Optimization of Hydrogen Production from Pickle Bamboo Shoot Wastewater by Rhodopseudomonas palustris TN1

Abstract

A pickle bamboo shoot is a top marketing product in the East of Thailand, especially Prachinburi province. Vinegar (acetic acid) and sea salt (NaCl) are added during pickle bamboo shoot productions to preserve the color and texture. These high acidity (pH 3-4), high salt concentration (6.0%) and dark-brown color of the pickle bamboo shoot wastewater (PBSW) lead to the difficulty for bioremediation of PBSW treatment. Rhodopseudomonas palustris TN1 was capable of surviving in 3.0% (w v^-1) NaCl medium and produce hydrogen under anaerobic-light condition. The Aim of this study is to investigate the ability of biohydrogen production in the PBSW by TN1, the effect of initial pH (6.5, 7.0 and 7.5) and light intensities (1,000, 3,000 and 5,000 lux) were performed under anaerobic-light condition. The hydrogen content in biogas using wastewater as the medium was found to be 98.51%. The optimal condition for the highest hydrogen production was pH 7.36 and light intensity of 3,200 lux at room temperature (30±2ºC) giving hydrogen 73.57±5.29 mL L^-1 and dry cell weight (DCW) of 5.36±0.51 g L^-1 within 96 hrs. In conclusion, TN1 can consume the PBSW as a carbon source to produce hydrogen.