The potential of burned water hyacinth (BWH) for phenol adsorption from aqueous solution was studied. Batch kinetic and isotherm studies were carried out under varying experimental conditions of contact time, phenol concentration, adsorbent dosage and pH. The pH at the point of zero charge (pH PZC ) of the adsorbent was determined by the titration method and the value of 8.8 ± 0.2 was obtained. The FTIR of the adsorbent was carried out in order to find the potential adsorption sites for the interaction with phenol molecules. The Freundlich and Langmuir adsorption models were used for the mathematical description of adsorption equilibrium and it was found that the experimental data fitted very well to the Langmuir model. Maximum adsorption capacity of the adsorbent was found to be 30.49 mg/g. Batch adsorption models, based on the assumption of the pseudo-first-order and pseudo-second-order models, were applied to examine the kinetics of the adsorption. The results showed that kinetic data closely followed the pseudo-second-order model.

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Jute (Hessian cloth) reinforced polymer composites were prepared with a mixture of 2-hydroxy ethyl methacrylate (HEMA) and aliphatic urethane diacrylate oligomer (EB-204), and then cured under gamma radiation. Thick pure polymer films (2 mm thickness) were prepared by using the same monomer and oligomer at different weight ratios, and 500 krad of total gamma radiation dose at 600 krad/hr was selected for the curing of all composites. Total radiation dose, jute content, and monomer concentration were optimized with the extent of mechanical properties. Among all resulting composites, the composite of 38% jute content at monomer:oligomer ¼ 50:50 (w/w) ratios showed the better mechanical properties, such as 108% increase in tensile strength (TS), 58% increase in bending strength (BS), 138% increase in tensile modulus (TM), and 211% increase in bending modulus (BM) relative to pure polymer film. The gel content values were also found to increase with the increase of jute content in the composite. But the elongation at break (Eb) for both tensile and bending was found to decrease with increasing jute content. The best mechanical properties were obtained when jute fibers were pre-irradiated with UV radiation, such as 150% increase in TS, 90% increase in BS relative to polymer film, 19% increase in TS, and 15% increase in BS relative to untreated jute-based composites. A water uptake behavior investigation of the resulting composites was also performed and composites based on UV-treated jute showed the minimum water uptake value.

Jute fiber (Hessian cloth) and E-glass fiber (mat)-reinforced, unsaturated polyester (USP) resin along with additives and initiator, composites are prepared by the hand layup technique at room temperature (25 C). Jute fiber content in the composites is optimized with the extent of mechanical properties, and composites with 25% jute show higher mechanical properties. The mechanical properties are found to increase with the incorporation of dissimilar portions of glass fiber into the jute fiber-reinforced composite. Among all the resulting hybrid composites, the composite with a jute to glass ratio of 1 : 3 demonstrates improved mechanical properties, such as tensile strength (TS) 125%, tensile modulus (TM) 49%, bending strength (BS) 162%, and bending modulus (BM) 235% over untreated jute composite. To further improve the properties, the surface of jute and glass fiber is irradiated under UV radiation of different intensities. UV pretreated jute and glass fibers (1 : 3) at optimum intensities show the highest mechanical properties, such as TS 70%, TM 33%, BS 40%, and BM 43% compared to untreated jute-and glass-based hybrid composites. UV-modified jute/glass-reinforced hybrid composites also show the best of Charpy impact strength (40 kJ/m 2 ). The interfacial adhesion between jute/glass and USP is monitored by a scanning electronic microscope (SEM).