Use of Pyrolysed Almond and Walnut Shells (PAS and PWS) for the Adsorption of Cationic Dye: Reusing Agro-Waste for Sustainable Development

Authors : Gül KAYKIOĞLU, Nesli AYDIN

Pages : 261-269

Doi:10.18466/cbayarfbe.1310461

View : 60 | Download : 51

Publication Date : 2023-09-30

Article Type : Research Paper

Abstract :Agro-wastes are recognised as a carbon-rich source, which can be converted into value-added products in sustainable development. In this study, the effect of pH, contact time, initial concentration, and ionic strength were evaluated in Methylene Blue insert ignore into journalissuearticles values(MB); adsorption by using an activated carbon obtained from pyrolysed almond insert ignore into journalissuearticles values(PAS); and walnut shells insert ignore into journalissuearticles values(PWS);. The characterisation of PAS and PWS was conducted by SEM-EDX, FT-IR and BET analysis. The removal efficiency of 6 mg/L initial MB concentration improved from 10.6% to 50.42% for PAS, when the adsorbent dose was increased from 0.5 g to 3.5 g in 1 L dye solution. It also improved from 14.8% to 48.7% for PWS, when the adsorbent dose was increased from 0.5 g to 3.5 g. The adsorption fits well with the Freundlich isotherm model and the second-order kinetic model is more favourable. In the adsorption experiments using PWS, 48% removal efficiency was obtained in the absence of NaCl. Depending on the increasing NaCl concentration, the removal efficiencies showed a decrease. 36% removal efficiency was obtained for PWS when 2500 mg/L NaCl was used. In the adsorption experiments using PAS, 40% removal efficiency was obtained in the absence of NaCl. When 500 mg/L NaCl was used, the maximum removal efficiency improved to 48%. However, with the increase in ionic strength, removal efficiencies decreased to approximately 39%. This study revealed that PAS and PWS could be used effectively instead of commercial activated carbon, which also provides an advantageous option from an economic point of view.
Keywords : Adsorption, Agro Waste, Methylene Blue, Removal Efficiency, Sustainable Development