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Research on carbon dioxide free energy sources is increasing due to climate change, with green hydrogen gaining significant attention for its eco-friendly production process. This study focused on creating a diaphragm for alkaline water electrolysis using the TIPS method, utilizing the engineering thermoplastics PEEK and PPS for their excellent mechanical properties and heat resistance. DPK was employed as a diluent, and the phase diagram was established by measuring the crystallization temperature and cloud point based on polymer content. The morphology of the diaphragm, both surface and cross-section, was observed using an SEM, while tensile strength, alkaline stability, and permeability tests assessed its suitability for alkaline electrolysis conditions. The diaphragm with a polymer content of 20 wt% demonstrated a mechanical strength of 31.9 MPa, making it viable for operational use in alkaline electrolysis. All the diaphragms exhibited exceptional alkali resistance, with weight changes of less than 1 % in a 25 to 30 wt% KOH solution. Additionally, permeability tests indicated that permeability decreased as polymer content increased. Electrochemical evaluations revealed that the 20 wt% polymer content diaphragm achieved the best performance, delivering 188.7 mA/cm². This study confirms the potential of using these diaphragms in efficient and sustainable alkaline water electrolysis systems.

Various industries, such as food, petrochemicals, and pharmaceuticals, have recognized the importance of separation technologies for large molecules such as dye. A thin polyamide layer is commonly used in thin film composite membranes for separation applications, but fabricating a polyamide selective layer on hollow fiber (HF) membranes remains challenging. This research focuses on producing polyamide-based HF membranes by circulating aqueous and organic solutions during interfacial polymerization. By varying the solution flow rate, the dye rejection performance was investigated concerning morphology, polyamide thickness, mechanical properties, and hydrophilicity. All generated membranes consistently rejected over 98 % of congo red dye, with the highest rejection rate for methyl orange reaching approximately 92 %. The most efficient membranes were produced with an aqueous solution flow rate of 180 ml/min and an organic solution flow rate of 220 ml/min. These membranes exhibited notable ethanol permeance, with rejection rates of 99.75 % for congo red and 91.68 % for methyl orange. Additionally, they show promise for application in reverse osmosis processes for salt removal.

The need for green hydrogen through water electrolysis has propelled advancements in Anion Exchange Membranes (AEMs), positioning them as key components in AEM water electrolysis systems. This review paper comprehensively examines various commercial AEMs, focusing on their properties, stability, and performance in water electrolysis applications. By studying the characteristics of prominent AEMs such as Fumasep® FAA-3 Series, Tokuyama A201 and A901, Sustainion® X37-50, PiperION®, Aemion™, and Orion TM1, this review elucidates the correlation between membrane properties and overall performance. Special attention is given to stability and durability, crucial factors for long-term operation. Additionally, the compatibility of these AEMs with precious metal-free catalysts is explored, highlighting their potential in AEM water electrolysis application. These findings emphasize the significance of commercial AEMs in advancing the efficiency and sustainability of water electrolysis technology. This review presents as a useful source for scientists, engineers, and industry stakeholders attempting to get a comprehension of the properties and performance of commercial AEMs in water electrolysis technology, while also identifying avenues for future research and development. However, future studies to compare the commercial AEMs with the same testing conditions, and focus on the compatibility with PGM-free catalysts are needed.

In this study, we discussed the characterization and water treatment properties of the newly designed flower type membrane which has multi-bore structures prepared by the thermally induced phase separation process. The flower membrane for water treatment purposes was made of hydrophobic polyvinylidene fluoride polymer. The antifouling characteristics during the water treatment were studied using bovine serum albumin as a model compound and the chemical resistance was evaluated after long-term impregnation in hypochlorous acid (NaOCl) solution to understand the long-term stability of the membranes. Water permeability and mechanical strength of the membranes after prolonged chemical exposure was measured to observe the change in mechanical property and long-term performance of the membrane. Zeta potential measurements were used to find how the surface pollution affected the membrane performance and morphologies of the surface and crosssection of the membrane were confirmed by using scanning electron microscopy. To understand the efficiency of chemicals in the actual process, chemically enhanced backwashing was also carried out using citric acid and sodium hypochlorite in the lab-scale water treatment process.