Synthesis and Characterization of Chelating Resins Containing Thiol Groups
Park IH, Bang YK, Kim KM, Joo HJ
티올기를 함유하는 킬레이트 수지의 합성 및 특성
박인환, 방영길, 김경만, 주혁종
Abstract
Three kinds of macro-reticular bead-typed chelating resins having thiol groups were obtained from basic resins like poly(styrene-co-divinylbenzene) (PSD) and poly(styrene-co-methyl methacrylate-co-divinylbenzene) (PSMD): the chelating resin (I) was prepared by chloromethylation of phenyl rings of PSD followed by thiolation using thiourea. The chelating resins (II) was designed to provide enough space to chelate heavy metal ions; one chloromethyl group was obtained by chlorination of hydroxymethyl group provided by reduction of carboxylic ester group of PSMD and another chloromethyl group was obtained by direct chloro-methylation of pendent phenyl group using chloromethyl methyl ether. Both of chloromethyl groups were thiolated by using thiourea. The chelating resin (III) was prepared by chlorosulfonation of phenyl rings of PSD followed by thiolation using sodium hydrosulfide. The adsorbtivity toward heavy metal ions was evaluated. The hydrophobic chelating resin (I) with thiol groups showed highly selective adsorption capacity for mercury ions. However, the chelating resin (II) with thiol groups showed more effective adsorption capacity toward mercury ions than chelating resin (I) with thiol groups, and showed some adsorption capacity for other heavy metal ions like Cu2+, Pb2+, Cd2+ and Cr3+. On the other hand, the chelating resin (III) which have hydrophilic thiosulfonic acid groups was found to be effective adsorbents for some heavy metal ions such as Hg2+, Cu2+, Ni2+, Co2+, Cr3+ and especially Cd2+ and Pb2+.
폴리(스티렌-co-디비닐벤젠) 수지 페닐고리의 클로로메틸화를 통해 메틸렌티올기를 도입한 수지 (I), 폴리(스티렌-co-메틸 메타아크릴레이트-co-디비닐벤젠) 공중합체의 페닐고리와 에스터기에 클로로메틸화 반응을 거쳐 각각 메틸렌티올기를 도입하여 중금속 이온들과의 배위결합에 필요한 공간개념을 배려한 수지(II)및 폴리(스티렌-co-디비닐벤젠) 수지의 페닐고리를 클로로설폰화한 후, 소디움하이드로술파이드로 티오설폰산화한 수지(III) 등 3가지 종류의 티올계 구상형 수지들을 합성하였다. 이어, 이들 킬레이트 수지들에 대한 중금속 이온의 흡착경향을 평가한 결과, 티올기 함유 I형 킬레이트 수지는 Hg2+에 대해서만 선택적 흡착성을 보였고, 티올기 함유 II형 킬레이트 수지는 Hg2+에 대한 흡착성능이 보다 향상되었으며, Cu2+, Pb2+, Cd2+및 Cr3+등의 몇몇 중금속 이온들에 대해서도 약간의 흡착능을 보였다. 다른 한편으로, 친수성의 티오설폰산기 함유 III형 킬레이트 수지는 효율적 흡착체로서 Hg2+, Cu2+, Ni2+, Co2+ 및 Cr3+등의 중금속 이온들은 물론, 특히 Cd2+및 Pb2+에 높은 흡착능을 보였다.
Keywords: chelating resin; thiol group; poly(styrene-co-divinylbenzene); poly(styrene-co-methyl methacrylate-co-divinylbenzene); heavy metal ions