Fluoride Bio-Sorption Efficiency and Antimicrobial Potency of Macadamia Nut Shells

Materials

Rabelani Mudzielwana¹  Humbelani H. Nekhavhambe¹  Mugera W. Gitari¹  Wasiu B. Ayinde¹  Oisaemi U. Izevbekhai¹ 

[1] Environmental Remediation and Nano Science Research Group, Department of Geography and Environmental Sciences, Faculty of Science, Engineering and Agriculture, University of Venda, Private Bag X5050, Thohoyandou 0950, South Africa;

关键词: antimicrobial potency;    bio-sorption;    chemisorption;    fluoride;    macadamia nut shells;   

DOI  :  10.3390/ma15031065

来源: DOAJ

【 摘 要 】

This paper presents the potential application of macadamia nut shells (MNS) in the bio-sorption of fluoride and its antimicrobial potency against common pathogens encountered in surface water resources. The efficiency of MNS in the sorption of fluoride was determined using batch mode experiments, while the antimicrobial potency was investigated using the well disc diffusion assay method. The maximum fluoride sorption capacity of 1.26 mg/g was recorded at an initial fluoride concentration of 5 mg/L, adsorbent dosage of 0.5 g/100 mL, contact time of 120 min and initial pH of 6. The adsorption kinetics data were better described with a pseudo second order model, indicating the dominance of the chemisorption mechanisms. The Langmuir adsorption isotherm model described the isotherm data suggesting a monolayered adsorption. The thermodynamic parameters, ∆Gº and ∆Hº, confirmed that F⁻ sorption by MNS is a spontaneous and endothermic process. The bio-sorbent was regenerated for seven continuous cycles when HCl was used as regenerating solution. The antimicrobial studies revealed that MNS has minimal activity towards Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae. The MNS showed potentials for application in bio-sorption of fluoride. However, the doping of MNS with metal ions is recommended to enhance its anti-microbial potency.

【 授权许可】

Unknown