Membrane technology plays an increasingly important role in developing a more sustainable process industry. Zeolites are a novel class of membrane materials with unique properties enabling molecular sieving and affinity based separations. This thesis proposes some new concepts in zeolite membrane synthesis, application, and modeling. The influence of zeolite polarity is assessed and the use of a hydrophobic zeolite membrane for water separation is explored. Ozonication, a novel method for zeolite detemplation, is studied and applied to zeolites, membranes, and coated sensors. Modeling based on non-equilibrium thermodynamics and molecular modeling is applied to give insight in membrane transport. Furthermore, an optimization of a novel hybrid membrane separation/crystallization process is presented.