Mechanistic approach on comparative biosorption of dyes by extracellular polymer of Ochrobactrum pseudintermedium C1 utilizing waste mineral lubricating oil

Abstract

AbstractDyes are widely used in manufacturing of various consumer products for their ability to impart characteristic color. However, dyes are also one of the most important hazardous pollutants in this present day. Presence of hydroxyl, phosphate, ether, carbonyl and alkyl groups also enable bacterial extracellular polymers to function as biosorbent. In this study, negatively charged biosorbent EP-C1 produced by Gram-negative bacterium Ochrobactrum pseudintermedium C1 utilizing waste mineral lubricating oil has given different decolorization percentages for triphenylmethane cationic Malachite Green and azoic anionic Congo Red at neutral pH. Time wise absorbances from Ultraviolet-Visible Spectrophotometry has estimated maximum biosorption of Malachite Green after 300 min. Biosorption capacities have differed with initial dye concentrations, biosorbent dosages and contact time. Time taken by each dye to reach saturation has depended upon their charged bearing groups of each dye and biosorbent. Kinetic (pseudo first and pseudo second order) and diffusion (intra particle and liquid film) parameters in presence of different dye concentrations and biosorbent dosages were studied for understanding the biosorption mechanism. Morphological differences in chemical structure, chemical functional groups of EP-C1 and EP-C1 loaded dye was studied by Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy and Zeta potential measurements. A compiled overview on comparative mechanistic biosorption of Malachite Green and Congo Red dyes by a bacterial extracellular polymer in miniature laboratory shake flask experiments was done in this study. Newer advents on biological remediation of dyes with mineral lubricating oil as sole carbon source can add a new feather to the already available bioremediation techniques in mitigation of hazardous wastes.Keywords: Biosorbentbiosorption mechanismcharacterization techniquesdyesextracellular polymerlaboratory scale experimentwaste mineral lubricating oil AcknowledgmentsThe authors gratefully acknowledge (i) Department of Chemical Technology, University of Calcutta (ii) Department of Polymer Science and Technology, University of Calcutta (iii) Centre for Research in Nanoscience and Nanotechnology, University of Calcutta for instrument facilities and (iv) Asianol Factory, Kolkata, West Bengal, India for oil samples.Authors’ contributionsThe study was conceptualized by Sriparna Datta and Ishika Saha. The methodology of the study was developed by Sriparna Datta and Ishika Saha. Result analysis and investigation of the study was done by Ishika Saha. Original draft of the manuscript was written by Ishika Saha. Revision and editing of the manuscript was done by Ishika Saha, Sriparna Datta and Dipa Biswas. Laboratory equipment, reagents, chemicals required for the study was arranged by Sriparna Datta and Dipa Biswas.Disclosure statementNo potential conflict of interest was reported by the author(s).Data availability statementThe authors declare that furnished data had not been published or under evaluation elsewhere.