Study On The Isolating Microorganisms For Synergistic Converting Pharmaceutically Industrial Syngas Into Ethanol

Along with the rapid development of pharmaceutical industry,the pollution of atmospheric environment becomes increasingly severe,pharmaceutically industrial syngas has been recognized as one of the important factors,therefore,the management of pharmaceutically industrial syngas pollution is imperative.Currently,activated carbon adsorption,direct combustion,condensation recovery,absorption and biological treatment technology are the main technology applied to treat industrial syngas.And biological treatment technology uses microbes to convert industrial syngas into materials harmless to the human body or available,with the advantages of high efficiency,low cost and no secondary pollution.It plays an increasingly important role in the aspect of pharmaceutically industrial syngas treatment.This study attempts to use microbiological fermentation to deal with pharmaceutically industrial syngas.Under the action of microorganisms,pharmaceutically industrial syngas can be converted to ethanol.Ethanol has a wide range of uses in health care and 75% ethanol is a kind of disinfectant,at the same time,it is one type of rare clean,convenient and safe energy,and the trend of renewable resources research in the world.This study can not only solve the problem of pharmaceutically industrial pollution emissions,but also make waste profitable,and relieve the energy crisis.Firstly,it screens acetyl coenzyme A pathway that can be efficient used from activated sludge and convert the CO₂ into acetic bacteria.Measuring the ability to produce acetic acid under the cultivation environment of different nitrogen source,carbon source and the initial pH value to obtain the optimum growth condition to produce acetic acid bacteria.It is also found that adding a certain amount of yeast extract in fermentation medium can effectively improve the metabolic ability of acetic acid bacteria,and increase the acetic acid content produced by metabolism;Secondly,the establishment of CO₂/H₂ rich pharmaceutically industrial syngas producing ethanol process conditions needs to use egg shell,iron powder to mix with different acids to prepare CO₂ and H₂,realize the simulation of pharmaceutically industrial syngas by mixing and study the influence of CO₂/H₂ throughput and proportion on overall acetic acid and ethanol production.Experiments show that it is suitable to use the reaction rate and gas production rate of 0.4 g iron powder and 1.91 mol/L strong phosphoric acid to get H₂,whose output is 32 mL H₂ after 8hrs.The preparation of CO₂ applies the reaction rate and gas production rate of 1.9 g egg shell and 0.61 mol/L glacial acetic acid,the putout of is 220 m L CO₂ after 8hrs;It then makes acetogen synergistic fermentation with S.cerevisiae P145 and C.acetobutylicum AS05 to examine its ability to produce ethanol under different nitrogen source,carbon source,temperature and pH value cultivation environment.It is found that S.cerevisiae P145 shows the produced ethanol is more efficient and greater concentration on the condition of 5% glucose medium than 10% glucose medium.The output for ethanol concentration is 18.61 g/L,the best fermentation temperature is 30? and optimum fermentation PH is 7.In the case of no other carbon source,maximum ethanol concentration of C.acetobutylicum AS05 is 15.78 g/L,which indicates the best ethanol production characteristics.Thirdly,using 5 L displacement type fermentation tank to conduct synergistic fermentation laboratory enlarging experiment and verify the realizability of optimization system.Studies have shown that compared with shaking flask experiment,ethanol production is improved if using 5L fermentation tank to conduct the experiment,which has certain industrial production feasibility.