Reactive dyes adsorption via Citrus hystrix peel powder and Zea mays cob powder: characterization, isotherm and kinetic studies
Al-Ghamdi, Kevin Beng Kieng Lau 1, Tony Hadibarata 1,*, Elwina Elwina 2 , Ratni Dewi 2, Abdulaziz A. Alsahli 3, Ibrahim A. Alaraidh 3, Abdullah Ahmed . 2020
Adsorption is one of the generally used treatment methods due to the low-cost, high removal effect and simple design The aim of the study was to investigate the adsorption efficiency of lignocellulosic waste such as lime peel (Citrus hystrix) and CC (Zea mays) for removal of Reactive Violet 5 (RV5) and Reactive Red 2 (RR2) dyes. The physical and chemical characteristics of the adsorbents were analyses by using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Additionally, the solution acidity, adsorbent mass, duration of adsorption, and dye concentration were evaluated with isotherm and kinetic study to determine the mechanism of adsorption. The removal of RV5 for lime peel and CC achieved to 50 % and 48 % while the removal of RR2 for lime peel and CC reached 53 % and 46 %. The highest adsorption capacity for both adsorbents was 4.29 mg/g and 6.14 mg/g. In terms of physical characteristics, the adsorbent had large surface area that adsorbs more dyes in same amount of dye concentration. The results showed that Freundlich isotherm and Pseudo-first-order kinetic models were best fitted to the adsorption process with R2 value of 0.9974 and R2 value of 0.9919.
