International Congress on Membranes and Membrane Processes date:23-29 July 2011
Pervaporation process is a newly developed technique in separation technology. Although development is still at its infancy, this technique’s convincing performance in most organic dehydration applications (e.g. dehydration of ethanol) has attracted interest from various researchers for further examination. Pervaporation process itself is a simple process and easy to operate when compared with other conventional separation process, e.g distillation. This study focuses on the potential of pervaporation applied for water removal in high-concentration acetic acid solutions. This study also demonstrates a novel application of polymer in acetic acid dehydration using a polyphinylsulfone (PPSU) membrane. Three types of membrane were prepared internally, with polymer composition of 25wt% PPSU (25PPSU), 27.5wt% PPSU (27.5PPSU) and 30wt% PPSU (30PPSU). The pervaporation study was conducted using 90wt% of acetic acid as a feed solution at temperature of 30oC to 80oC. It is observed that 27.5PPSU provided the optimum operating condition with highest averaged separation factor of 8.41. On the other hand, 25PPSU and 30PPSU generated averaged separation factors of 4.94 and 7.49 respectively [Table 1]. The highest flux was observed when utilizing 25PPSU, which was assessed to be 0.8111 kg/m2.h [Figure 1]. As a consequence, this resulted in the lowest separation factor. High flux property always comes with a low separation factor, therefore, a good balance between flux and separation factor in membrane separation process is crucial. There are a few factors which may contribute to the membrane effectiveness, among others are; type of polymer, solvent, non-solvent, cross-linking agent and also method of preparation. In economical consideration, the easiest, the simplest and the cheapest material which can produce stable and good membrane performance is always preferred. Hence, it is found that the pervaporation technique, when applied using a suitable and stable type and of membrane, gives the best and the most realistic outcome for the dehydration of acetic acid and water.