Silver-nanoparticle Supported on Nanocrystalline Cellulose using Cetyltrimethylammonium Bromide: Synthesis and Catalytic Performance for Decolorization of Dyes

We reported that the ultrasonically synthesized nanocrystalline cellulose (NCC) from microcrystalline cellulose has the capacity for use as natural and green matrices for the synthesis of silver nanoparticles. Cationic surfactant cetyltrimethylammonium bromide (CTAB) was employed as a modifier and stabilizer for NCC. The structure of as-synthesized composite (Ag/CTAB/NCC) was characterized by Fourier transform infrared spectroscopy (FT-IR); field emission scanning electron microscopy (FE-SEM); Transmission electron microscopy (TEM); Energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The XRD pattern confirmed the single cubic phase of Ag nanoparticles with a crystallite size of about 30 nm. The catalytic activity of Ag/CTAB/NCC has been analyzed by performing the reduction of certain toxic azo methyl orange dye (MO) (by two methods) and aromatic nitro compound of 4- nitrophenol (4-NP) in shorter time. The reduction of MO to hydrazine derivatives and 4-NP to 4-aminophenol takes place with pseudo-first-order rate constants. The reduction time regularly decreased and the rate of reduction (k) increases (3 fold) with increasing catalyst amount in method (2) (mmol NaBH4/mmol MO = 250 and 42 mg catalyst) compared to the method (1) (mmol NaBH4/mmol MO = 400 and 5 mg catalyst). The results indicated that spherical AgNPs immobilized CTAB-adsorbed NCC showed better catalytic activity and shorter reduction time towards the removal of methyl orange (k = 14.2 × 10-3 s-1, t =150 s) and 4-nitrophenol (k = 5.4 × 10-3 s-1, t = 180 s) compared with previous works that could be introduced as an effective method for the catalytic treatment of wastewater.