Adsorption of As (III) and As (V) from aqueous solution by modified Cassia fistula (golden shower) biochar

Abstract

The biosorption of two Arsenic (As) species [As (III) and As (V)] from aqueous solution onto activated biochar derived from Cassia fistula, belonging to Fabaceae family was studied. SEM/EDX characterization of the adsorbent showed an irregular, porous, and heterogeneous surface morphology with calcium and iron available for As binding. FTIR also showed the presence of groups responsible for As adsorption. Batch adsorption experiments were conducted to determine the optimum conditions for As adsorption to the biomass with optimum adsorbent dose, ambient temperature, initial concentration of As, pH, and stirring rate. Under optimized conditions, the maximum removal percentage was 78.1% [uptake capacity (q e) = 0.78 mg/g] for As (III) and 84.8% [uptake capacity (q e) = 0.42 mg/g] for As (V). The Freundlich isotherm model, characteristic of multilayer binding, fit the data best with R 2 values of 0.92 for As (III) and 0.96 for As (V). Fitting of the data to the Dubinin-Radushkevich model indicated physisorption, while the kinetics study suggested a pseudo-second-order reaction. Thermodynamic parameters indicated adsorption was spontaneous. In aqueous solutions, phosphate hindered As removal more than the any other ions. Regeneration studies showed a 23.0% and 21.1% recovery for arsenite and arsenate, respectively, indicating limited leaching under both acidic and alkaline conditions. The absorptive capacity of C. fistula biomass for arsenic removal was compared with a number of other reported biosorbents and was found to be considerably efficient.

Enhanced simultaneous adsorption of As(iii), Cd(ii), Pb(ii) and Cr(vi) ions from aqueous solution using cassava root husk-derived biochar loaded with ZnO nanoparticles

“…While for CRHB-ZnO3, these values were 17.41 mg g À1 , 29.62 mg g À1 , 31.73 mg g À1 , 14.20 mg g À1 , respectively. This conclusion was relatively similar in comparison to the study of Alam et al 42 who concluded an optimal time of 50 min for As(III) adsorption by golden shower biochar, and the study of Kołodyńska et al 69 who shared the same trend of optimal reaction time for adsorption of Cu(II), Zn(II), Cd(II) and Pb(II) onto pig and cow manure biochar.…”

Determination of Suitable Extractant for Estimating Plant Available Arsenic in Relation to Soil Properties and Predictability by Solubility-FIAM

“…Water Air Soil Pollut (2021) 232:247 of using soils of diverse properties for experimentation as reported by Giri et al (2012). (Alam et al, 2018). The next efficient extractant was 0.5 (M) NaHCO 3 , 772.7 ± 81.63 µg kg −1 , followed by 0.5 (N) NH 4 F, 539.8 ± 65.66 µg kg −1 .…”

Cadmium Removal from Synthetic Wastewater using Seed Biomass Biosorbent: A Bench-top Reactor Investigation

“…We observed the maximum cadmium removal ~95% for JP and 93% for AT at adsorbent dose 60mg. After the dose of 0.185mg/L for JP and 0.215 mg/L for AT, it attained equilibrium and further addition did not change in the percentage of adsorption.In the experiments of Alam et al (2018) increased biochar dose of modified Cassia fistula from 1 to 8 gL −1 , was able to remove about 74.5% cadmium from synthetic wastewaterafter in batch experiments at dose up to 6 gL −1 . The dependence of cadmium removal on the amount of adsorbent was investigated at pH of 6 using 50 ml cadmium solution at 28℃ for 70 min in the range of 0.05-0.215mg/L adsorbent dosage.…”

“…The seed bio-sorbents used in present study have maximum adsorption capacity 3.88 mg g −1 for JP and 4.54 mg g −1 for AT in 70 min. Earlier modified biochar of Amaltash (AT) with Fe / Mn impregnation showed adsorption capacity 0.75 mg g −1 at room temperature by Alam et al (2018). Alkurdi and coworkers (2019) reported that pyrolysed pinewood biochar sorption capacity around 0.50 mg g −1 .…”