Silver nanoparticles stabilized in polymer hydrogels for catalytic degradation of azo dyes.
Fabrication of poly-(N-isopropylmethacrylamide-co-methacrylic acid) [p(NMA)] microgels to be utilized as microreactors to synthesize stable Ag nanoparticles for catalytic reductive degradation of dyes has been addressed in this work. Both p(NMA) microgel and Ag-p(NMA) hybrid microgel systems have been analyzed by Fourier transform infra-red and Dynamic light scattering, Ultraviolet-Visible spectroscopy, X-ray diffraction and Transmission electron microscopy. Catalytic activity of Ag-p(NMA) towards reductive degradation of Congo Red (CR), Methyl Orange (MO) and Alizarin Yellow (AY) was investigated under different operating conditions. Spectrophotometry was employed to check the progress of reaction while the rate constant (kapp) value of degradation reaction was determined under various conditions to optimize reaction parameters for rapid and economical degradation of these dyes. An increase in kapp value was observed by increasing feed content of dye up to a certain value that decreases again by further increment in dye concentration which reflects that catalysis follows Langmuir-Hinshelwood mechanism. A gradual increase in the kapp value was also observed with increasing quantity of hybrid microgel used as a catalyst. By comparing kapp values of degradation of aforementioned dyes, it was found that Ag-p(NMA) hybrid microgel gives better activity for MO dye degradation in comparison to catalytic degradation of CR and AY.
['Iqbal|Sadia|S|', 'Zahoor|Chandani|C|', 'Musaddiq|Sara|S|', 'Hussain|Murid|M|', 'Begum|Robina|R|', 'Irfan|Ahmad|A|', 'Azam|Muhammad|M|', 'Farooqi|Zahoor H|ZH|']
D001391:Azo Compounds D002384:Catalysis D004396:Coloring Agents D003224:Congo Red D020100:Hydrogels D053768:Metal Nanoparticles D046529:Microscopy, Electron, Transmission D011108:Polymers D012834:Silver D013053:Spectrophotometry D014961:X-Ray Diffraction
Silver nanoparticles Polymer hydrogels Catalytic degradation Azo dyes