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Hessian cloth (jute fiber)-reinforced polypropylene (PP) composites were prepared by compression molding. The fiber content in the composites was about 50%. The resulting composites and also PP sheets were irradiated under gamma radiation of various total doses (250-1000 krad) at the rate of 600 krad/h. It was found that by using gamma radiation, the mechanical properties of the PP sheets and composites were improved. Gamma radiation dose of 500 krad showed better mechanical properties than that of other doses. Tensile strength and tensile modulus of the PP sheets improved 28% and 26%, respectively, and for composites 16% and 45%, respectively. On the other hand, bending strength and bending modulus of the PP sheet improved 16% and 125%. For composites, bending strength, bending modulus, and impact strength improved 12%, 38%, and 62%, respectively. Water uptake of the composites at 258C was measured and it was found that treated samples had lower water uptake properties. It was found that the dielectric constant is higher for the treated composite than that of the untreated one. The transition temperatures were found to be 808C for untreated and 758C for irradiated composites, respectively. Conductivity of the composites decreases due to irradiation.

The occurrence of micropollutants (MPs) in various streams of municipal wastewater treatment plants (WWTPs), and their fate and removal processes are discussed. The fate of MPs in WWTPs largely depends on adsorption on suspended particulates, primary and secondary sludge and dissolved organic carbon, and removal occurs due to coagulation-flocculation, and biodegradation. The log Kow (>2.5) and pKa are the dominant properties of the MPs, and the concentration, organic fraction, and surface charge of suspended particulates dictate the extent of adsorption of MPs. Most of the conventional WWTPs do not remove complex MPs by biodegradation or biotransformation effectively (kbio ≤0.0042 L/gss/h), and the removal varies widely for different compounds, as well as for the same substance, due to operational conditions such as aerobic, anaerobic, anoxic, sludge retention time (SRT), pH, redox potential, and temperature. Membrane bioreactor performs better for moderately biodegradable compounds due to the diverse nature of microorganisms as well as greater adaptability due to longer SRT. Ozone and UV-based advanced oxidation processes, membrane filtration can be used for tertiary treatment due to their high rate as well as easy implementation. Various partition coefficients and rate constants values for different MPs are also provided for design and application.

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