscale zerovalent iron particles (nZVI) immobilized on coconut shell-based granular activated carbon (GAC) were studied to remove organoselenium from wastewater. A chemical reduction technique that involves the application of sodium borohydride was adopted for the adsorbent preparation. The texture, morphology and chemical composition of the synthesized adsorbents were analyzed with a scanning electron microscope (SEM), nitrogen adsorption-desorption isotherms and X-ray diffraction (XRD). Batch experiment with various pHs and contact times were conducted to evaluate nZVI/GAC adsorption performance. The results showed that nZVI/GAC has a strong affinity to adsorb selenomethionine (SeMet) and selenocysteine (SeCys) from wastewaters. The maximum removal efficiency for the composite (nZVI/GAC) was 99.9% for SeCys and 78.2% for SeMet removal, which was significantly higher than that of nZVI (SeCy, 59.2%; SeMet, 10.8%). The adsorption kinetics were studied by pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models. Amongst the two, PSO seemed to have a better fit (SeCy, R-2 > 0.998; SeMet, R-2 > 0.999). The adsorption process was investigated using Langmuir and Freundlich isotherm models. Electrostatic attraction played a significant role in the removal of organoselenium by nZVI/GAC adsorption. Overall, the results indicated that GAC-supported nZVI can be considered a promising and efficient technology for removing organoselenium from wastewater.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据