Okra Micro-Cellulose Crystal (MCC) and Micro-Clay Composites for the Remediation of Copper, Nickel, and Dye (Basic Yellow II) from Wastewater

Abstract

Water pollution by contaminants such as toxic metals and dyes is now a major concern due to their high toxicity and persistence in the environment. Advances in nanotechnology have enabled the use of micro/nanomaterials to treat and purify water in various industries. In this study, Bijoypur clay was modified with ethyldiamine and incorporated into an okra fiber (Abelmoschus esculentus) micro-cellulose crystal (MCC) to produce a composite that could absorb copper (Cu), nickel (Ni), and dyes like basic yellow (II) from industrial wastewater. Composites were prepared using different percentages of MCC and clay. Atomic absorption spectroscopy (AAS) was used to determine the concentrations of Cu and Ni whereas a UV–Visible spectrophotometer measured the absorbance of basic yellow (II). The synthesized composites were extensively characterized using a range of techniques including thermogravimetry (TG) and differential thermogravimetry (DTG), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Results show that both the MCC and clay could absorb Cu, Ni, and basic yellow (II) from the contaminated wastewater. The MCC and clay composite showed the maximum efficiency of metals removal, which was up to 95% (24 mg/g) for Cu at pH 6, 20 min contact time, 2 g/L adsorbent dose, and 100% (31 mg/g) for Ni at pH 8, 60 min contact time, and 2 g/L adsorbent dose, respectively, at the initial concentration of 50 mg/L. The maximum dye uptake capacity of 85% (19 mg/g) was observed by the MCC and clay composite under optimized conditions at the initial concentration of 50 mg/L, pH 8, 30 min contact time, and 1 g/L adsorbent dose compared to the pure clay, which had an efficiency up to 26% for Cu and 24% for dye removal. All of the results indicate that incorporating clay into MCC increases the absorption capacity of contaminants from wastewater, which could be more effective for environmental applications compared to untreated cellulose.

Synthesis, characterization, and cytotoxicity studies of nanocellulose extracted from okra (Abelmoschus Esculentus) fiber

“…The applications of okra fibers in textile industries have a few downsides such as sensitivity to wear, poor fastness to rub as well as color, and a higher tendency to crease. Furthermore, previous studies demonstrated that common bleaching or alkalization chemical treatments failed to enhance the fiber's mechanical properties significantly for their probable use as fillers in composite materials [ [20] , [21] , [22] ]. This advocates that the usage of okra bast fibers as the raw material of nanocellulose can be a practical substitute for engaging them as technical fibers in textile products.…”