PREPARATION AND CHARACTERIZATION OF A MERCAPTAN DERIVATIVE OF CHITOSAN FOR THE REMOVAL OF MERCURY FROM BRINES

Chitosan, [(1,4)-2-amino-2-deoxy-beta-D-glucan], was reacted consecuti vely with epi-chlorohydrin and thiourea. Subsequent hydrolysis of the isothiouronium salt yielded the mercaptan derivative of chitosan, whic h scavenges mercury ions from solution in the presence of a considerab ly high concentration of chloride ions. Sulfur contents varied with re acting conditions and reached values up to 7.3%. The derivative is ins oluble due to partial crosslinking of chitosan during the reaction wit h epichlorohydrin and was characterized by IR spectroscopy, solid-stat e C-13 NMR, thermal analysis and pyrolysis-mass spectrometry.