A fabrication of a low-cost zeolite based ceramic membrane via phase inversion and sintering technique

The usage of ceramic membranes is gaining enormous attention due to their higher selectivity, permeation rate, and chemical and thermal stability as compared to the polymeric membrane. Owing to the fact of these superior properties, the search of a low-cost ceramic membrane is still in demand. To date, the fabrication of ceramic membrane using natural zeolite as the membrane ceramic loading has yet to be explored. Thus, this study aims to develop natural zeolite (Clinoptilolite) as the ceramic source in the fabrication of low-cost hollow fibre ceramic membrane (HFCM) via phase inversion and sintering techniques. Several fabrication parameters were also studied namely air gap distance, bore fluid flow rate and sintering temperature throughout this research. The best ceramic membrane was fabricated using 5 cm air-gap distance, 13 mL min-1 of bore fluid flow rate and 1000 °C of sintering temperature. The acceptable strength and morphological behaviour of finger-like and sponge-like voids were found to be an advantageous characteristic of the fabricated membrane. The cheap and yet abundant raw ceramic material as well as low sintering temperature are eventually reduced the cost of membrane production

Superhydrophobic ceramic hollow fibre membranes for trapping carbon dioxide from natural gas via the membrane contactor system

The membrane contactor system is one of the most important technologies to trap CO2 from natural gas. To apply this technology, hollow fibre membranes with a superhydrophobic surface must be used, where membranes were prepared from kaolin clay through the phase inversion/sintering technique and modified by three types of fluoroalkylsilane (FAS) molecules (C6, C8, C10) at different immersion times (6, 24, 48,72 h) to capture CO2 from natural gas via contacting the gas-liquid system. The kaolin was chosen due to its abundant availability at an affordable price as well as the high amount of the hydroxyl (OH) group in the surface which easily reacts with FAS during the grafting process. Superhydrophobicity was distinguished by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), liquid entry pressure of water (LEPw) measurement, and contact angle (CA). The lowest pore size of the grafted membrane obtained for C8 was about 1.32 μm; it was considered the perfect target for high membrane resistance. The chosen superhydrophobic kaolin membrane was tested for carbon dioxide (CO2) capture via the membrane contactor system. With increasing time of immersion, the hydrophobicity phenomena rose gradually until superhydrophobicity property was obtained. Forty-eight hours was proven as sufficient time to obtain the desired superhydrophobicity property to avoid wetting pores of the membranes. Besides, the perfect type of FAS for separating CO2 was C8 based on the sufficient LEPw and contact angle. The reduction of pH was observed after testing the performance of using a membrane contactor to separate CO2 by using water as absorbent where pH value decreased from 6.6 to 4.3 within 1 h, which concludes the success of the gas-liquid system into removing CO2 from natural gas

Novel ceramic hollow fibre membranes contactor derived from kaolin and zirconia for ammonia removal and recovery from synthetic ammonia

The adverse effects of ammonia found in wastewater streams lead to the development of advanced water treatment technology, i.e. membrane contactor (MC). In this study, single layer hollow fibre membrane (SLZK) and dual layer hollow fibre membrane (DLZK) were prepared from zirconia and kaolin and modified into hydrophobic membrane through simple grafting process via fluoroalkylsilane (FAS) agent. The properties of membranes such as morphology, surface roughness, mechanical strength, wettability and liquid entry pressure were analysed through scanning electron microscopy (SEM), atomic force microscopy (AFM), 3-point bending strength, contact angle and LEPw setup. Finally, the performance of the membranes was also investigated towards ammonia removal via membrane contactor system