| The conflicts between depletion of fossil and human demand for energy, as well as the impact of post-combustion on the environment has become one of the most serious problems in the 21st century. Hydrogen is considered the best alternative energy source because of its high heat value, less density. In addition, it is also clean and renewable.Currently, there are two ways of hydrogen preparation including chemical and biological methods. Biological hydrogen production focuses on three taxa as bacteria, blue algae and green algae. The cost of anaerobic dark fermentation and photosynthetic bacteria fermentation is relatively high to decompose organic matter. In addition, the process of photolysis of water for hydrogen production in green algae is extremely sensitive to oxygen and the reaction conditions are fairly harsh. While some kinds of filamentous cyanobacteria contain heterocyst and its structure can form a natural anaerobic environment, in which nitrogen-fixing nitrogenase enzyme catalyzes the reaction of hydrogen. Our study chose 10 kinds of filamentous algae for hydrogen production filter, and regulated these species. We got the best parameters of hydrogen production which provided a theoretical basis for the hydrogen industrialization with cyanobacteria.The specific results of this study is as follows:This study elected 10 types of filamentous cyanobacteria belonging to Cyanophyta, Cyanophyceae, Hormogonales, Nostocaceae and Anabaena of the genus Nostoc, Spirulina and Oscillatoria of the Osicillatoriaceae respectively. After hydrogen production cultivation, species of Nostocaceae have a hydrogen production capacity and especially, the Nostoc flagelliforme and Anabaena showed higher hydrogen production capabilities; Three species of Oscillatoria did not show any hydrogen production capacity in the air and light environment. In this study, after regulation of growth and hydrogen production cultivation of the algae Anabaena variabilis ATCC29413 we filtered out, we found that light intensity of 35μmol ? m-2 ? s-1, temperature of 28-30℃, the use of BG-II (-N ) as a medium, pH value of about 7.1, shaking culture for 15 days on the Anabaena variabilis ATCC29413, these conditions are the optimize parameters in photosynthetic growth phase of this algae. In addition, external conditions as argon gas under sealed environment, light intensity at 80μmol ? m-2 ? s-1, temperature of 30℃and static culture were most favorable on the hydrogen production. Its hydrogen production increased by more than 5 times, which reached about 8.4% of the total volume of gas. |
