ABSTRACT
INTRODUCTION E xcess co n cen tra tio n s o f m ercu ry in w as te w a te rs have alw ays p ro v en to
b e an im m inent h aza rd to hum an hea lth and th e env ironm ent. A d so rp tio n te ch n o lo g y h as been exam ined by several research ers fo r rem oval o f m ercu ry fro m w astew ate r . M a et al.{ 1992) eva lu a ted th e so rp tio n o f m ercu ry w ith F S -4 0 0 , a g ran u la r ac tiv a ted carbon , and o b se rv ed th a t so lu tion p H 7 p rov ided g o o d resu lts fo r m ercu ry ad so rp tio n . R itte r et al. (1 9 9 2 ) exam ined an ion ex c h an g e resin, D u o lite G T 7 3 , fo r rem oval o f m ercu ry from an industrial w astew ate r . T h eir s tudy sh o w ed th a t th e ion ex ch an g e facility requ ired h igh co n tac t tim e and lo w flow ra te to red u c e m ercu ry co n cen tra tio n s to less th an 10pg/l. T h eir s tu d y also sh o w ed th a t th e o p era tin g cap ac ity o f th e ad so rb en t fo r m ercu ry rem oval w as m uch lo w er th an th a t specified by th e m anufactu rer. It w as su g g ested th a t th e lo w er cap ac ity w as p robab ly d u e to th e p resen ce o f o th e r species in th e w as tew a te r th a t m ay have o x id ized th e th io l functional g ro u p s and ren d ered them inactive, as w ell as th e high o rgan ic co n ten t in th e w as tew a te r m ay have b een fou ling th e resin by b lo ck in g th e p o res. H elm ig ( 1995) o f W yeth -A y erst L ab o ra to rie s , investiga ted th e u se o f resins hav ing th io l, iso th iou ron ium , im inod iacetic acid and ca rb am ate functio n alities as w ell as m a c ro p o ro u s resin and g ran u la r ac tiv a ted ca rb o n as ad o rb en ts fo r u se in rem o v in g o rg an ic and ino rgan ic m ercu ry species from pharm aceu tica l p ro ce ss w astew ate rs . T h e resu lts o f th is w o rk a re d esc rib ed in U. S. P a te n t 5 ,4 3 7 .7 9 7 , A u g u st 1, 1995 “M ercu ry R em oval F ro m W a ste w a te r” . T h e p a ten t describ es a p ro ce ss fo r rem o v in g o rg an ic and ino rgan ic m ercu ry sp ecies fro m v accine p ro d u c tio n w as tew a te rs using m a c ro p o ro u s c ro ss linked p o lysty rene resins hav ing p o ly iso th io u ro n iu m functional g ro u p s. A series o f p re trea tm e n t s tep s involving ac id ification w ith HC1, filtra tio n to rem o v e solids, and ca rb o n ad so rp tio n to rem o v e ch lo rin e and o rg an ics are d escribed in th e paten t. T h ese p re trea tm e n t s tep s w e re d ev e lo p ed to p rev en t resin fou ling and m axim ize bed capacity .
