The primary objective of this research was to assess the potential of magnetic bleached biochar(MBBC)as a cost-effective adsorbent for arsenic removal.To achieve this,locally collected tea wastes underwent meticulous cleaning,bleaching,and modifications via thermal and chemical treatments.Both non-magnetic and magnetic biochar adsorbents were thoroughly characterized using Fourier transform-infrared spectroscopy(FT-IR)and thermo-gravimetric analysis(TGA).Subsequently,the adsorptive performance of MBBC in removing arsenic from wastewater samples was investigated,considering various crucial parameters such as adsorbent-adsorbate contact time,concentration of As,temperature,adsorbent dosage,and the regeneration-ability of the adsorbent.The experimental data for the adsorption process were best represented by the Langmuir isotherm,indicating its suitability for the MBBC adsorbent.Remarkably,the MBBC demonstrated a maximum Langmuir adsorption capacity of approximately 714 mg/g at room temperature,highlighting its efficiency as an arsenic adsorbent.Furthermore,the Lagergren's Pseudo-second order kinetic model proved to be the most suitable for describing the adsorption kinetics,confirming the chemisorption nature of the process.The results also indicated that the adsorption process is endothermic and feasible,suggesting its viability for practical applications.Taking all findings into account,the comprehensive analysis strongly supports the potential use of MBBC as a highly promising and cost-effective adsorbent for efficiently removing arsenic from aqueous samples.This research contributes valuable insights to the field of wastewater treatment and offers a sustainable and environmentally friendly solution for tackling arsenic contamination in water sources.
Activated carbon(AC)was synthesized from palm kernel shell(PKS)using different activating agents,i.e.,steam,carbon dioxide(CO 2),and CO 2-steam,in order to analyze the impact of acti-vating agents on the pore opening of AC.In this study,AC produced from PKS was found to have great potential as an adsorbent for methane storage.The different molecular diffusivity and reac-tivity of the combination of CO 2 and steam succeeded in producing AC with the highest burn-offof 78.57%,a surface area of 869.82 m 2/g,a total pore volume of 0.47 cm 3/g,and leading to maximum methane gas adsorption capacity of 4.500 mol/kg.All types of ACs exhibited the best fit with the Freundlich isotherm model,with the correlation coefficient(R 2)ranging from 0.997 to 0.999,indicating the formation of multilayer adsorption.In addition,the adsorption kinetic data for all ACs followed the pseudo-first-order model showing that the rate of adsorption was dependent on both the adsorbent and the adsorbate and was governed primarily by physical ad-sorption between the pore surface and methane gas.The results of intraparticle diffusion model indicated that the adsorption of methane was affected by both pore diffusion and exterior layer diffusion due to the different adsorption rates.
Mohd Saufi Md ZainiMuhammad ArshadSyed Shatir A.Syed-Hassan
The main objective of the study is to improve the removal efficiency of Ourlago-kaolin (Kao), sodium montmorillonite (Na-MMT), and two formulated clay-lime (F13 and F23) towards CI Acid Orange 52 dye (AO52). F13 and F23 were obtained by chemical stabilization through thermal treatment at 300°C. Fourier Transform Infrared spectra showed different surface functional groups on the clay materials, X-ray diffraction patterns revealed the raw materials contain many crystalline phases, scanning electron microscopy micrographs showed the variation of the layered structures of different clay materials, energy dispersive X-Ray analysis micrographs revealed compositional information and thermogravimetric-differential scanning calorimetry curves indicated the higher weight loss of 11.26% and 11.38% were observed for F13 and F23 respectively. BET surface area analyzed gave 133.0071 m2•g−1 for F13 and 132.34803 m2•g−1 for F23. The optimum pH value was 2.0 for Kao and Na-MMT. The adsorption experiments indicated that F13 and F23 have the maximum uptake abilities of 7.8740 and 3.1645 mg•g−1, respectively, compared to Kao (0.8761 mg•g−1) and Na-MMT (2.6178 mg•g−1). The pseudo-second-order model well described the adsorption kinetic model of AO52 dye onto the overall samples;Langmuir and Freundlich’s isotherms appropriately described the uptake mechanism. The positive values of ∆G° and negative value ∆H° indicated that the adsorption process was spontaneous and endothermic for Na-MMT, and non-spontaneous and exothermic for Kao, F13, and F23 because of their positive values of ∆G° and negative value of ∆H°. The modified clays have higher adsorption capacities and better life cycles compared hence opening new avenues for efficient wastewater treatment.
Fumba GastonEssomba Jean SergeAnkoro Naphtali OdoguKouotou DaoudaBélibi Bélibi Placide DésiréNdi Julius NsamiKetcha Mbadcam Joseph
