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Particulate and planar catalyst configurations are modelled for the STD reaction.• A crystallite-pore network model is adapted to describe the catalytic configurations.• For the different configurations, the accordant optimum catalyst ratio is presented.• Porosity in structured catalysts strongly effects CO-conversion and DME-selectivity.• Best performance by hybrid configurations of close proximity and planar double layer.

A 39-W thermoelectric generator prototype has been realized and then installed in industrial plant for on-line trials. The prototype was developed as an energy harvesting demonstrator using low temperature cooling water waste heat as energy source. The objective of the research program is to measure the actual performances of this kind of device working with industrial water below 90 °C, as hot source, and fresh water at a temperature of about 15 °C, as cold sink. The article shows the first results of the research program. It was verified, under the tested operative conditions, that the produced electric power exceeds the energy required to pump the water from the hot source and cold sink to the thermoelectric generator unit if they are located at a distance not exceeding 50 m and the electric energy conversion efficiency is 0.33%. It was calculated that increasing the distance of the hot source and cold sink to the thermoelectric generator unit to 100 m the produced electric energy equals the energy required for water pumping, while reducing the distance of the hot source and cold sink to zero meters the developed unit produces an electric energy conversion efficiency of 0.61%.

Hydrothermal synthesis is the state-of-the-art technique for the preparation of zeolites and related porous solids. However, when it comes to the preparation of nanosized zeolites, this technique is limited by low yields, separation problems and high amounts of waste. In this work, we utilized the strengths of a combination of spray drying and steam-assisted crystallization (SAC), also known as dry gel conversion, to reduce these problems. At spray drying temperatures between 300 and 400 °C, it was possible to convert all the amorphous material via SAC into zeolite particles without extra addition of template. Kinetic studies of SAC revealed that about 4 to 8 days are needed to achieve the formation of a 100% crystalline product. The newly formed crystalline phase was crystallized on the surface of the nanosized zeolites and led to a slight increase in the primary particle size while the macroscopic morphology of the spray-dried aggregates was preserved. This work demonstrates that the combination of spray drying and SAC are useful tools in supplementing the hydrothermal synthesis of nanosized zeolites.