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In the present study, polyethersulfone (PES) membranes on a macroporous alumina support was prepared by solvent-deposition method to separate H2/CH4 mixture. The membrane solution viscosities were determined in order to understand the effect of PES concentration on the formation of selective membranes over a support. Supported PES membranes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and single gas permeability measurements of H2 and CH4. The membrane casting solution with 20% PES concentration provided the formation of defectless single-layer supported membrane. At lower concentrations, the penetration of membrane casting solution into the pores of support was prevented by using intermediate layer, hence the prepared 2-layered membrane performance was improved. H2/CH4 ideal selectivity of best membrane exhibited is 73 at 35 °C, which shows promise for H2/Hydrocarbon separation. [ABSTRACT FROM AUTHOR]

Waste mineral oil pollution causes serious environmental damages in long term. It affects the availability of nutrients in top layer of soil which is rich in organic matter and prevents the entrance of water and oxygen to the soil. In this study, two different mineral oil (1% and 5%) doses were amended to soil-soil+wastewater sludge samples and then an incubation study was performed during three months. Ammonium nitrogen, nitrate nitrogen, total nitrogen and hydrolysable (H) nitrogen forms (HO-amino nitrogen, HO-amide nitrogen, HO-hexozamine nitrogen, HO-rest nitrogen) were analyzed in samples. The results of the study indicated that total nitrogen concentrations in mineral oil containing soils were decreased at the end of the incubation period. It is determined that nitrogen mineralization and nitrification processes were inhibited in soils contaminated with high doses of mineral oil. The magnitude of hydrolysable nitrogen forms was found to be as H-amino-nitrogen>H-rest nitrogen=H-amide-nitrogen>H-heksozamine nitrogen. It was found that the percentages of hyrolysable nitrogen in total nitrogen varied between 94% and 96%. The results have indicated the faster mineralization of amino acids and accumulation of mineral nitrogen as amid N fraction, as well as the preferential use of mineral oil C as carbon source by microorganisms during the process. [ABSTRACT FROM AUTHOR]