Hydrogen is a relevant purpose that South Africa sets as priority of renewable technologies in a bid to reduce the country’s oil and gas dependence and consequently reduction of its heavily carbon emission. Possessor worldwide of almost 75% of the platinum, South Africa sees the opportunity to play a new role in decades coming with the development of hydrogen economy highlighting positive impacts in socio-economical and ecological aspects. Platinum is a best catalyst metal to be used as electrode to the production of hydrogen by water electrolysis with no carbon emission. This paper examines the sustainability and technological development of hydrogen production for fuel cells technologies processes, the input-output energy comparison involved by utilizing life cycle inventories in which the energy and raw material consumption and different types of emissions related to a specific product are measured, analyzed and summoned over the life cycle’s entire products from an environmental viewpoint

Mabiza, J.

Mbohwa, Charles

English

University of Johannesburg Institutional Repository

P-001EcoBalance2010The 9th International Conference on EcoBalanceNovember 9-12, 2010, Tokyo, Japan Eco-vision Aspect and Sustainable Development through Hydrogen Economy in South Africa J. Mabiza1,* and C. Mbohwa21University of Johannesburg, jmabiza2008@hotmail.fr2University of Johannesburg, cmbohwa@uj.ac.za* jmabiza@uj.ac.zaAbstractHydrogen is a relevant purpose that South Africa sets as priority of renewable technologies in a bid to reduce the country’s oil and gas dependence and consequently reduction of its heavily carbon emission. Possessor worldwide of almost 75% of the platinum, South Africa sees the opportunity to play a new role in decades coming with the development of hydrogen economy highlighting   positive impacts in socio-economical and ecological aspects. Platinum is a best catalyst metal to be used as electrode to the production of hydrogen by water electrolysis with no carbon emission. This paper examines the sustainability and technological development of hydrogen production for fuel cells technologies processes, the input-output energy comparison involved by utilizing life cycle inventories in which the energy and raw material consumption and different types of emissions related to a specific product are measured, analyzed and summoned over the life cycle’s entire products from an environmental viewpoint.   Keywords: Hydrogen, electrolysis, Platinum nanophase electro catalysts composites electrodes, Life Cycle Inventories.    1. Introduction The entire and complete project of hydrogen economy is technologically based on the elaboration and production of main components among which the development of platinum electrodes, development of membranes insulators and conductors of different electro kinetic particles such as electron and proton, development of electrolysis environment, production of hydrogen gas by water electrolysis, storage medium and fuel cells. This work was focused on the development of life cycle inventories of the platinum nanophase electro catalysts composites electrode process resulted from the experiment developed in South Africa [3]. The basic initiative for the experimentation had invested on the assumption stating that if high current densities could be obtained for a low energy input and particularly with low electrolyte environments using renewable energy with a strong emphasis upon waste reduction and reuse among environmental impacts as well as the use of platinum electro catalyst nanophase integrated into composite electrodes, it could result a commercialization potential [3]. Besides, Umberto 5.5 consult version software was used to develop flows charts, Input-output and Life cycle Inventories balance sheets respectively for both Hexagonal Mesoporous Silica (HMS) material and the platinum nanophase electro catalysts composites electrode. Platinum nanophase was supported upon the mesoporous HMS by incipient wetness impregnation. The HMS is not commercially available and the synthesis was obtained according to standard methods done by Tanev and Pinnavaia described by Kwang [2]. 