Mixed matrix materials comprised of molecular sieve domains embedded in processable polymer matrices have the potential to provide membranes with higher permselectivity and equivalent productivity compared to existing membrane materials. It has been shown that successful mixed matrix materials can be formed using relatively low glass transition (T g ) polymers that have a favorable interaction with the sieves. This article extends this earlier work to include the use of more practical rigid matrix polymers with high T g s that can ultimately be used in forming high-performance mixed matrix layers for composite membranes. Initial attempts to form mixed matrix materials based on high T g polymers with a type 4A zeolite resulted in poor adhesion between the polymer and sieve. Correcting this problem was pursued in this study by forming the composite material close to the T g of the polymer by addition of a plasticizer to match the matrix T g with the solvent volatility. Forming the films at elevated temperatures presented substantial challenges, and this work discusses overcoming these challenges in detail. With some modifications in the film casting procedure, successful materials were achieved. Promising oxygen/nitrogen transport results are presented for these zeolite 4A-Matrimid/plasticizer membranes, and this data compares favorably with predictions of the well-known Maxwell model for composite systems.

This paper presents primary research results on nutrient emissions, resulting water quality and ecological impacts of the Kharaa river basin (Mongolia) during a three-year water resource management study. Based on surveillance data from Mongolian environmental authorities and a complementary own monitoring scheme we calculated nutrient emissions on a sub-basin scale. Additionally, the ecological situation of fish fauna, macroinvertebrates and their habitats were investigated on selected river sections in order to link anthropogenic pressures, nutrient status and ecological impact. was estimated. Main contributors are urban settlements with a high proportion of households without connection to wastewater treatment plants and, to a lesser extent, agricultural land-use. These nutrient levels have a significant eutrophication potential in the Kharaa River and we observed functional shifts of the macroinvertebrates and fish fauna, while the drinking water abstraction through bank filtration showed no significant alteration of raw water quality. DedicationHORST BEHRENDT developed the conceptual nutrient emission model MONERIS, which was designed for the river systems in Central Europe (see VENOHR et al. 2011 With the publication of this study we present the results of his modelling approach and the implications for an innovative water quality assessment in data-scarce regions.

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