Methane Sulfonic Acid Influence on Membrane Electrode Assembly Preparation Using Mixture of (Sulfonated Chitosan, Carrageenan, Polyvinyl Alcohol, Multi-Walled Carbon Nano Tubes, Glutaraldehyde) Injected between two Diffusion Gas Electrodes
Sri Widarti1, Lina Troskialina2, Yanti Suprianti1

1 Energy conversion Engineering, Politeknik Negeri Bandung
2 Chemical Engineering, Politeknik Negeri Bandung

Abstract

To overcome the problem of environmentally unfriendly and expensive synthetic PEM in direct methanol fuel cells, PEM from natural polymers that are environmentally friendly and renewable is interesting to develop. Natural polymers that develop as PEM are carrageenan and chitosan because they can absorb water and have functional groups as a medium to transport protons from the anode to the cathode. Functional groups played as ion exchange in the membrane. To increase the ion exchange capability and hydrophilicity of the membrane, sulfonation of the functional groups on chitosan was carried out. Chitosan was sulfonated using methane sulfonic acid with concentrations of 6.9, 8.3, 9.6, 11.0, and 13.8 g/gr of polymer material. To reinforce, the mixture of sulfonated chitosan, carrageenan, and polyvinyl alcohol solution was added by MNCNTs and crosslinked by glutaraldehyde. Due to difficulty attaching the membrane between two electrodes, the research aim is developing membrane electrode assembly (MEA) methods. MEA was carried out by injecting the mixture solution of sulfonated chitosan, carrageenan, polyvinyl alcohol-MNCNTs, and glutaraldehyde between two electrode diffusion gases. So that, the crosslinking reaction occurred between two electrodes. The morphology of the anode-membrane-cathode interface was studied microscopically. The SEM image shows that the anode-membrane-cathode interface is quite tightly bonded. The MEA formed is attached to a single cell holder. The performance of a single fuel cell was carried out using 3 M methanol fuel. From the testing, it was found that the greater the concentration of methane sulfonic acid (13,8%) in the chitosan sulfonation process, the greater the OCV (602 mV), ion exchange capacity (0.0053 mek g-1), and the ability of water absorption (42%), and vice versa for methanol permeability (6.9 x 10-09 cm2s-1).

Keywords: MEA, DMFC, Chitosan, Carrageenan, MWCNTs

Topic: Renewable energy