Polyacrylate/kaolin hydrogel composite was prepared via ultrasonic irradiation using various crosslinking agent contents (N, N'-Methylenebisacrylamide (MBA)) and characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and Brunauer Emmett and Teller (BET) method. Moreover, heavy metals adsorption was investigated using synthetic solutions and industrial wastewater (single and mixed elements) in both lab-scale batch and pilot-scale continuous modes. Results indicated that 0.3 wt% MBA is the optimum content regarding structure, swelling behavior and single element batch adsorption results. Batch tests revealed adsorption capacities of 75, 33, 38 and 96 mg/g for Cr, Co, Ni and Pb, respectively from mixed solutions. It is inferred that mixed synthetic solutions and industrial wastewater have lower adsorption capacities than single solutions, where Pb attained the highest performance. Pilot-scale continuous adsorption for mixed synthetic solutions in a fluidized bed column revealed that 24 h cycle time is appropriate for Cr and Pb removal while 48 h is optimum for Co and Ni. Sulphuric acid revealed the best desorption efficiencies which lie in the order of Co > Ni >Pb >>Cr. According to these results, the developed hydrogel composite is reliable for heavy metals uptake under different adsorption modes.