Abstract
Trimethyl borate (TMB) is crucial for applications ranging from organic synthesis to borohydride production, requiring efficient separation from methanol for optimal use. This study examines the effectiveness of pervaporation separation using blend membranes composed of chitosan (CS) and polyvinyl pyrrolidone (PVP) in various ratios in order to enhance pervaporation separation of TMB/methanol mixtures. Comprehensive characterizations of these membranes, addressing aspects like structural morphology, thermal and crystalline nature were carried out using techniques such as Fourier transform infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), contact angle measurements, Scanning electron microscopy (SEM) and X-ray Diffraction Analysis (XRD). Pervaporation experiment were conducted varying feed compositions, operational temperatures and PVP ratios. Evaluations revealed a noticeable improvement in permeation flux with increased PVP content. Two different blended membranes were subjected to cross-linking procedures in order to carefully evaluate its influence on their separation performance. The crosslinked PVP-CS-1 membrane showed good performance, achieving 146.37 selectivity. The optimal performance was achieved in an experiment utilizing a PVP-CS-2 membrane at 45°C, employing a mixture of 75 wt% TMB-25 wt% methanol, resulting in a recorded value of 335.44 g/m2h. Furthermore, the membrane exhibited excellent stability during 5 run experiment, showcasing robust mechanical and chemical stability.