由於全球的能源危機以及環境問題日益嚴重，潔淨能源在近幾年愈被重視，而氫能源被視為具有前景的能源之一。產氫為氫能源應用之第一步驟，現今，許多熱化學反應已被應用於氫氣之生產，部分氧化反應為其中之一。部分氧化反應為一個放熱反應，其具有能被貴金數觸媒快速啟動並且無需要提供額外熱能之優點。甲醇在反應及實驗操作上的許多優點，被視為現今良好的氫氣載體。本研究探討了使用觸媒進行甲醇部分氧化於不同反應器中之氫氣的生成，共分為兩個部分。在第一部分，白金及鈀觸媒被用於噴霧系統下觸發甲醇部分氧化反應，在第二部分，瑞士捲反應器被用於白金觸媒觸發甲醇部分氧化，並提供了熱交換與預熱進料氣體之效果。
在第一部分的研究，三種低貴金屬含量 (0.2 wt%)之觸媒，Pt/Al2O3， h-BN-Pt/Al2O3及h-BN-Pd/Al2O3被用於觸發甲醇部分氧化反應，並探討氧碳比 (O2/C)對其結果之影響。由結果得知，白金觸媒可於室溫下起動甲醇部分氧化反應，而鈀觸媒則需先進行預熱。研究結果顯示，當O2/C比增加，反應溫度也隨之上升。最佳的氫氣產率為O2/C= 0.6，此結果代表了由甲醇之部分氧化到燃燒反應之轉變點。當O2/C達到0.7時，進料甲醇幾乎可以被反應消耗。整體而言，氫氣生成之效果為h-BN-Pt/Al2O3 > Pt/Al2O3 > h-BN-Pd/Al2O3，也表示了白金比起鈀觸媒具有更好的產氫效果。由熱力學分析之結果得之，理論的氫氣產率會隨著O2/C上升而下降，與本研究結果相呼應。在使用h-BN-Pt/Al2O3進行反應之結果中，實驗得到的氫氣產率與理論值相比，在O2/C= 0.8時，其值可以超過99%。然而最佳的氫氣產率為1.66 mol (mol methanol)-1，當O2/C= 0.6時，氫氣產率可以達到氫氣理論產值的91.3 %。研究中得到的結果提供甲醇部分氧化在工業中製氫之應用。
在第二部分的研究，探討瑞士捲反應器甲醇部分氧化之反應特性和性能，並將產物氣體中過量的焓轉移到反應器中進行熱交換，進而預熱進料氣體。此部分研究中，使用了h-BN-Pt/Al2O3做為觸媒於室溫下進行甲醇部分氧化反應之冷起動。研究中分為三個階段，探討了三個重要的參數，甲醇流量 (0.5 及 0.6 mL min-1)、進料氣體之氧氣濃度 (21- 35 vol%)，以及O2/C比(1.0-3.0)對甲醇部分氧化產氫效果之影響。實驗結果顯示，進料氣體可被順利地預熱，其溫度可達100 °C。第一階段結果顯示，當甲醇流量為0.5 mL min-1時，會比流量為0.6 mL min-1時具有更好之氫氣濃度與產率，當O2/C=1.0時，得到最好的氫氣濃度 (22%)，並決定了第二及第三階段之流量控制。第二階段的結果顯示，隨著進料氣體之氧氣濃度增加時，當O2/C=1.5時，得到氫氣之濃度從18.5%上升至21.8%。隨著進料氣體流速的降低，氫氣產率降低。第三階段之結果顯示，當O2/C=2.5時，具有最佳的氫氣產率1.93 mol (mol methanol)-1，而此時的氫氣濃度為23.5%。

Due to the energy crisis and the environmental issues increasingly serious, the clean energy has been emphasized in recent years. Hydrogen energy is regarded as a promising energy in the future. Producing hydrogen is the first step of hydrogen energy. There are many thermal chemical methods to produce hydrogen. Partial oxidation (POX) is a type of thermal chemical methods. POX is an exothermal reaction and it can be triggered in a fast time without any additional heating equipment by some noble-metal catalysts. Methanol is a hydrogen carrier because of many advantages for the experiment. In this research, hydrogen production by POM with catalysts is divided into two parts. In the first part, Pt and Pd catalysts are employed to trigger POM in the sprays system. In the second part, a Swiss-roll reactor is used to provide heat exchange and preheat feed gas by POM with Pt catalyst.
