News flash April 2012

New HybSi® publications

Functionalization of HybSi® membrane technology

In a recent paper, published in the Journal of Materials Chemistry, we show for the first time the results of the incorporation of functional groups into a hybrid silica network. Membranes containing various terminating amino groups, like 3-aminopropyl­triethoxy­silane and 3-(2-aminoethylamino)­propyl­trimethoxy­silane (see to the right), were prepared. These membranes show remarkable low gas permeations while the water flux in a pervaporation experiment remain essentially unchanged from the conventional materials. The unique properties of these amino-functionalized membranes allow for selectivity improvement which is not solely dependent on pore size or defect control, but also on affinity, and therefore open up a highly promising option. For a complete description of these findings please visits the RSC website:


Acetal preparation: a process study

In the last couple of years ECN has collaborated closely with the Engineering Faculty of Bilbao on the design of a cost effective process for the large scale production of 1,1-diethoxy butane (see News­flashes 10 and 13). The final analysis for this topic was a techno-economic comparison of various options. The essential trick was to integrate the membrane separation with the distillation step in a recycle loop. This way, azeotropes do not hinder the otherwise complex distillation. As only pure reactants are being recycled, a conversation of almost 100% can be achieved. This value is much higher than the equilibrium value of ~40% and that of a membrane reactor, ~70%. The full paper with the complete analysis is available on line from Wiley: