Extraction of Heavy Metals by 2-Mercaptoethoxy Groups Attached to Silica Gel

Abstract

Silica gel is currently being used as a support for various straight chain mono- and bifunctional compounds such as amines, thiols (mercaptans), and mercaptoalochols. The current study reports the results of an investigation of a 2-mercaptoethoxy moiety covalently attached to silica gel. The condensation was effected by acid-catalyzed condensation of toluene solution of 2-mercaptoethanol and silica gel and azeotropically removing the water using a Dean-Stark tube. As a coordinating agent, this bifunctional compound was used in the removal of copper(II), cadmium(II), and lead(II) from standard aqueous solutions. Using silica gel support, the removal percentages were 91–93% for the three metals.

Keywords:

• Mercaptoalcohols
• Cadmium
• Copper
• Lead
• Silica gel
• Azeotropic distillation
• Remediation