In the first part of this research, the hydrogen production performances of the partial oxidation of methanol (POM) under sprays are investigated. Three different catalysts of Pt/Al2O3, h-BN-Pt/Al2O3, and h-BN-Pd/Al2O3 with ultra-low Pt and Pd contents (0.2 wt%) are utilized, and the influence of the O2-to-methanol molar (O2/C) ratio on POM is examined. It is found that POM can be triggered in cold start using the Pt/Al2O3 and h-BN-Pt/Al2O3, whereas the h-BN-Pd/Al2O3 needs to be preheated to drive POM. Increasing the O2/C ratio raises the reaction temperature. The maximum H2 yield is always located at O2/C=0.6, which stands for the transition point of the chemical reaction dominated by partial oxidation to combustion. Once the O2/C ratio is 0.7, methanol is almost consumed in three catalysts. Overall, the H2 production under the aids of the catalysts is characterized by h-BN-Pt/Al2O3 > Pt/Al2O3 > h-BN-Pd/Al2O3, revealing the better performance of Pt than Pd. The thermodynamic analysis indicates that the theoretical H2 yield declines with raising the O2/C ratio, whereas the measurements suggest that the H2 production increases. For the h-BN-Pt/Al2O3 catalyst, its maximum performance, namely, the ratio of the experimental H2 yield to the theoretical one, develops at O2/C=0.8 where the value is beyond 99%. However, the maximum H2 yield of 1.66 mol (mol methanol)-1, corresponding to the performance of 91.3%, is located at O2/C=0.6 which is recommended for operation. The obtained results and findings can provide useful insights into the application of POM for hydrogen production in industry.
In the second part of this research, Methanol partial oxidation (POM) and heat recirculation in a Swiss-roll reactor are investigated experimentally. The reaction of POM in the reactor is triggered over an h-BN-Pt/Al2O3 catalyst from cold start. The effects of methanol flow rate (0.5 and 0.6 mL min-1), O2 concentration (21-35 vol%), and O2-to-methanol molar (O2/C) ratio (1.0-3.0) on the performance of POM are examined. Heat exchange by transferring the excess enthalpy in the product gas to the feed gas is achieved in the reactor where the temperature of the feed gas before entering the catalyst bed can be promoted to around 100 °C. The experimental results indicate that a methanol flow rate of 0.5 mL min-1 leads to more H2 production compared to that obtained with a flow rate of 0.6 mL min-1. In the conducted Swiss-roll reactor, oxygen supply plays an important role in accomplishing POM, and the O2/C ratio should be controlled beyond 1.0. By increasing the O2 concentration, the H2 concentration can be increased from 18.5 to 21.8% at O2/C=1.5. However, the H2 yield decreases, resulting from progressively dominant combustion mechanism. At a fixed GHSV of 10,000 h-1, the optimal O2/C ratio for H2 production is 2.5, for which the H2 concentration and H2 yield are 23.5 % and 1.93 mol (mol methanol)-1, respectively. Overall, POM along with heat recirculation in the Swiss-roll reactor can efficiently produce H2, and the excess enthalpy recovery in the reactor can improving energy utilization, thereby implementing negative emission technology.

[1] Nikolaidis P, Poullikkas A. A comparative overview of hydrogen production processes. Renewable and Sustainable Energy Reviews. 2017;67:597-611.
[2] Dispenza G, Sergi F, Napoli G, Randazzo N, Di Novo S, Micari S, et al. Development of a solar powered hydrogen fueling station in smart cities applications. International Journal of Hydrogen Energy. 2017;42:27884-93.
[3] Sakr IM, Abdelsalam AM, El-Askary WA. Effect of electrodes separator-type on hydrogen production using solar energy. Energy. 2017;140:625-32.
[4] Renkel MF, Lümmen N. Supplying hydrogen vehicles and ferries in Western Norway with locally produced hydrogen from municipal solid waste. International Journal of Hydrogen Energy. 2018;43:2585-600.
[5] Gahleitner G. Hydrogen from renewable electricity: An international review of power-to-gas pilot plants for stationary applications. International Journal of Hydrogen Energy. 2013;38:2039-61.
[6] Walker SB, Mukherjee U, Fowler M, Elkamel A. Benchmarking and selection of Power-to-Gas utilizing electrolytic hydrogen as an energy storage alternative. International Journal of Hydrogen Energy. 2016;41:7717-31.
[7] Mehmood A, Scibioh MA, Prabhuram J, An M-G, Ha HY. A review on durability issues and restoration techniques in long-term operations of direct methanol fuel cells. Journal of Power Sources. 2015;297:224-41.
[8] Chen W-H, Shen C-T, Lin B-J, Liu S-C. Hydrogen production from methanol partial oxidation over Pt/Al2O3 catalyst with low Pt content. Energy. 2015;88:399-407.
[9] Chen C-C, Tseng H-H, Lin Y-L, Chen W-H. Hydrogen production and carbon dioxide enrichment from ethanol steam reforming followed by water gas shift reaction. Journal of Cleaner Production. 2017;162:1430-41.
[10] Chen W-H, Syu Y-J. Thermal behavior and hydrogen production of methanol steam reforming and autothermal reforming with spiral preheating. International Journal of Hydrogen Energy. 2011;36:3397-408.
