INSTITUTUL NAŢIONAL DE CERCETARE DEZVOLTARE PENTRU TEHNOLOGII IZOTOPICE SI MOLECULARE Str. Donat 67-103, 400293, Cluj-Napoca, Romania Tel: +40-264-584037; Fax: +40-264-420042 Email: itim@itim-cj.ro, web: www.itim-cj.ro

 

 

 

 

 

 

 

 

Design by MM

             Deadline: december 2012

Title of Phase 1: General assessment of the catalytic production of hydrogen from renewable oxygenates: catalysts preparation and characterization; evaluation of ethanol and glycerol steam reforming processes for hydrogen production in terms of thermodynamic aspects, conceptual layout; optimization of bioethanol preparation method from wood waste; possibilities of energetic valorization of glycerol.
Results: (1)  thermodynamic study of hydroxylic compounds steam reforming; (2)  bio-ethanol production method from wood wastes; (3)  samples of bio-ethanol; (4)  method for preparation and characterization of Ni-Me/oxide1-oxide2 catalysts; (5)  samples of Ni-Me/oxide1-oxide2 catalysts (Me = Cu, Au, Ag; oxide1 =  CeO2, La2O3, oxide2 = Al2O3, ZrO2) full characterized; (6)  scientific and technological report containing the experimentation reports for bio-ethanol production and catalysts characterization, scientific report for theromodinamic study of ethanol steam reforming and a literature survey for possible applications of waste crude glycerol.	Dissemination: - 1 accepted paper; - 2 papers at international conferences; - 2 accepted papers at international conferences. (see papers)
(1) Due to their high content of carbohydrates, the wood wastes are recommended as proper raw materials for the production of bio-ethanol. In this stage of the project, two methods for the production of ethanol from wood wastes were experimented chemical hydrolysis and enzymatic hydrolysis. The higher yield for chemical hydrolysis was 70% and was obtained for acid hydrolysis of wood waste self-hydrolyzed at 190°C, 10 barr pressure and 10 minutes reaction time. For enzymatic hydrolysis the higher yield was 90% and was obtained for wood wastes pre-treated at  190°C and hydrolyzed with Accellerase 1500. The different composition of the fermentation environment in case of the two studied methods influences the production of bio-ethanol. (2) The thermodynamic study, made with the ChemCAD process simulator, evidenced that during the ethanol steam reforming process, a series of side reactions can occur, which lead to several by-products: CO, CH4, CH3CHO, C2H4, etc. Our results indicated that at low temperatures CH4 is an important product, while at elevated temperatures the H2 formation is favored. Hydrogen maximum concentration of about 70-75 mol. % is obtained at temperatures higher than 600°C. The increasing of molar ratio H2O/ethanol favors the H2 production, which is in our advantage taking into account the low ethanol concentration in brute bio-ethanol. The thermodynamic analysis indicated that the concentration of by-products can be lowered by working at low pressures and high H2O/ethanol ratio. (3) Two series of Ni based catalysts were prepared and characterized: (1) Ni/Al2O3 modified by addition of group Ib metals; (2) catalyst supports modified by addition of cerium oxide or lanthanum oxide. For the preparation of nickel based catalysts, to be used for ethanol steam reforming experiments, two preparation methods were chosen: co-impregnation and successive impregnation. The catalysts characterization methods – BET, hydrogen chemisorption, X-ray diffraction, electronic microscopy – showed that the promoted Ni based catalysts have structural characteristics which recommend them as efficient heterogeneous catalysts. In this respect: (i) the prepared catalysts have a mesoporous structure with total surface area of tens of m2/g; (ii) the nickel nanoparticles have 10-20 nm size and are uniformly distributed on the support; (iii) the addition of metals – Cu, Ag, Au – and oxides – CeO2, La2O3  – leads to a better dispersion of Ni nanoparticles on the support.