Design optimization of ceramic membrane filters based on a response surface method

Abstract

Ceramic membrane filters fabricated from local raw materials are excellent for municipal wastewater treatment. This paper studied the fabrication of ceramic membranes using Response Surface Methodology (RSM). It also looked at the influence of clay, palm kernel shell ash, kaolin, and starch on the properties of ceramic membrane filters. Optimal test conditions and procedures were determined by selecting a fitting model based on experimental data. The Box–Behnken design (BBD) was chosen for its ability to reduce the number of experimental trials, thus making it cost-effective. The BBD design was executed using Design-Expert 13 software (Stat-Ease, Inc., Minneapolis, MN, USA), requiring 29 experimental runs. According to the study, responses such as porosity, flow rate, thickness, and density were used in the model. The fabrication of the 29 ceramic membranes includes formulation, shaping (slip casting method), drying, and sintering. Based on RSM, an optimum ceramic membrane design was proposed: Kaolin = 413 g, Clay = 180 g, Starch 147 g, Palm Kernel shell ash = 13 g. Compared with the test results, this combination possesses favorable and reliable accuracy. The addition of kaolin played a role in creating a porous framework within the ceramic membrane. Clay serves as a binding agent, aiding the consolidation of ceramic particles within the membrane matrix. Starch served as a pore-forming agent during the fabrication process. From the study, the palm kernel shell ash served as a binder and a reinforcing agent, bolstering mechanical strength and structural robustness.