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Waste paper-reinforced sodium alginate/carboxymethyl cellulose (NaCMC)-based bio-composite films were prepared by solution casting method by optimum combination of 1.5% sodium alginate and 1.5% NaCMC. The optimum combination was selected on the basis of good tensile strength and low moisture sensitivity. This film was further subjected to aqueous solution of potassium aluminium sulphate (potassium alum) to reduce water vapour permeability and moisture content. This potassium alum solution treatment further enhanced the mechanical and thermal properties, and the film biodegradability was not affected either due to the cross linking or colour addition, which has potential as a substitute for the currently used polyethylene-based films. Molecular interactions between polymers and potassium alum affected mechanical, thermal, and other properties and was confirmed by Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray, and thermo gravimetric analysis of the films. This bio-composite film may be suitable to replace non-biodegradable and costly biodegradable packaging materials.

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The adsorption removal of C.I Reactive Blue 21 (RB-21) dye from aqueous solution by commercial MCC was successfully modified with aminopropyltriethoxysilane. The various physiochemical attributes like initial dye concentration, contact time, solution pH, adsorbent dose and temperature were evaluated. The surface modification was characterised and confirmed with specific surface area analyser using Brunauer-Emmett-Teller, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, Energy Dispersive Spectrometer and X-ray diffraction. The adsorption kinetics, isotherms, and thermodynamics were explored. The Langmuir, Frendlich and Redlich-Perterson isotherm models were studied with the Langmuir adsorption isotherm model showing the best fit with the adsorption capacity of 30 mg g − 1 at 323 K. The kinetic data was considered using pseudo-first-order and pseudo-second-order. The results indicated that the pseudo-second-order model was preferred with good correlation. The thermodynamic attributes like changes in standard enthalpy, standard entropy and standard Gibbs free energy were assessed at different operating temperatures. Hence, current research work shows efficient removal of RB-21 dye from effluent solution by modified microcrystalline cellulose.

Meta-aramid fibre is very difficult to dye because of its very high crystallinity. The major issues with dyeing meta-aramid fibre are its selective dyeability with a particular class of dye and poor light fastness, especially with basic dyes, which is not acceptable. In this work, various dyeing trials of meta-aramid fabric with two commercial basic dyes, Bezacryl Golden Yellow GL 200 and Bezacryl Blue FBS, were conducted on high temperature-high pressure and infrared dyeing machines. To improve the light fastness of dyed samples, titanium dioxode nanoparticles were applied on dyed fabric using a layer-by-layer technique. Fastness properties such as light, wash and rubbing were checked for untreated and titanium dioxode-treated samples. Titanium dioxode application on dyed material improved the light fastness of Bezacryl Golden Yellow-dyed samples significantly, and Bezacryl Blue FBS also showed an improved rating compared with that previously reported. Improvement in light fastness is selective but it is still a novel and viable route to improve the light fastness of dyed meta-aramid fabrics.