2. Objective The aim of this work was inspired from the purpose of the conference to use Life Cycle Inventories and Assessment tools to analyze processes developed with new technologies with a focus on environmental impacts and effective benefit on the energy as well. 3. Scope The study was limited for modeling Input-Output and Life Cycle Inventories flow charts and balance sheets respectively for the HMS material synthesis and the platinum nanophase electro catalysts composites electrode synthesis, obtained from experiment processes. P-001EcoBalance2010The 9th International Conference on EcoBalanceNovember 9-12, 2010, Tokyo, Japan 4. Results and discussion 4.1 Balance sheets Table 1: Hexagonal Mesoporous Silica. Balance sheet Preview from Umberto. 4.2 Flow charts 4.2.1 Preparation of Hexagonal Mesoporous Silica (HMS) Fig.1 Flow charts for the elaboration of HMS. Table 2: Platinum nanophase electro catalyst HMS impregnated.  Balance sheet Preview from Umberto.             Balance sheet Preview Project    : Platinum nanophase synthesis Scenario : Pt nanophase HMS impregnated Net           : Main Section    : Life Cycle Invetories Group      : Material Reference Flow: Pt-HMS heated (Output, A31) Quantity  : 0.02577 Kg  Input Item Quantity Unit G Deionized water 0.016674 Kg G Electricity 7557655.705885 KJ G Formaldehyde 0.001458 KJ G HMS 0.001375 Kg G Methanol 0.000742 Kg G Methanol/formaldehyde sln 0.006000 Kg G PtCl6.6H2O 0.001296 Kg Sum Quantity Unit KJ 17457558.705885 KJ Kg 0.027545 Kg  Output Item Quantity Unit B Formaldehyde toxic emission 1.37651 Kg B Heat emitted 1513363.43896 Kg B Methane toxic-emission 1.37565 E-6 Kg B Methanol/Formaldehyde citotoxicity  0.00171 Kg G Pt-HMS heated 0.02577 Kg B Pt-HMS solid waste 6 E-5 Kg Sum Quantity Unit KJ 1513363.43896  Kg 0.02754 Kg Balance sheet Preview Project    : Hexa Mesoporous Silica (HMS) Scenario : HMS production Net           : Main Section    : Input/output Group      : Material  Input Item Quantity Unit G 1-Dodecylamine (C12H27N) 0.0100 Kg G Deionized water 0.8000 Kg G Electricity 17314998.0672 KJ G Electricity (En. to stir) 142560.0000 KJ G Ethanol (EtOH) 0.1050 Kg G TEOS (Si(OC2H5)4) 0.4460 Kg G Water (H2O) 0.1067 Kg Sum Quantity Unit KJ 17457558.0672 KJ Kg 1.4677 Kg  Output Item Quantity Unit G Ethanol (EtOH) 0.5000 Kg B Gas emission 0.0099 Kg G HMS 0.0901 Kg B Wastewater 0.8677 Kg Sum Quantity Unit Kg 1.4677 Kg P1:Raw materialP2:Auxiliairy materialP3:Solid      ProductT1:Mixture      stirringT2:filtering,      rinsing P6:WasteP7:Solid Product, purified      and drying airT3: Soxhlet      Extractor. P5:Pale yellow solidP8:EmissionsP2:Auxiliairy materialT4:drying at80°C for 3hP9:Pale yellow solidT5:heatingrate 2 °C/min.630°C for 4hP10: HMSProduction of Hexagonal Mesoporous SilicaP11: Raw materialP4:Waste P12: Emissions4.2.2 Preparation of HMS-Platinum nanophase electro catalysts composite electrode           Fig.1 Flow charts for the elaboration of Pt-HMS impregnated. 5. Interpretation of results On basis of experiments, developed flow charts were established through Umberto 5.5. – In which were described processes and quantified data. Sources such as internet, chemistry and physics published articles were used to determine different type of emissions in accordance with chemical reactions applied. Stored modules predefined in the software database library, where modules of materials have been predefined with their respective types of emissions, were not utilized for most of the materials were not therein found. The waste of electric energy as heat emitted and toxic emissions from formaldehyde and methane were observed. Major environmental impacts were not noticed. The input-output energy comparison was assessed with reference to the result from the experiment thence was established as follow the incorporating supported platinum nanophase electro catalysts in composite electrodes resulted in production of electrodes capable of current densities for hydrogen production by water electrolysis of about 600mAcm 2 at 60 C at an applied potential of 2V in a high electrolyte environment and most, the fact that the electrodes were able to withstand the very high degree of hydrogen gas evolution at an applied potential of 6V showed that even under these aggressively accelerated testing conditions the nanophase catalyst containing thin films were stable and durable [3].     