Application of organic acid functionalized cellulose for batch and aqueous two-phase extraction of sulfonamides from different matrices

Antibiotics are among the most widely used drugs globally, with fluoroquinolones, macrolides and sulfonamides being commonly prescribed. Sulfonamides, which form the basis of several sulfa drugs, have significant applications in both medicinal and synthetic organic chemistry. While these substances are effective in their intended uses, their negative environmental impact raises serious concerns. Sulfonamides can have toxic effects on aquatic ecosystems, leading to the disruption of microbial communities, bioaccumulation in organisms and the development of antibiotic resistance. To mitigate these effects, cellulose and its functionalized derivatives were investigated for their ability to adsorb sulfonamides from real wastewater, milk and honey samples. To improve adsorption, cellulose was functionalized with oxalic and adipic acid. The resulting sorbents were then analyzed using FTIR, PXRD and SEM techniques. Based on FTIR analysis the optimal reaction time for cellulose functionalized with adipic acid and oxalic acid via hydrothermal treatment in an autoclave was 1 h at a temperature of 50℃. Furthermore, the FTIR data revealed the emergence of ester moieties from the esterification reaction of carboxyl groups in the organic acids and the hydroxyl groups on cellulose. Based on PXRD analysis for the adipic acid functionalized cellulose contained a hybrid of adipic acid and oxalic acid peaks, indicating functionalization of cellulose. Batch adsorption experiments were conducted using sulfonamide based analytical standards: sulfachloropyradazine and sulfabenzamide, to evaluate the adsorption capability of cellulose and its functionalized derivatives at varying temperature, time, and mass of sorbent. The multivariate based optimal conditions for the adsorption of sulfachloropyradazine and sulfabenzamide using cellulose was 25°C, 180 min and 5 mg and with extraction efficiency of 70 and 51%, respectively. The optimal conditions for adsorption of sulfachloropyradazine and sulfabenzamide using oxalic acid functionalized cellulose was 25°C, 30 min and 50 mg with extraction efficiency of 64 and 75%, respectively. Adsorption of sulfachloropyradazine and sulfabenzamide using adipic acid functionalized cellulose was 25°C, 30 min, and 5 mg with extraction efficiency of 70 and 51%, respectively. Although cellulose functionalized with adipic and oxalic acid showed some influence on the adsorption behavior of sulfachloropyridazine and sulfabenzamide, the adsorption of sulfachloropyridazine was slightly reduced from 70% with unmodified cellulose to 64% with the functionalized form. Functionalizing cellulose with adipic and oxalic acid adds carboxyl and hydroxyl groups, enhancing adsorption of sulfachloropyradazine and sulfabenzamide through stronger hydrogen bonding, electrostatic interactions, and possibly π-π stacking, compared to cellulose. Overall, the functionalization of cellulose with these acids is a promising approach for enhancing the adsorption of sulfonamides which could be applied in wastewater treatment.

Author dc:creator

• Shikweni, Mbuyelo

Advisors dc:contributor.advisor

• Mokgehle, T.
• Tavengwa, N. T.
• Ndou, D. I.

• Sulfonamides
• Cellulose functionalization
• Oxalic acid
• Adipic acid
• Adsorption
• Wastewater treatment
• Sulfachropy
• Sulfachropyridazine Sulfabenzamide
• UCTD

Statement dc:rights

• University of Venda

Language dc:language.iso

en

Repository record dc:identifier.uri

https://univendspace.univen.ac.za/handle/11602/3002

OAI identifier oai:identifier

oai:univendspace.univen.ac.za:11602/3002