Remediation of bio-refinery wastewater containing organic and inorganic toxic pollutants by adsorption onto chitosan-based magnetic nanosorbent

Abstract

<jats:title>Abstract</jats:title> <jats:p>The novelty of the current study deals with the application of magnetic nanosorbent, chitosan-coated magnetic nanoparticles (cMNPs), to be utilized for the management of lignocellulosic bio-refinery wastewater (LBW) containing three heavy metals and 26 phenolic compounds. The magnetic property of the adsorbent, confirmed by elemental and vibrating sample magnetometer analysis (saturation magnetization of 26.96 emu/g), allows easy separation of the particles in the presence of an external magnetic field. At pH 6.0, with optimized adsorbent dosage of 2.0 g/L and 90 min contact time, maximum removal of phenol (46.2%), copper (42.2%), chromium (18.7%) and arsenic (2.44%) was observed. The extent of removal of phenolic compounds was in the order: polysubstituted &amp;gt; di-substituted &amp;gt; mono-substituted &amp;gt; cresol &amp;gt; phenol. Overall, the adsorption capacity (qe) of cMNPs varies among the different contaminants in the following manner: copper (1.03 mg/g), chromium (0.20 mg/g), arsenic (0.04 mg/g) and phenol (0.56 mg/g). Post-adsorption, retrieving the cMNPs using an external magnetic field followed by single-step desorption via acid–base treatment is attractive for implementation in industrial settings. Reusability of the adsorbent was studied by recycling the cMNPs for five consecutive rounds of adsorption followed by desorption, at the end of which, cMNPs retained 20% of their initial adsorption capacity.</jats:p>

Preparation and application of magnetic chitosan in environmental remediation and other fields: A review

“…The recent advance in adsorption was the application of chitosan-coated magnetic nanoparticles (cMNPs) on an industrial scale that was evaluated by Karanam et al. 116 These magnetic chitosan-based adsorbents were used to treat lignocellulosic biorefinery wastewater from Quebec in Canada to absorb toxic metals and phenolic compounds. 116 The maximum removal of phenol (46.2%), copper (42.2%), chromium (18.7%), and arsenic (2.44%) were observed at pH 6.0, with an optimized adsorbent dose of 2.0 g/L, and for a period of 90 min.…”

“…116 These magnetic chitosan-based adsorbents were used to treat lignocellulosic biorefinery wastewater from Quebec in Canada to absorb toxic metals and phenolic compounds. 116 The maximum removal of phenol (46.2%), copper (42.2%), chromium (18.7%), and arsenic (2.44%) were observed at pH 6.0, with an optimized adsorbent dose of 2.0 g/L, and for a period of 90 min. The overall adsorption capacities for cMNP were copper (1.03 mg/g), chromium (0.20 mg/g) and phenol (0.56 mg/g).…”

Amino‐functionalised mesoporous silica microspheres for immobilisation of Candida antarctica lipase B – application towards greener production of 2,5‐furandicarboxylic acid

“…The elementary composition of the mesoporous silica microspheres was analysed using energy disruptive X-ray spectrometer (EDS). The analysis of the surface function groups of the mesoporous silica microspheres was performed in a Cary 660 FTIR spectrometer (Agilent Technologies, CA, USA) using potassium bromide pellet methodology in a wavelength range of 400-4000 cm −1 [22].…”