Color removal from model dye effluent using PVA-GA hydrogel beads. (1st March 2021)

• Record Type: Journal Article
• Authors: Jain, Prarabdh; Sahoo, Kedar; Mahiya, Lenin; Ojha, Harsh; Trivedi, Harshita; Parmar, Avanish Singh; Kumar, Manoj
• Is Part Of: Journal of environmental management. Volume 281(2021)
• Publication Date: 2021-03-01
• Subjects: Hydrogel -- Dye sorption -- Isotherm -- Kinetics -- Fixed bed adsorption study -- Breakthrough curve; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2020.111797
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: A low cost polyvinyl alcohol-glutaraldehyde cross-linked hydrogel beads were prepared and used for color removal from model industrial effluent containing Congo Red dye, using adsorption technique. The adsorption studies were performed using batch and fixed-bed reactor. Developed adsorbent, achieved adsorption capacity as high as ~34 mg of dye per gram of bead (condition: pH 6 and 45 °C). These beads were re-used for 7 times (many more runs possible) to remove the color from model dye effluent, without much loss in removal efficiency. Batch studies revealed a multi-layer adsorption governed by Harkins Jura model. Whereas the adsorption kinetics followed fractal like pseudo second order model, controlled by intraparticle diffusion phenomena. The fixed bed studies revealed steeper break through curves during adsorption operation when high dye influent rates and low bed height were used. This behaviour by the fixed bed reactor was best explained by the Thomas mathematical model. Studies further demonstrated that an external and internal mass diffusion become no more rate limiting during these experiments. Highlights: Low cost hydrogel beads were prepared by polymerization of PVA and glutaraldehyde. Beads acted as excellent adsorbent and repeatedly used for removing Congored dye. Thermodynamics favoured adsorption process and kinetics controlled by FL-PSO model. CR Dye sorption corroborated with Harkins-Jura isotherm and intraparticle diffusion. Bed depth and dye influent rate controled the adsorption breakthrough time in a fixed bed column.