Preparation of dense and defect free PES flat sheet membranes for H2/CH4 separation

The production parameters of flat sheet membranes for achieving dense, defect or bubble free structure and repeatable permeation results have been evaluated. Solvent evaporation rate and drying method are the main important manufacturing components which should be determined carefully. The SEM and permeation results helped to evaluate whether the structure is fully dense or not. The results of permeability for three dense film membranes were similar to each other. The final acceptable method is preparation of 15 wt% solution of polyethersulfone (PES) in n-methyl 2-pyrollidone (NMP) and solvent evaporation in two steps. The final bubble free structure was assessed by SEM analysis and obtained average permeability and selectivity was 7.3 barrer and 70 respectively.

Keywords:

dense film , hydrogen , membrane , permeability , selectivity