Obtaining electrical energy from starch: influence of HCl, temperature and substrate

Abstract

The processis is studies for obtaining electrical energy from the decomposition of starch using HCl (0.0762N) in a single step it is proposed to make the reactions of hydrolysis and oxidation- reduction almost simultaneously. The study variables are: temperature (14-36 ° C), ratio of starch (g) / water (mL) (1/80- 1/160), relative concentration of HCl (1x10-3, 2.5x10-3, 4.8x10-3 and 9x10-3 N) and lifetime. Voltaic cells were used containing water and starch, separated by a membrane of cellulose acetate. HCl was added only to half a cell it. [Graphite electrodes and a voltage measuring multitester completes the circuit voltages are obtained when the concentration of HCl is 9x10-3N, lower concentrations make the system unstable with very low voltages. High concentrations of HCl produce the breaking of the starch chain, therefore more molecules react for oxidation-reduction process stabilizing the system for energy production. At temperatures of 28 to 30 ° C were generated higher voltages. Likewise, the ratio Water (ml) / Starch (g) of 150/1 led to higher voltages, possibly because they favor the dissociation of HCl. Thus, it would have a higher concentration of protons to pass through the membrane to the other half cell, and generates oxidation-reduction reactions which results in higher voltage in the cells. Under the studied conditions the cells have a lifespan of 338 hours (14 days), which is the same number of days reported in their work Jacacody about lintnerization of cereal starch granules. The highest voltage recorded at the end of their useful life is 214.0 mV].