[Research on low-level Hg(II) removal from water by the heavy metal capturing agent]

Huan Jing Ke Xue. 2013 Sep;34(9):3486-92.
[Article in Chinese]

Abstract

Treatment of mercury containing wastewater using conventional approach is considered to be difficult to bring down its concentration to meet the discharge standard. In this study, we utilized dithiocarbamate (DTCR-2), 2,4,6-trimercaptotriazine(TMT-18B), Na2S and Ca(OH)2+ as the advanced treatment agents to remove low-level Hg2+ from water. Due to its better treatment effect, DTCR-2 was finally chosen as the most ideal option. The influence of pH value, dosage of DTCR-2, reaction time, initial Hg2+ concentration as well as other heavy metal ions on the Hg2+ removal were studied. The results showed that DTCR-2 had high removal efficiency under the following conditions: 100 microg x L(-1) of initial Hg2+ concentration, pH 8.0, 1.0 times stoichiometric ratio of DTCR-2 dosage and 10 min of reaction time, leading to 41.36 microg x L(-1) of residual Hg2+ concentration which was below the national discharge standard (50 microg x L(-1)). Moreover, three heavy metal ions including Cd2+, Pb2+ and Cu2+, inhibited the DTCR-2 capturing capacity towards Hg2+ and the inhibition effects followed this order: Cu2+ > Pb2+ > Cd2+, while Zn2+ promoted the Hg2+ removal. From this study, we could provide theoretical support for process design to deal with wastewater containing low mercury concentration using DTCR-2.

MeSH terms

  • Calcium Hydroxide / chemistry
  • Mercury / analysis*
  • Metals, Heavy / analysis
  • Sulfhydryl Compounds / chemistry
  • Triazines / chemistry
  • Water / chemistry
  • Water Pollutants / analysis*
  • Water Purification / methods*

Substances

  • Metals, Heavy
  • Sulfhydryl Compounds
  • Triazines
  • Water Pollutants
  • Water
  • Mercury
  • 2,4,6-trimercaptotriazine
  • Calcium Hydroxide