Static adsorption of 2-nitrochlorobenzene and 2-nitrophenol from wastewater by macroporous resin RD-100

Among the six kinds of macroporous adsorption resin, the RD-100 was screen out with the best adsorption capacity to remove o-nitrochlorobenzene （OCNB） and o-nitrophenol （ONP） from the wastewater of 1-hydroxybenzotriazole producing. The static adsorption kinetics study showed that the adsorption kinetics of the resin RD-100 for OCNB and ONP conformed to the pseudo-first-order model, and the adsorption process conformed to the Freundlich model, that is a multi-molecular layer adsorption. The maximum theoretical adsorption capacities of the resin for OCNB and ONP were 1 087.0 mg·g⁻¹ and 574.7 mg·g⁻¹, respectively. The thermodynamic study indicated that the adsorption of OCNB by the resin RD-100 was an endothermic process while the adsorption of ONP was an exothermic proces and, their adsorption enthalpies were 88.5 kJ·mol⁻¹ and −2.1 kJ·mol⁻¹, respectively. After six cycles of static adsorption and regeneration, the adsorption capacity only decreased by 5.5% （OCNB） and 6.2% （ONP）. For single-component dynamic adsorption, the breakthrough points （C_t/C₀=5%） were 420 min for ONP and 580 min for OCNB. The results suggest that the resin RD-100 can effectively adsorb OCNP and ONP from wastewater.