Arsenic (V) Remediation Using Adsorption-Induced Ultrafiltration Process and Management of Toxic Sludge in Glass Formation
An integrated approach involving adsorption in combination with ceramic membrane-assisted ultrafiltration (UF) has been used for arsenic remediation from aqueous system. Iron oxide nanoparticles (α-Fe2O3) synthesized by a green route were used as an effective adsorbent for arsenic (V). Ceramic UF membrane was prepared by coating of nano ɣ-Al2O3 on clay–alumina-based substrates with 8 mm OD/6 mm ID/200 mm L. The effect of independent parameters, viz. transmembrane pressure (TMP) and cross-flow velocity (CFV), on the dependent response permeate flux had been studied using response surface methodology (RSM) based statistical optimization employing Design-Expert 6.0.8. A good match is found between experimental and predicted responses with the R2 value being 0.99. The CFV and TMP for maximum permeate flux was 1 m/s and 4 bar, respectively. The combined process resulted in reduction of arsenic (V) concentration up to 97.7% from an initial concentration of 5 mg/L with subsequent removal of turbidity and total suspended solids in the simulated water. The arsenic-bearing toxic sludge produced in the process was immobilized in glass matrix proposing a novel and safe approach of sludge management. Two different glass compositions (G-1 and G-2) having silica and borate as main glass formers doped with different amount of the sludge involving spent iron oxide adsorbent were chosen and their properties were compared. The batches were melted at 1200 °C and 1450 °C for G-1 and G-2, respectively, followed by annealing at 700 °C. The prepared glass samples were found to have an amorphous phase having density of 2.37 g/cc and 2.31 g/cc and refractive index of 1.57 and 1.53, respectively. The amber coloured glasses thus formed could be used in various applications. The proposed study indicates a suitable, environmental friendly approach for efficient remediation of arsenic, a toxic contaminant, from aqueous solution.
The financial support from the Council of Scientific and Industrial Research (CSIR), Government of India, is gratefully acknowledged for completion of this work.
- 2.Gebreyowhannes YB (2009) Effect of silica and pH on arsenic removal by iron-oxide coated sand. MSc Thesis, Unesco-IHEGoogle Scholar
- 6.Sarkar S, Ghosh S, Banerjee P, Larbot A, Cerneaux S, Bandyopadhyay S, Bhattacharjee C (2014) Preparation and characterization of single layer ultrafiltration alumina membrane directly over porous clay-alumina tubular and capillary support for textile effluent treatment. T Indian Ceram Soc. https://doi.org/10.1080/0371750X.2014.882246CrossRefGoogle Scholar
- 8.Mahzuz HMA, Alam R, Alam MN, Basak R, Islam MS (2009) Use of arsenic contaminated sludge in making ornamental bricks. Int J Environ Sci Tech 6:291–298Google Scholar
- 12.Chorfa A, Madjoubi MA, Hamidouche M, Bouras N, Rubio J, Rubio F (2010) Glass hardness and elastic modulus determination by nanoindentation using displacement and energy methods. Ceramics—Silikáty 54:225–234Google Scholar