This report describes work performed during Phase II of the project ?Treating Coalbed Natural Gas Produced Water for Beneficial Use by MFI Zeolite Membranes.? Ion separation by MFI-type zeolite membranes was successfully demonstrated in our previous work (Phase I). The pure silicalite membranes synthesized by in-situ crystallization show high ion separation efficiency (>90%) but low water flux (~0.12 kg/m2.h). The main challenge revealed in our previous study is how to enhance the water flux and to scale up this material for practical application. The work in Phase II attacks these difficult problems, targeting synthesis of high flux zeolite membranes with enhanced water flux and development of post-synthesis modification. Several efforts have been made in Phase II to enhance the water flux and ion rejection, as well as to improve the reproducibility of zeolite membranes.