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Kaolin has been found to be a more economical alternative in ceramic hollow membrane fabrication compared to alumina, silica, and zirconia despite having similar properties. However, it was discovered that apart from having high mechanical strength and the ability to withstand high operational temperature, the kaolin membrane has the tendency to dissolve in a high alkaline solution. Hence, in this study, zirconia (ZrO2) was imposed to kaolin suspension as co-starting material due to its stable hexagonal properties with kaolin to overcome this drawback. To study the dissolution property of the modified kaolin-based membrane, a phase inversion technique was used to fabricate zirconia-kaolin hollow fiber membrane (ZKHFM) followed by immersion in ammonium hydroxide (NH4OH) as an alkaline solution. Ammonia was aptly chosen for it being considered as one of the pollutants to be removed from wastewater. The mechanism, morphology and properties of the membrane were investigated in terms of sintering temperature, morphology, mechanical strength, pore size and porosity The results showed that ZKHFM with 10 wt% (ZK-10) with sintering temperature of 1,200 °C had the best performance in terms of having high mechanical strength (21MPa), excellent permeation flux (∼1,600 Lm2/h) and lowest dissolution (0.01 g dissolute) at pH 13, indicating the ability of ZKHFM to be used in alkaline solution.

Water is an essential commodity that supports the very existence of life on earth; hence, contamination of ground and water bodies with harmful substances liberated by landfill leachate can seriously impact the environment and well-being of mankind. In this context, explorations in search of economically attractive avenues to treat landfill leachate merit scientific pertinence. A response surface methodology approach based on a three-factor three-level central composite design was applied to compare and optimize the removal of ammoniacal nitrogen (NH3–N) from landfill leachate. In this study, the efficacy of natural zeolite, clinoptilolite, and synthetic zeolite, Sigma 96096, as adsorbents was investigated for parameters, viz. zeolite dosage, particle size, and ratio of leachate to distilled water, respectively. Under optimized conditions, clinoptilolite (2 g/L, 50 μm, and 50%) and Sigma 96096 (4 g/L, 150 μm, and 50%) effectively removed 58.2% and 37.8% of NH3–N, respectively. The equilibrium isotherms of both sorbents for the sorption of NH3–N were also well described by the Freundlich and Langmuir adsorption isotherms, respectively. The study found clinoptilolite was more efficient than Sigma 96096 in removing NH3–N, envisaging its suitability for complementing the current treatment processes to treat landfill leachate.