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A thirst for water: Organic-inorganic hybrid silica nanosieve membranes with narrow pore size distributions were developed for the separation of binary (bio)alcohol/water mixtures, for example, to remove water from wet biofuels during production. These membranes dehydrate lower alcohols and show a stable performance in the presence of significant amounts of acetic acid.

Microporous membranes are a promising option for energy-efficient molecular separations. Longterm hydrothermal stability of the membrane material is of prime importance for several industrial processes. Here, a short overview of silica-based membrane materials and their hydrothermal stability is presented. Following this, the development of a series of organic-inorganic hybrid silica sols is described, based on a,x-bis(triethoxysilyl)-precursors with bridging methane, ethane, propane, and benzene groups. High-throughput screening was used to scan a range of sol parameters, followed by membrane preparation from the most promising sols. These organicinorganic hybrid silica (HybSi Ò ) membranes were used in dewatering of lower alcohols by pervaporation. Separation factors up to 200 were found for ethanol/water mixtures, and up to 23 for methanol/water mixtures. Modest permselectivity values for hydrogen over nitrogen were found, ranging up to 20.7 for the shortest bridging group. It was concluded that the length of the organic bridge has a clear effect on the pore size distribution and the selectivity of the membrane.

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This article reports evidence for substantial public support for the large-scale deployment of three renewable energy options in Kenya: wind, solar PV, and geothermal energy. With these renewable technologies, the government of Kenya could make a large contribution to reaching its national commitment under the Paris Agreement. Prices, infrastructural needs, and land-use requirements importantly contribute to shaping public opinion about these renewable energy alternatives, in different ways and directions for wind, PV, and geothermal energy. While overall the evaluation of these technologies is positive, public authorities should be wary of the possible inconveniences and drawbacks associated with them. Anticipating and, where possible, mitigating these shortcomings in national climate and energy development plans could preclude some of them becoming possible hindrances for broad-scale adoption of wind, PV, and geothermal energy. Furthering quantitative public acceptance studies, like the one presented here based on (semi-)expert elicitation and information-choice questionnaires, can assist in Kenya fully reaching its national climate and energy ambitions. More generally, we argue that the establishment of affordable, clean, and secure energy systems, as well as the mitigation of global climate change, can benefit from stakeholder engagement and public survey analysis like the one performed in our study-in developing countries as much as in the developed part of the world.

The cover picture shows the membrane separation of water (blue arrow) from crude ethanol (red arrows) as a key enabling technology in the production of ethanol from lignocellulosic biomass. This technology is generally considered to be one of the more viable options for the transition to a sustainable transportation fuel supply. In their Communication on page 158, J. F. Vente and co‐workers describe the preparation and performance of an amorphous bridged silsesquioxane‐based membrane characterized by Si–CH2–Si building units. This new organic–inorganic hybrid silica membrane allows the dehydration of ethanol and, to some extent, methanol. Even the presence of 1.5 wt % acetic acid does not affect the separation performance of these membranes.magnified image