Utilization of nanosilica from boiler ash sugar cane industry for filler of chitosan sulfate membrane on direct methanol fuel cell

Abstract

Nanosilica from boiler ash sugar cane industry can be utilized asfiller electrolyte membrane ofDirect Methanol Fuel Cell (DMFC). The aim of the study was to determine the influenceof ammonium sulfate addition on chitosan and nanosilica addition to performance of chitosan sulfate membrane. This research was conducted through three stages: synthesisof nanosilica using presipitation method, synthesis of chitosan sulfate with ammonium sulfate in various concentration of 0.1 M, 0.5 M, 1 M, 1.5 M, and synthesisof chitosan sulfate membrane by adding nanosilica of 1%, 3%, 5% level. The result showed that nanosilica produced had characteristicsof amorphous, 330 nm of particles size, 47.49 nm of crystal size, 64% of crystalinization degree, and 0.3 of Podispersity Index (PDI). The degree of sulfonation produced by chitosan sulfate was 15.86%, 19.00%, 22.84%, and 24.75%. The sulfonation chitosan and nanosilica addition gave significant effect (α = 0,05) of membrane characteristics. Membrane with 0.1 M of ammonium sulfate and 3% of nanosilica had the highest performance with 40.75% of water absorption, 44.22% of methanol absorption, 0.66meq/g of ion exchange capacity, and 6.48 × 10-4 S/cm of ion conductivity. The composite membrane can be applied for DMFC.