The goal of this research was to remove iron oxide from Ibute-Nze kaolin by dissolving the clay mineral in an aqueous oxalic acid solution and optimizing the process. The chemical composition of the raw and modified clay was determined using x-ray fluorescence, and the morphology of the solid sample was determined using a scanning electron microscope. The best conditions for the oxalic acid leaching of iron-oxides impurity from Ibute-Nze kaolin were determined using response surface methodology based on Box-Behnken design. The studies were carried out within the following process parameter ranges: 40–90 leaching temperature; 0.075-0.355mm particle size; 1–6 mol/dm3 acid concentration; 0.02–0.12 g/cm3 kaolin sample to acid ratio and 30-240 min contact time. The characterization revealed that Ibute-Nze clay is kaolinitic in nature and calcination at 750 opens more pores for its leaching. According to the analysis of variance, a second-order polynomial regression equation provided the best fitting for the experimental data. The predicted and experimental response values were shown to be correlated (R2 = 0.9276) in the experimental runs. The following were found to be the best conditions for the leaching process variables: 83.2051 leaching temperature, 0.0827mm particle size, 3.6179mol/dm3 acid concentration; 0.0287g/cm3 kaolin to acid ratio and 217.932min reaction time. The chemical leaching process was 92.6035 per cent under these conditions, which made the clay good for industrial applications.
The purpose of the research was to compare the properties of snail shell particulate (SSP) and its derivatives to those of commercial chitosan (CC) as potential adsorbents. Chitin (CT) was synthesized by deproteinizing and demineralizing SSP with dilute sodium hydroxide (NaOH) and hydrochloric acid (HCl) solutions, respectively. Chitosan (CH) was prepared by partially deacetylating CT with concentrated NaOH. The extracted CH was modified with 10.00% (w/v) oxalic acid (CH<sub>ox</sub>). Energy dispersive X-Ray (EDAX), Fourier transform infrared (FTIR), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), and chromium adsorption were used to characterize the materials. FTIR spectra of CT and CH materials showed the presence alkyne, nitrile, primary and secondary amines/amides groups with 83.98% as the degree of deacetylation. The spectra of EDAX of CT and CH samples showcased predominant peaks, which correspond to calcium, oxygen, yttrium, and silver. SEM images showed tight, porous, and fractured surface for CT and CH materials unlike the snail shell and CC. BET surface area of the adsorbents were in the increasing order of CT<CC<CH<sub>ox</sub><SSP<CH. CH has a greater surface area of 362.32 m<sup>2</sup>/g and a mesoporosity of 71.41%. However CH<sub>ox</sub> with moisture content 1.52%, bulk density of 0.58 g/cm<sup>3</sup>, ash content (AC) 0.47% and pH 10.24, has better advantage to be used as biosorbent compared to CC with moisture content 1.08%, bulk density of 0.49 g/cm<sup>3</sup>, AC 0.87% and pH 8.58. CH<sub>ox</sub> had a higher chromium adsorption of 80.4 mg/g at a concentration of 150 mg/L, while having a relatively smaller surface area of 325.38 m<sup>2</sup>/g (68.36% mesoporosity). The potential removal techniques include ionic interaction between chromium ion and functional groups and surface adsorption due to the textural characteristics of adsorbent samples. When compared to CC, snail shell particle and its derivatives are potential good adsorbents.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.