| Autor: |
Mohammed Ali HSH; Department of Biological Sciences, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.; Princess Dr. Najla Bint Saud Al-Saud Center for Excellence Research in Biotechnology, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia., Sumiya; Department of Chemistry, University of Swabi, Anbar, Swabi 23561, Pakistan., Anwar Y; Department of Biological Sciences, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.; Princess Dr. Najla Bint Saud Al-Saud Center for Excellence Research in Biotechnology, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia., Al-Ghamdi YO; Department of Chemistry, College of Science Al-Zulfi, Majmaah University, Al-Majmaah 11952, Saudi Arabia., Fakieh M; Department of Biological Sciences, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia., Khan SA; Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, P.O. Box 80203, Jeddah 21589, Saudi Arabia.; Department of Chemistry, University of Swabi, Anbar, Swabi 23561, Pakistan.; Department of Chemistry, School of Natural Sciences, National University of Science and Technology (NUST), Islamabad 44000, Pakistan. |
| Abstrakt: |
MnO 2 and MnO 2 blended with 1 and 2 weight percent of activated carbon (AC), MnO 2 /AC1 and MnO 2 /AC2 were synthesized through the sol-gel method. The pure chitosan (CS) films were cast in the form of films. Similarly, 5 weight% of each MnO 2 , AC, MnO 2 /AC1 and MnO 2 /AC2 was intermingled with the CS to produce different films, such as CS-AC, CS-MnO 2 , CS-MnO 2 /AC1 and CS-MnO 2 /AC2. Zero-valent Co NPs were then supported on these films through the chemical reduction method and expressed as CS@Co, CS-AC@Co, CS-MnO 2 @Co, CS-MnO 2 /AC1@Co and CS-MnO 2 /AC2@Co NPs. All the catalysts were characterized by field emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS) and X-ray diffraction (XRD) techniques. The synthesized catalysts were used as a dip catalyst against the hydrogenation of 4-nitrophenol (4NP), and for the degradation of methyl orange (MO) and Congo red (CR) dyes. The k app and R 2 values were deduced from pseudo-first-order kinetics for 4NP and MO and zero-order kinetics for CR dye. The k app values of CS-AC@Co and CS-MnO 2 /AC1@Co NPs for 4NP hydrogenation were higher than those for any other member of the series, at 1.14 × 10 -1 and 1.56 × 10 -1 min -1 respectively. Similarly, the rate of CR degradation was highest with CS-AC@Co. The R 2 values for 4NP, MO and CR dyes were above 0.9, which indicated that the application of pseudo-first- and zero-order models were appropriate for this study. Furthermore, the antibacterial activity of all the catalysts was evaluated against Pseudomonas aeruginosa and Escherichia coli . The CS-AC@Co NPs exhibited the highest zone of inhibition compared to other catalysts against P. aeruginosa , while all the catalysts were inactive against E. coli . This study reveals that the catalyst can be used for the degradation of other pollutants and for microbial inhibition. |
