Thermodynamic Calculation And Analysis Of Hydrogen Production Process From Ethanol Reforming And Catalyst Selection

Hydrogen is a clean energy, has merits of high heat of combustion, non-airpollution, easy to store and transport, it can be used as a substitute for future energy.Ethanol is widely used as a feedstock for hydrogen production for wide sources, lesstoxicity, easy to store and transport, environmentally friendly. This paper researchhydrogen amount from ethanol reforming hydrogen production mainly from twodirections of phase state and catalyst. Analysis the change of the reaction productswhen reaction in different phase taken temperature, pressure, ratio of water tomethanol as key factor and creening catalyst according to the conditions of reforming.This paper analysis ethanol reforming hydrogen production from the aspect ofthermodynamic on the basis of the principle of the Gibbs free energy minimizationmethod. The research of hydrogen production from ethanol reforming while water wasin gas phase was through the establishment of a simple model of hydrogen productionby steam reforming of ethanol then analysed the ways that how to gain the modelparameters. Analysed variation tendency of main product (hydrogen, carbon, carbonmonoxide) with critical factors when the reaction reach thermodynamic equilibrium bythe Mathcad software. The results show that ethanol equilibrium conversion ratereached almost100%; hydrogen yield increases with temperature and ratio of water tomethanol increasing while decreases as the pressure rising gradually. As the ratio ofwater-ethanol increased unlimited, producing hydrogen capacity significantly increased first, and eventually change slowly, infinite close to6(ethanol for1mol);lower temperature and higher pressure inhibition effect on the CO produced; lowwater-ethanol can lead to serious carbon deposition. Then considered water as liquidphase, the simulated calculation of hydrogen production from ethanol reforming foundthat: hydrogen production quantity increases with temperature rise, and decreases withincrement of the pressure and it has weak correlation with ratio of water-alcohol, Effectof liquid phase reforming hydrogen production is less than the effect of the gas phase.Conclusions are consistent when comparing the calculation results of this paper andother scholar’s research results.Catalyst plays an important role in reducing cost and improving the reaction rateof ethanol reforming hydrogen production, this paper analyze the influence ofthe catalyst of hydrogen from the angle of the ethanol reforming reaction, the resultsof screening for comparing is following: the catalytic performance ofRh/CeO2catalyst in the precious metal is better than that of Rh/Al2O3; when thetemperature is lower than723K, the bimetallic catalyst Rh-Ni/CeO2can promote theproduct of hydrogen from ethanol reforming better. Co/MgO is more suitable thanCo/Al2O3to promote the ethanol reforming reaction than other non noblemetal catalyst; under the condition of low temperature, Ni/La2O3has the overall bestperformance in the Ni catalyst supported. ZnO has better hydrogen activity and highselection in the oxide catalyst.Using mathcad software, this paper studies the effect of the phase state of wateron the performance of hydrogen production from ethanol reforming and screening ofcatalyst, which provides a new method of numerical simulation and theoretical basisfor subsequent ethanol theory research, having a certain guiding significance.