SYNTHESIS AND CHARACTERIZATION OF HYBRID MEMBRANES OF MODIFIED POLYVINYLIDENE FLUORIDE ZEOLITE CLINOPTILOLITE ORGANO MERCAPTO SILANA (PVDF/ZEOLITE-MPTMS) FOR MICROFILTRATION OF METHYLENE BLUE

• Main Author: DWIHERMIATI, ELSA
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/64834
• Institution: Institut Teknologi Bandung

Water pollution by dyes is one of the problems currently being faced, mainly due to the increase in the textile industry. One method to overcome this problem is to use membrane technology as a water filtration technology. The membrane material that is widely used is polyvinylidene fluoride (PVDF), this is due to several advantages of PVDF membranes such as having good mechanical properties, good thermal properties, and good chemical resistance. The PVDF membrane has hydrophobic properties which can cause the membrane to be easily clogged or fouled by foreign particles on the membrane surface, thereby reducing the separation efficiency and membrane life. To reduce these constraints the membrane can be modified by mixing polymer solutions with inorganic materials to increase the hydrophilicity of the membrane, mechanical strength ,and membrane porosity. Zeolite is an inorganic material that is hydrophilic and is widely used as a filler in membranes. The addition of inorganic materials into hydrophobic polymers such as PVDF can produce low homogeneity due to differences in polarity and easy agglomeration to form. Therefore, zeolite is modified by adding silane compounds to increase the polarity so that a more homogeneous membrane can be produced The purpose of this research was to study the performance and characteristics of PVDF/Zeolite and PVDF/Zeolite-MPTMS membranes. In this study, the first modification of the zeolite was carried out with 3-mercaptopropyl trimethoxy silane (MPTMS), the modified results were characterized by FTIR and XRD. From the FTIR results, it can be concluded that the zeolite was successfully modified by MPTMS which was indicated by the appearance of a peak at wave number 2934 cm-1 which was the stretching vibration of -CH. From the XRD characterization results, it was found that the type of zeolite is a clinoptilolite zeolite, as evidenced by the appearance of a diffraction peak which is a typical peak of clinoptilolite zeolite. Furthermore, the modified zeolite was used in the synthesis of PVDF/Zeolite-MPTMS hybrid membrane with a concentration variation of 0.25; 0.5; 0.75; 1.0 %w/w. The porogen used in this research is polyethylene glycol (PEG). The composition of PVDF and porogen used was fixed at 18 and 4% w/w. The composition of the solvent is adjusted to the composition of the zeolite or zeolite/MPTMS added. The solvent used is N,N -dimethyl acetamide (DMAc). The synthesis method used is the phase inversion method, by finding the optimum composition of the ratio of PVDF and zeolite. The obtained hybrid membranes were characterized using FTIR, porosity test, hydrophilicity, pore radius measurement, morphology test using SEM, and thermal iv stability using TG/DTA. Membrane performance based on permeability, stability using TG/DTA. Membrane performance based on permeability test, antifouling based on FRR value and selectivity using methylene blue dye with dead-end flow system. The addition of zeolite increased the porosity of the membrane, and increased the selectivity to methylene blue, while there was a decrease in the permeability, hydrophilicity, and pore radius of the membrane. The optimum concentration of zeolite is on the PVDF/Zeolite membrane 0.75% w/w with a permeability value of 23.08 L/m².h and a rejection percent of 96.96%. The addition of zeolite-MPTMS decreased hydrophilicity, increased porosity, pore radius of the membrane, permeability and membrane selectivity. The optimum concentration of zeolite-MPTMS is 0.75% w/w with a permeability value is 36.99 L/m².h and a rejection percentage is 95.53%. The antifouling ability of the membrane was measured by the value of flux recovery ratio (FRR) which was calculated by comparing the water flux on the membrane before and after being used for filtration of methylene blue dye. The results of the FRR test showed that after the addition of zeolite and zeolite-MPTMS there was a decrease from 90.63% to 81.14% in PVDF/Zeolite and 82.05% in PVDF/Zeolite-MPTMS. From the results of this study, it can be concluded that the membrane with optimum performance is 0.75% w/w PVDF/Zeolite-MPTMS membrane because it has the highest flux with a high rejection value for methylene blue.