Preparation and Characterization of Inorganic Membranes for Hydrocarbon Separation from N2 for Environmental Applications

Abstract

This paper reports the preparation and characterization of a tubular alumina and silica membrane for propylene (C 3 H 6 ) and nitrogen (N 2 ) separation. Dip-coating technique was employed to prepare silica membrane. Nitrogen adsorption measurements reveal that this membrane possesses mesostructure with pore diameter of 3.940 nm and BET surface of 0.484 m 2 /g. Scanning electron microscopy (SEM) studies show that the layers are defect free and energy diffraction X-ray analysis (EDXA) confirms the compositional element of silica. Propylene and nitrogen permeation tests also confirmed that the membrane is defect free with C 3 H 6 /N 2 selectivity of 1.79 higher than ideal Knudsen selectivity.

Role of ZrO2 in TiO2 composites with rGO as an electron mediator to enhance the photocatalytic activity for the photodegradation of methylene blue

“…It has also been reported that the bands that appeared in the spectra (400-1200 cm À1 ) characterized the metallic connection M-O-M, O-M-O or M-OH (where in this case M = Zr or Ti). 79 The strong absorption band at 594 cm À1 can be assigned to the vibrations of the Zr-O or Ti-O functional groups, but separate elucidation of bands related to Zr-O-Ti, Zr-O-Zr or Ti-O-Ti is not possible for mixed compositions. Finally these results suggest that the existence of interfacial contact between ZrO 2 , TiO 2 and rGO can lengthen the lifetime of photo-generated electron-hole pairs and thereby enhance the photocatalytic activities of GT and GTZ-20 composites.…”