Effect Of Key Environmental Factors On The Formation Of MEC Anode Membrane

At present,with the large amount of fossil energy,energy crisis and environmental pollution have become two major problems which people have to face.It is urgent to need a clean and efficient energy.Hydrogen which has clean and efficient characteristics is the most popular new energy source.Due to thermodynamic constraints,in the traditional hydrogen production process hydrogen production efficiency is not high.MEC hydrogen production technology can not only use the fermentation end products for hydrogen production,but also can be used for wastewater treatment,so it has broad application prospects of environmental protection and new energy development and other fields.With the development of MEC hydrogen production technology,a lot of research have been done on the MEC reactor configuration,hydrogen production substrate,methane production and so on,and the hydrogen production performance of MEC has been improved.However,the fundamental principle of the MEC hydrogen production technology is still not very clear.The anode microbial membrane plays an important role in the MEC hydrogen production,which is an important place for the growth and reproduction of electrogenic bacteria,and is closely related to the generation of hydrogen.However,there is no specific study on the effect of different conditions on the formation and performance of MEC anode membranes.Therefore,the MEC anode membrane was cultured by the control of the key environmental factors(electrolysis voltage,initial substrate concentration,temperature and initial pH value)using acetic acid as the substrate,in order to obtain conditions for rapid culture to form MEC anode membrane having good hydrogen production performance.The experiments obtained the following concrete results:(1)Different electrolysis voltage have important impact on the formation of MEC anode membranes and membrane's hydrogen production performence.Electrolysis voltage which was applied for MEC anode membrane culture experiments were respectively set to 0.2V,0.4V,0.6V,0.8V,1.0V,1.2V,1.4V.By comparison,the electrolytic voltages that was more suitable for the acclimatization of efficient MECanode membranes were 0.6V,0.8V,1.0V,1.2V,1.4V.When the external voltage is1.0V,the current value was the largest and the hydrogen production was the highest during the formation of the MEC anode membrane process.The membranes cultured at 1.0V have the best performance of hydrogen production,the best electrochemical activity,the highest membrane biomass,and the electrolysis voltage is the most suitable electrolysis voltage condiction for accumunation MEC anode film.By analyzing the experimental data of electrolysis voltage of 0.6V ~ 1.0V,we can see that 0.52 V is the threshold voltage that is lowest voltage which can generate current under this experimental conditions.(2)The temperature has an effect on the formation of MEC anode membrane.Compared with other temperature conditions,When the temperature is 25?,35?,the circuit produced current and the system generated hydrogen.When temperature is35?,the hydrogen production performance of the anode membrane was the best,the electrochemical activity was the best,the anode membrane biomass was the highest.So it is the optimum temperature for the culture of the MEC anode membrane.(3)MEC anode membrane culture experiments were carried out at the initial substrate concentrations of 5g/L,10g/L,15g/L,20g/L,25g/L,30g/L.The MEC anode membrane with hydrogen-producing properties can be quickly formed under the conditions of 15g/L,20g/L,25g/L and 30g/L.The experimental group of the initial substrate concentration of 15g/L,20g/L,25g/L and 30g/L,can generate current and produce hydrogen.In those experimental group,it is 15g/L that the formation of the anode membrane have the best hydrogen production characteristics,the best electrochemical activity,and anode membrane biomass is the highest.For the cultivation of MEC anode membrane 15g/L is most suitable for the initial substrate concentration.(4)The initial pH has a significant effect on the formation of MEC anode membranes.In the film formation process,the experimental group of the initial initial pH of 7,8,9 can produce current.When the initial pH value are 7 and 8,the cultured anode membranes exhibited good hydrogen production characteristics,and has well electrochemical activity and phosphorus content.The initial pH value which is from 7to 8 is the most suitable for the cultivation of MEC anode membrane.(5)By analyzing the relationship between MEC anode membrane and phosphorus content,it was found that there was a linear relationship between the phosphorus content of MEC anode membrane and its electrochemical activity.The higher the electrical activity of the MEC anode film,the higher the phosphorus content,and the better the hydrogen production.