Microbial fuel cell.ppt

1、Lixiaojia Wangmancang,Microbial Fuel Cell-MFC （微生物燃料電池）,Contents,Definition of MFC,Introduction of MFC,Definition of MFC,MFC are bioelectrical devices that harness the natural metabolisms(新陳代謝) of microbes to produce electrical power directly from organic material.,chemical energy -electrical energy

2、,bacteria,metabolism,Contents,Definition of MFC,Introduction of MFC,Background of MFC,Environmental problems,MFC,Introduction of MFC,Energy crisis,Development course of MFC,After 2002,1980s,1960s,Early days,Introduction of MFC,(中介),（發(fā)酵）,（蓄電池）,classified of MFC,Introduction of MFC,Soil-based MFC （土壤為

3、底物）,Wastewater-based of MFC (污水為底物),（陽極生物膜）,（質(zhì)子交換膜）,（陽極）,（陰極）,（陰極電解質(zhì)）,external circuit （外電路）,Anodic compartment (陽極室),Cathodic compartment(陰極室),(負載),bacteria,Wastewater-based MFC,cathode（陰極）,anode （陽極）,Introduction of MFC,plexiglass （有機玻璃）,incubator(培養(yǎng)箱),Soil-based MFC,In this structure, a biofilm w

4、ill spontaneously(自發(fā)的) develop on the anode surface over time resulting in power generation.,Introduction of MFC,Soil-based MFC,Soil is full of complex sugars and other nutrients that have accumulated over millions of years of plant and animal material decay, so there is plenty of food for the micro

5、bes to thrive for years.,Introduction of MFC,the chemical reaction,anode：oxidation process（氧化過程） (CH2O)nnH2O nCO24ne-4nH+,Introduction of MFC,the chemical reaction,cathode：reductive process（還原過程） 4e-O24H+ 2H2O,Introduction of MFC,Contents,Definition of MFC,Introduction of MFC,General principles of M

6、FC,General principles of Wastewater-based MFC,H+,e-,e-,e-,e-,(CH2O)nnH2O nCO24ne-4nH+,4e-O24H+ 2H2O,H+,General principles of Soil-based MFC,e-,e-,e-,e-,e-,H+,H+,Anode:,solid graphite （石墨）,graphite-felt（石墨氈）,carbon cloth（碳布）,Materials,Function: concentrate the bacteria and transfer electrons.,Cathode

7、,cathode, as an electron acceptor, oxygen is reduced to water here. To obtain a sufficient oxygen reduction reaction (氧還原) rate a Platina-catalyst（鉑催化劑） has to be used.,PEMproton exchange membrane（質(zhì)子交換膜）,separates the anode from the cathode plays the role of an electric insulator（絕緣體）and allows prot

8、ons to move through,The fuel in the anode compartment,Wastewater: carbohydrates volatile fatty acids (揮發(fā)性脂肪酸) alcohols (醇類) sulfides(硫化物) amino acids, proteins ,soil: complex sugars and other nutrient,The bacteria-key player,Shewanella (希瓦氏菌),Known for their versatility, they can be found almost eve

9、rywhere on earth, from mountain soils, to ocean sediments(沉積物).,The bacteria-key player,Shewanella (希瓦氏菌),They have an ability to metabolize（新陳代謝） wide variety of elements that are toxic to humans, yet they dont cause disease in humans.,The bacteria-key player,Shewanella (希瓦氏菌),They even have the ab

10、ility to metabolize(新陳代謝)radioactive uranium（放射性鈾）, precipitating(沉淀) it out of contaminated（受污染的） waters.,The bacteria-key player,Geobacter （地桿菌屬）,Known as the “iron-breather”, they have the ability to “inhale”（吸入） iron compounds and use them in a way similar to the way humans use oxygen.,The bacte

11、ria-key player,Geobacter （地桿菌屬）,In fact, they prefer to live in environments where there is no oxygen, such as deep underground or within ocean sediments(沉積物).,The bacteria-key player,Geobacter （地桿菌屬）,They have the ability to consume many environmental pollutants, including petroleum（石油） and uranium

12、（鈾）, and have been used in many soil and water bioremediation(生物修復(fù)) efforts.,The ways of electron transfer mechanisms:,In the membrane,Out of the membrane,The ways of electron transfer mechanisms:,The figure shows the orientation of the electron carriers (electron transfer chain) and the electron tr

13、ansport in the membrane of a model prokaryote(原核生物). Whereas: FMN(黃素蛋白) FAD（黃素腺嘌呤二核苷酸） Q: quinone（醌）, Fe/S: iron sulfur protein（鐵硫蛋白） cyt a, b, c（細胞色素）,Respiratory chain (呼吸鏈),The ways of electron transfer mechanisms:,1.Direct Transfer: Direct transfer from the microbes cell membrane to the anode su

14、rface .,The ways of electron transfer mechanisms:,2Electron Shuttling(穿梭) Employing a secondary biomolecule to shuttle the electron to the anode.,The ways of electron transfer mechanisms:,3. Nanowires（納米線） Transferring the electron through conductive （導(dǎo)電的）appendages（附加物）, termed “nanowires”, grown b

15、y the bacteria.,Contents,Definition of MFC,Introduction of MFC,General principles of MFC,Advantages and problems of MFC,Advantages of MFC,Biocompatibility（生物相容性）;,Environment-friendly ：no acid, heavy metals and other pollutants generated;,The sructure is relatively simple;,Wide range of materials;,Mild operating conditions;,Problems of MFC-low power outputs,MFCs output voltage is basically stable at about 325 mV,（電壓）,Voltage changes with time and fuel,adding fuel,Conten