Exploring the Sorption Characteristics of Gum Arabic Grafted Polyacrylamide Hydrogel in Acid Yellow‐34 Contaminated Water

ABSTRACT Rapid industrial progress may ultimately culminate in water contamination with recalcitrant dyes which seriously disrupt aquatic life, humans and natural environment. The underscored risks stemmed from dye contamination was significantly mitigated via facile sorption of acid yellow‐34 (AY‐34) onto gum Arabic grafted polyacrylamide (GA‐g‐pAAm) hydrogel sorbent. The sorbent was facilely fabricated, in single step, through free radical polymerization method. Then detailed sorption tests were systematically performed by exploring the effect of contact time, pH, initial AY‐34 concentration and temperature. The current sorption data essentially followed pseudo second order kinetic and Freundlich isotherm model. The GA‐g‐pAAm sorbent reached maximum sorption capacity (q m ) of 697.67 mg g −1 at 60°C. The positive ∆H° (52.767 kJ/mol) and ∆S° (169.222 J/mol. K) values unequivocally demonstrated the current sorption as endothermic and accompanied with rise in entropy at the liquid/solid interface, respectively. The negative ∆G° (−3.584 kJ mol −1 ) value at 60°C indicates spontaneous sorption of AY‐34 by GA‐g‐pAAm hydrogel. During regeneration, the sorbent maintained promisingly high performance (72.5%) even after fifth regeneration cycle, which highlights promising sustainability of the subject material for the treatment of industrial wastewater in commercial applications.