Efficient removal of malachite green dye using biodegradable graft copolymer derived from amylopectin and poly(acrylic acid)

•AP-g-PAA adsorbent exhibits excellent MG adsorption capacity.•The adsorption efficiency depends highly on pzc of adsorbent.•Adsorption capacity of AP-g-PAA is higher than that of various reported adsorbents.•AP-g-PAA demonstrates excellent recyclability. This article reports on the application of a high performance biodegradable adsorbent based on amylopectin and poly(acrylic acid) (AP-g-PAA) for removal of toxic malachite green dye (MG) from aqueous solution. The graft copolymer has been synthesized and characterized using various techniques including FTIR, GPC, SEM and XRD analyses. Biodegradation study suggests that the co-polymer is biodegradable in nature. The adsorbent shows excellent potential (Qmax, 352.11mgg−1; 99.05% of MG has been removed within 30min) for removal of MG from aqueous solution. It has been observed that point to zero charge (pzc) of graft copolymer plays significant role in adsorption efficacy. The adsorption kinetics and isotherm follow pseudo-second order and Langmuir isotherm models, respectively. Thermodynamics parameters suggest that the process of dye uptake is spontaneous. Finally desorption study shows excellent regeneration efficiency of adsorbent.