Use of desalination plant brine activated bamboo stalks as a novel biosorbent to dyestuff removal

This study aims to prepare a chemically activated bamboo stalk (CAB) adsorbent with desalination plant brine and investigate its performance to remove methylene blue (MB) from aqueous solution, in batch and dynamic systems. The (CAB) structural and morphological characterization was studied by SEM–EDS and Wavelength Dispersive X-ray Fluorescence spectrometry. Biosorbent functional groups were identified by analysis (FTIR). The CAB zero charge point (pH PZC ) was determined to be 6.60. The effects of solution pH, initial MB concentration, and adsorbent dose on MB biosorption were examined in batch reactor. At neutral pH, the maximum adsorption capacity (qe) is 15.3 mg g −1 , and the maximum removal is obtained with 5.00 g L −1 of CAB. At MB adsorption equilibrium, changing temperature had no significant impact. The experimental data fit the pseudo-second-order kinetic model perfectly ( R 2 > 0.965). The diffusion phenomena have been analyzed by the Weber-Morris model. The nonlinear regression method using error functions ( R 2 adjust , EABS, χ 2, HYBRID) revealed that Sips model was the best compared to Langmuir, Freundlich, Temkin, Toth, and Redich-Peterson, with values of R 2 adjust = 0.968, EABS = 3.470, χ 2 = 0.297, HYBRID = 15.4. According to thermodynamic results, MB adsorption is exothermic and spontaneous. Fixed-bed column adsorption was most effective at low feed rate (1.0 mL min −1 ), high CAB bed height (13.5 cm), and low MB concentration (20.0 mg L −1 ). The respective performance parameter values are 840 min for throughput time, 3135 min for exhaustion time, and 70.9% for MB removal. The Thomas and Yoon-Nelson models fitted the experimental data very well, with ( R 2 adjust > 0.940).