Fabrication and characterization of kaolin based membrane for catalyst recovery

Abstract

In this project work, Kaolin was the primary raw material for membrane fabrication. Various additives/binders were also used based on their suitability and effectiveness in imparting special properties e.g. mechanical strength and dispersion properties for homogeneity to the final or finished membrane. During membrane preparation with various stoichiometric compositions of ingredients, it was observed that higher percentages of kaolin didn’t result into membranes with good flexural strength whereas increasing the % of red-mud enhanced the mechanical strength quite considerably e.g. 10.11 MPa (membrane F), 18.93 MPa (membrane G) and 12.04 MPa (membrane H) respectively. Methanol permeation studies showed that the average steady state flux was highest for membrane G (ca. 4.23×10-4 m3 m-2 sec-1). The fabricated membranes were undergone catalyst recovery study in a batch membrane module. In this work, Cu-BTC (or, HKUST-1 or, MOF-199), a well-known Metal Organic Framework (MOF) was selected as the potential catalyst. Several cycles (or batches) were carried out inside the membrane module and it was observed that membrane G performed better than the rest and a recovery percentage of ca. 61% was noted after 3 cycles before the membrane pores were completely choked. Membrane de-fouling and regeneration studies were carried out in detail using back-washing treatment inside the module itself and ultra-sonication techniques for preparing the membranes for next round of operations.