6. Conclusion  As known, the hydrogen gas for the purpose to fuel cells development stands for no carbon emission. On the other hand the upstream development composites tools for hydrogen production with electrolysis of water such as electrodes and specially for this experiment with the platinum nanophase electro catalysts electrodes composite had to be investigated whether it offers pollution emissions and in which proportion. The analysis was assessed with the use of Life Cycle Inventories tools. Furthermore, the effective benefit of the energy in the hydrogen gas production with platinum nanophase electro catalyst composite electrode was investigated with success by the application in a high electrolyte environment. 7. References [1] Cassiers, K., Van Der Voort , P., & Vansant, E. F., Synthesis of stable and directly usable hexagonal mesoporous silica by efficient amine extraction in acidified water, The Royal Society of Chemistry 2000, Chem. Commun, 2489–2490, 2000. [2] Kwang, Y. K., Sung, T. P., & Myoung, J. C., Deprotection of Acetals and Ketals over Hexagonal Mesoporous Molecular Sieve as a Reusable, Heterogeneous Catalyst, Bulletin of the Korean chemical society, ISSN 0253-2964.Volume 21, 2000, Number 10. [3] Petrik, L.F., Godongwana, Z.G., & Iwuoha, E.I, Platinum nanophase electro catalysts and composite electrodes for hydrogen production, Journal of Power Sources, 185, 2008, 838–845. [4] Rinsland, C.P., Dufour, G., Szopa, S., Hauglustaine, D. A., Boone, C. D., and Bernath, P. F., The influence of biogenic emissions on upper-tropospheric methanol as P1:Raw materialT1:H2PtCl6·6H2O Acid solution synthesizedT2:HMS  impregnated with PtP3:Pt-HMS     impregnated T3:Methanol/Formaldehyde      synthesisP4:Methanol/Formaldehyde      solutionHexagonal Mesoporous impregnated with Platinum Methanol/Formaldehyde solution synthesisT4:Pt seeding procedure by submerging Pt-HMS in M/F sln P5:Slurry      Pt-HMS impregnated M/FT5:Drying     100°C, 60'P6:Auxliairy Material:    ElectricityP7:Pt-HMS dried T6: Pt-HMS seeding procedure by submerging inM/F sln; 24hP8:air emissions,      toxicity on exposure P9:Heat:air emissions and citotoxicity emissionsP10:Slurry        Pt-HMST7:Drying    32°C, 24hP11P12: Auxliairy Material:    ElectricityP13:Heat: air emissions   and citotoxicity emissionsT8:Heating     100°C, 60'P14P15:Heat: air emissionsand  citotoxicity emissionsT9:Filtering     rinsingP17: Pt-HMS: soil emissionP16 T10 P18:Pt-HMS heated         Out/put        P15:Heat: air emissionsand  citotoxicity emissionsP19:Methanol/Formaldehyde      solutionP20:Raw MaterialP21:Raw materialP2HMS - PLATINUM NANOPHASE ELECTRO CATALYSTS IMPREGNATED  COMPOSITES ELECTRODEP-001EcoBalance2010The 9th International Conference on EcoBalanceNovember 9-12, 2010, Tokyo, Japan 4.2.2 Preparation of HMS-Platinum nanophase electro catalysts composite electrode           Fig.1 Flow charts for the elaboration of Pt-HMS impregnated. 5. Interpretation of results On basis of experiments, developed flow charts were established through Umberto 5.5. – In which were described processes and quantified data. Sources such as internet, chemistry and physics published articles were used to determine different type of emissions in accordance with chemical reactions applied. Stored modules predefined in the software database library, where modules of materials have been predefined with their respective types of emissions, were not utilized for most of the materials were not therein found. The waste of electric energy as heat emitted and toxic emissions from formaldehyde and methane were