A biohybrid nanomaterial of biosynthesized TiO₂ NPs from Mangrove leaf and shrimp shell-based Chitosan: ultrasonic-assisted synthesis and its application for methylene blue removal and COD reduction of real industrial wastewater

Abstract

In the present study, TiO₂ NPs (particle size: 25–35 nm) were biosynthesized from the Mangrove leaf extract. These nanoparticles were used to modify chitosan, and Chitosan@TiO₂ biohybrid nanomaterial was synthesized and characterized using FTIR, XRD, BET, and, EDX-FE-SEM analyses. The adsorption ability of Chitosan@TiO₂ nanomaterial has been investigated for Methylene blue (MB) removal from aqueous solution. The results indicated that the amount of MB removal is high in alkaline pH (optimum pH = 9). The pseudo-second-order model was able to describe the effect of contact time on the adsorption ability. The Langmuir model well described the equilibrium manner, and one gram of Chitosan@TiO₂ could attract 416.66 mg of MB. Kinetic data, values of parameters of activation energy (+57.283 kJ/mol), enthalpy (-86.8148 kJ/mol), and Gibbs free energy (-27.999 to −22.8987 kJ/mol) indicate the dominance of chemical adsorption over physical adsorption. The breakthrough curves of 3 adsorption/desorption cycles showed the acceptable ability and reusability of prepared nanomaterial. Synthesized biohybrid nanomaterial can reduce 75% COD and 79% nitrate of the effluent from industrial city no.3 of Yasouj. The results of this research show the high ability of chitosan@TiO₂ biohybrid to remove dyes from wastewater and reduce the pollution load of industrial wastewater.

NOVELTY STATEMENT

This research’s novelty is synthesizing a biohybrid nanomaterial from TiO₂ NPs (biosynthesized from Mangrove leaf) and chitosan (synthesized from food wastes (shrimp shells) via a sonochemical process). These biomaterials have been synthesized via fast and simple processes to reduce the use of hazardous and expensive chemicals. The Chitosan@TiO₂ nanocomposite has a high adsorption capacity for cationic dye removal from aqueous solution, COD reduction, and nitrate removal from Industrial city wastewater.

Keywords:

• Biosynthesis of TiO₂
• Mangrove leaf
• Shrimp shell-chitosan

Disclosure statement

The author reports there are no competing interests to declare.