Removal of arsenic(III) from aqueous solution by concrete‐based adsorbents

Abstract

The present paper investigates the adsorption of arsenic(III) (As(III)) onto 2 concrete‐based low‐cost materials, i.e., Aerocrete and Vermiculite impregnated by ferric oxyhydroxide. Adsorption experiments were performed to study the effect of initial pH, initial concentration of As(III), contact time, and ions usually present in water. No significant effect of the initial pH on the adsorption of As(III) by Aerocrete and Vermiculite was observed at the pH range of 4–8. The As(III) removal efficiency decreased at a high initial pH (i.e., 10). The Langmuir isotherm showed that the maximum As(III) adsorption capacity of Aerocrete and Vermiculite is 15.15 and 13.51 mg/g, respectively, which is higher than that observed using titanium dioxide (i.e., 3.52 mg/g), at pH 7 and 24 ±1 °C. A pseudo‐second order kinetic model fitted well the experimentally obtained kinetic data. This suggests that chemisorption most probably controls the adsorption of As(III) on Aeroctere and Vermiculite. Significantly, As(III) (1 mg/L) could be removed almost completely by both Aeroctere and Vermiculite (1 g/L) in 30 and 60 min, respectively at pH 7 and 24 ±1 °C. Importantly, Ca2+, Mg2+, Na+, HCO3−, SO42−, and Cl− ions had no significant effect on the adsorption of As(III) on Aeroctere and Vermiculite. The results showed that the proposed concrete‐based adsorbents have the potential to remove As(III) from water.

Effective Adsorption of Reactive Black 5 onto Hybrid Hexadecylamine Impregnated Chitosan-Powdered Activated Carbon Beads

“…Furthermore, the calculated adsorption capacity by the PSO model (260.12 mg/g) fits well with the experimental adsorption capacity (256.01 mg/g). These results suggest that adsorption of RB5 onto the Ct-PAC-HDA beads is mainly controlled by chemisorption [37].…”

“…Furthermore, the calculated adsorption capacity by the PSO model (260.12 mg/g) fits well with the experimental adsorption capacity (256.01 mg/g). These results suggest that adsorption of RB5 onto the Ct-PAC-HDA beads is mainly controlled by chemisorption [37]. For investigating suitable conditions for the optimized application of the prepared adsorbent, as well as the study of the nature of RB5 adsorption on Ct-PAC-HDA beads, adsorption equilibrium results were fitted by Langmuir and Freundlich isotherm models (Figure 7).…”

Prediction of arsenic removal in aqueous solutions with non‐neural network algorithms

“…The ranges of different statistical parameters for previous ANN algorithm-and analytical isotherm-based models are 99.994 > R 2 > 80.5, 4.289 > RMSE >0.25, and 14.166 > MAE > 0.001. [11,15,16,18,21,25,29,[43][44][45]47,48] The comparative results for the current models are 99.3 > R 2 > 82.0, 5.1 > RMSE >1.3, and 2.8 > MAE > 0.3 (Table 3), that is, the non-NN models presented here are competent of predicting the capability of an adsorbent to adsorb As, with reasonable accuracy. Furthermore, both SVR and RF models have the advantage of requiring comparatively less preprocessing accompanied by a simpler training process that involves optimizing a fixed number of parameters.…”

“…However, the effectiveness of these technologies depends on the physical and chemical characteristics of As compounds present in the water. Examples of As removal processes include coagulationfiltration, [9][10][11][12][13] membrane separation, [14] adsorption, [5,[15][16][17][18][19] electrolysis, [20] and oxidation. [21] Among these methods, adsorption is probably the most effective technique.…”

L-Histidine immobilized montmorillonite for As(III) adsorption and statistical verification of data by PDF, AICcorrected and AADR models

“…The permissible level of As(III) in drinking water is 5 × 10 -5 to 1 × 10 -5 g.L −1 according to recommendation of World Health Organization (WHO) (Basha, Selvi et al 2009). The presence of As(III) above this limit causes serious health issues like skin and lung cancers, anemia, keratosis, hyperpigmentation, liver fibroses and neurological disorders (Mondal et al 2020).…”