observed. Major environmental impacts were not noticed. The input-output energy comparison was assessed with reference to the result from the experiment thence was established as follow the incorporating supported platinum nanophase electro catalysts in composite electrodes resulted in production of electrodes capable of current densities for hydrogen production by water electrolysis of about 600mAcm 2 at 60 C at an applied potential of 2V in a high electrolyte environment and most, the fact that the electrodes were able to withstand the very high degree of hydrogen gas evolution at an applied potential of 6V showed that even under these aggressively accelerated testing conditions the nanophase catalyst containing thin films were stable and durable [3].     6. Conclusion  As known, the hydrogen gas for the purpose to fuel cells development stands for no carbon emission. On the other hand the upstream development composites tools for hydrogen production with electrolysis of water such as electrodes and specially for this experiment with the platinum nanophase electro catalysts electrodes composite had to be investigated whether it offers pollution emissions and in which proportion. The analysis was assessed with the use of Life Cycle Inventories tools. Furthermore, the effective benefit of the energy in the hydrogen gas production with platinum nanophase electro catalyst composite electrode was investigated with success by the application in a high electrolyte environment. 7. References [1] Cassiers, K., Van Der Voort , P., & Vansant, E. F., Synthesis of stable and directly usable hexagonal mesoporous silica by efficient amine extraction in acidified water, The Royal Society of Chemistry 2000, Chem. Commun, 2489–2490, 2000. [2] Kwang, Y. K., Sung, T. P., & Myoung, J. C., Deprotection of Acetals and Ketals over Hexagonal Mesoporous Molecular Sieve as a Reusable, Heterogeneous Catalyst, Bulletin of the Korean chemical society, ISSN 0253-2964.Volume 21, 2000, Number 10. [3] Petrik, L.F., Godongwana, Z.G., & Iwuoha, E.I, Platinum nanophase electro catalysts and composite electrodes for hydrogen production, Journal of Power Sources, 185, 2008, 838–845. [4] Rinsland, C.P., Dufour, G., Szopa, S., Hauglustaine, D. A., Boone, C. D., and Bernath, P. F., The influence of biogenic emissions on upper-tropospheric methanol as P1:Raw materialT1:H2PtCl6·6H2O Acid solution synthesizedT2:HMS  impregnated with PtP3:Pt-HMS     impregnated T3:Methanol/Formaldehyde      synthesisP4:Methanol/Formaldehyde      solutionHexagonal Mesoporous impregnated with Platinum Methanol/Formaldehyde solution synthesisT4:Pt seeding procedure by submerging Pt-HMS in M/F sln P5:Slurry      Pt-HMS impregnated M/FT5:Drying     100°C, 60'P6:Auxliairy Material:    ElectricityP7:Pt-HMS dried T6: Pt-HMS seeding procedure by submerging inM/F sln; 24hP8:air emissions,      toxicity on exposure P9:Heat:air emissions and citotoxicity emissionsP10:Slurry        Pt-HMST7:Drying    32°C, 24hP11P12: Auxliairy Material:    ElectricityP13:Heat: air emissions   and citotoxicity emissionsT8:Heating     100°C, 60'P14P15:Heat: air emissionsand  citotoxicity emissionsT9:Filtering     rinsingP17: Pt-HMS: soil emissionP16 T10 P18:Pt-HMS heated         Out/put        P15:Heat: air emissionsand  citotoxicity emissionsP19:Methanol/Formaldehyde      solutionP20:Raw MaterialP21:Raw materialP2HMS - PLATINUM NANOPHASE ELECTRO CATALYSTS IMPREGNATED  COMPOSITES ELECTRODEP-001EcoBalance2010The 9th International Conference on EcoBalanceNovember 9-12, 2010, Tokyo, Japan revealed from space, http://www.atmos-chem-phys discuss.net/7/9183/2007/acpd-7-9183-2007.pdf, (Accessed 17/08/2010). [5] Wikipedia, Formaldehyde, http://en.wikipedia.org/wiki/Formaldehyde, (Accessed 25/07/2010). 

Eco-vision aspect and sustainable development through hydrogen economy in South Africa

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Eco-vision aspect and sustainable development through hydrogen economy in South Africa

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