Study On Perstraction With Composite PDMS Membrane

Perstraction is a new development of membrane separation technology. It has many advantageous features and wide application prospects to bioconversion and biodegradation of organic compounds. As a new and important membrane process, perstraction has been studied comprehensively on many aspects by researchers of the world. However, there are still many problems to need to be solved prior to real industrial application. These problems include membrane and its material, membrane module, transport mechanisms and kinetics through membrane, process apparatus and system, and so on. For bioconversion and biodegradation of organics, we are interested in a MBR integrating perstraction membrane into a bioreactor. At present, studies on perstraction were mostly achieved in laboratories, and the modules are tubular. The investigating object was on biodegradation of volatile organic compounds in waste water. In this work, a perstraction module with PDMS-PA flat-plate membrane was developed for investigating some aspects of perstraction applicable to bioconversion, such as, characteristics of perstraction separation process, operation modes and parameters, mass transfer through membrane, distinction between perstraction and pervaporation. Perstraction behaviors for five organics including vanillin, catechol, ketone, xylitol and ethanol, was examined, and overall mass transfer coefficients of these species through membrane were measured. Perstraction process with the module was analyzed by using resistance-in-series model.An emphasized study for perstraction of vanillin through membrane has been...