Modification and characterization of hydrophobic beeswax-agar/ceramic composite membrane for feasibility to degasifier applications

Abstract

Membrane technology is one of the best methods for removing unwanted dissolved gases in industrial systems due to its durability and reduced use of chemicals. However, alternative materials that solved the high cost and chemical usage of current materials made composite membranes interesting options. Composite membranes, which combined the advantages of different materials, were an attractive alternative. They combined the durability of inorganic support materials such as ceramics with the environmental friendliness and low cost of biopolymers. This study focused on modifying and characterizing biopolymer/ceramic composite hydrophobic membranes to evaluate their potential use for degasifier applications. The alumina-kaolin support membrane tubular was fabricated using the gelcasting method. Alumina and kaolin were chosen because they were low-cost materials that provided a strong, porous structure. Meanwhile, red seaweed agar was used as the intermediate layer because of its cost-effectiveness and unique gelling process, which created a strong three-dimensional structure. Additionally, beeswax was used as the top layer to enhance water resistance. Surface analysis using SEM and contact angle measurements showed that the alumina-kaolin support had rough pore structure and a low water contact angle, indicating good water permeability. Coating with 1-4 wt % of agar solution reduced water permeability, resulting in a contact angle between 88.16� and 97.15�. Higher concentrations of agar resulted in a smoother and more uniform surface. From FE-SEM analysis, surfaces coated with beeswax in the ratio of 5-25 wt % rough surface, especially at low wax concentrations. Cross-sectional analysis showed well-adhered layers, indicating good adhesion, and significantly improved hydrophobicity. Contact angles between 122.74� and 125.44� were obtained, with the highest hydrophobicity and lowest surface energy at low beeswax concentrations (5-10%). Performance tests showed that the membrane composite could withstand pressures ranging from 0.5712 to 2.5656 bar, with optimum results achieved at 5-10 wt % of beeswax coating. This research highlighted the potential of using agar and beeswax to produce low-cost, hydrophobic composite membranes. This was an attractive alternative method for industrial degasifier applications.?????????????????????????????????????????????????????????????????????????????????????? ?????????????????????????????????????? ???????????? ???????????????????????????????????????????????? ???????????????????????????????????????? ???????????????????????? ???? ??????????????????????????????????????????????????????????????? ????????????? ??????????????????????????????????????????????????????????????????? ?????????????/??????????????????? ?????????????????????????????????????????????????????? ???????????????????????????????????????????? ?????????????????????????????????????????????????????????????????????????????????? ????????????????????????????????????????????? ????????????????????????????????????????????????????????????????????????????????????? ????????????????????????????????????????????????????????? ??????????????????????? SEM ??????????????????????? ?????????????????-????????????????????????????????????? ??????????????? ???????????????????????????????????????? ???????????????????????????? 1-4% ?????????? ????????????????????????? ????????????????????? 88.16� ??? 97.15� ????????????????????????????????????????????????????????????????????????????? ??????????????? FE-SEM ?????????????????????????????????????????????? 5-25% ????????????????????????? ??????????? ???????????????????????? ??????????????????????????????????????????????????? ???????????? ???????????? ????????? ????????????????????????????????????????????????????????? ?????????????????????? 122.74� ??? 125.44� ???????????????????????????????????????????????????????????????????????????????? (5-10%) ???????????????????????????????????????????????????????????????????????? 0.5712 ??? 2.5656 ???? ???????????????????????????????????????????????? 5-10% ?????????? ????????????????????????????????????????????????????????????????? ????????????????????????????????????????? ????????????????????????????????????????????????????????