Modelling and optimization of antibacterial composite membrane by using box-behnken

• Main Author: Siti Nur Shafina, Binti Sabaruddin
• Format: Final Year Project Report
• Language: English; English
• Published: Universiti Malaysia Sarawak (UNIMAS) 2017
• Subjects: TP Chemical technology
• Online Access: http://ir.unimas.my/id/eprint/25661/1/Siti%20Nur%20Shafina%2824pgs%29.pdf; http://ir.unimas.my/id/eprint/25661/2/Siti%20Nur%20Shafina%28fulltext%29.pdf; http://ir.unimas.my/id/eprint/25661/

The main objective of this is research is to develop a regression model and to optimize the performance of antibacterial composite membrane. The parameters that are to be optimized are the concentration of antibacterial additives, the composition of solvent/non-solvent system in the casting solution and the composition of coagulation bath. The concentration of silver nitrate (AgNO3) as antibacterial additives was varied between 1.0 g to 2.0 g, while the percentage of N-methyl-2-pyrrolidone (NMP) as the solvent in the casting solution is varied from 90wt% to 100wt%. The percentage of ethanol in the coagulation bath was varied from 0wt% to 25wt%. The Design of Experiment (DoE) was conducted by using 3-factorial 3-level Box-Behnken. The performance of the membranes fabricated were evaluated in terms of membrane flux and antibacterial activity in term of E. coli inhibition, which served as the responses for the modelling and optimization purposes. The modelling and optimization process were conducted by using Response Surface Methodology (RSM). The resultant equations showed R 2 values of 0.9003 and 0.9789 for the membrane water flux and E. coli inhibition respectively. The analysis of variance (ANOVA) proved that both models were significant. Based on the results, it was observed that weight percentage of NMP in casting solution and weight of AgNO3 added had significant impact on the membrane water flux and E. coli inhibition. Optimum values of parameters for preparation of antibacterial composite membrane were obtained using multiple response method for 70% E. coli inhibition as target value. Based on the optimization results, the best membrane water flux, which was 19.49 L/m2 h, was obtained at weight percentage of NMP in casting solution of 95.61%, weight percentage of ethanol in coagulation bath, and weight of AgNO3 of 1.26 g, with desirability of 1. Keywords; Optimization, antibacterial, silver nitrate, NMP, Box-Behken,