I investigated the mechanism of highly efficient trace Cr(VI) removal by weak base anion exchange resin called Duolite A7. The results revealed that in addition to ion exchange, redox reactions were also taking place inside the resin, where Cr(VI) oxidised the amine functional groups as well as the phenol-formaldehyde matrix, while itself getting reduced to Cr(III). Cr(III) formed was either precipitated as Cr(OH)3 or formed complexes with carboxylic acid groups formed upon oxidation inside the resin. Byproduct analysis showed that formaldehyde, a human carcinogen, is released in the effluent due to oxidative attack of Cr(VI) on the resin. An attempt was also made to have a more insightful investigation of the adsorption-coupled redox reaction mechanism of Cr(VI) with a lignocellulosic material, coconut husk, since elucidation of the mechanism would help open a new paradigm for designing special class of Cr selective redox-active sorbents.