[11] Richards NO, Erickson PA. An investigation of a stratified catalyst bed for small-scale hydrogen production from methanol autothermal reforming. International Journal of Hydrogen Energy. 2014;39:18077-83.
[12] Pojanavaraphan C, Luengnaruemitchai A, Gulari E. Effect of support composition and metal loading on Au catalyst activity in steam reforming of methanol. International Journal of Hydrogen Energy. 2012;37:14072-84.
[13] Agrell J, Hasselbo K, Jansson K, Järås SG, Boutonnet M. Production of hydrogen by partial oxidation of methanol over Cu/ZnO catalysts prepared by microemulsion technique. Applied Catalysis A: General. 2001;211:239-50.
[14] Lytkina AA, Zhilyaeva NA, Ermilova MM, Orekhova NV, Yaroslavtsev AB. Influence of the support structure and composition of Ni–Cu-based catalysts on hydrogen production by methanol steam reforming. International Journal of Hydrogen Energy. 2015;40:9677-84.
[15] Tóth M, Varga E, Oszkó A, Baán K, Kiss J, Erdőhelyi A. Partial oxidation of ethanol on supported Rh catalysts: Effect of the oxide support. Journal of Molecular Catalysis A: Chemical. 2016;411:377-87.
[16] Hernández-Ramírez E, Wang JA, Chen LF, Valenzuela MA, Dalai AK. Partial oxidation of methanol catalyzed with Au/TiO2, Au/ZrO2 and Au/ZrO2-TiO2 catalysts. Applied Surface Science. 2017;399:77-85.
[17] Wang L, Pu C, Xu L, Cai Y, Guo Y, Guo Y, et al. Effect of supports over Pd/Fe2O3 on CO oxidation at low temperature. Fuel Processing Technology. 2017;160:152-7.
[18] Chang F-W, Roselin LS, Ou T-C. Hydrogen production by partial oxidation of methanol over bimetallic Au–Ru/Fe2O3 catalysts. Applied Catalysis A: General. 2008;334:147-55.
[19] Eichler J, Lesniak C. Boron nitride (BN) and BN composites for high-temperature applications. Journal of the European Ceramic Society. 2008;28:1105-9.
[20] Chen W-H, Shen C-T. Partial oxidation of methanol over a Pt/Al2O3 catalyst enhanced by sprays. Energy. 2016;106:1-12.
[21] Chen W-H, Chiu T-W, Hung C-I. Enhancement effect of heat recovery on hydrogen production from catalytic partial oxidation of methane. International Journal of Hydrogen Energy. 2010;35:7427-40.
[22] Chen W-H, Lin S-C. Reaction phenomena of catalytic partial oxidation of methane under the impact of carbon dioxide addition and heat recirculation. Energy. 2015;82:206-17.
[23] Shih H-Y, Huang Y-C. Thermal design and model analysis of the Swiss-roll recuperator for an innovative micro gas turbine. Applied Thermal Engineering. 2009;29:1493-9.
[24] Zhong B-J, Wang J-H. Experimental study on premixed CH4/air mixture combustion in micro Swiss-roll combustors. Combustion and Flame. 2010;157:2222-9.
[25] Lloyd SA, Weinberg FJ. Limits to energy release and utilisation from chemical fuels. Nature. 1975;257:367.
[26] Lloyd SA, Weinberg FJ. A burner for mixtures of very low heat content. Nature. 1974;251:47.
[27] Yang H-C, Chang F-W, Roselin LS. Hydrogen production by partial oxidation of methanol over Au/CuO/ZnO catalysts. Journal of Molecular Catalysis A: Chemical. 2007;276:184-90.
[28] Ubago-Pérez R, Carrasco-Marín F, Moreno-Castilla C. Methanol partial oxidation on carbon-supported Pt and Pd catalysts. Catalysis Today. 2007;123:158-63.
[29] Li C-L, Lin Y-C. Methanol partial oxidation over palladium-, platinum-, and rhodium-integrated LaMnO3 perovskites. Applied Catalysis B: Environmental. 2011;107:284-93.
[30] Schuyten S, Guerrero S, Miller JT, Shibata T, Wolf EE. Characterization and oxidation states of Cu and Pd in Pd–CuO/ZnO/ZrO2 catalysts for hydrogen production by methanol partial oxidation. Applied Catalysis A: General. 2009;352:133-44.
[31] Bake H, Zaman SF, Alhamed YA, Al-Zahrani AA, Daous MA, Rather SU, et al. Partial oxidation of methanol over Au/CeO2-ZrO2 and Au/CeO2-ZrO2-TiO2 catalysts. RSC Advances. 2016;6:22555-62.
[32] Agrell J, Germani G, Järås SG, Boutonnet M. Production of hydrogen by partial oxidation of methanol over ZnO-supported palladium catalysts prepared by microemulsion technique. Applied Catalysis A: General. 2003;242:233-45.
[33] Jiang TL, Chen WS, Tsai MJ, Chiu HH. A numerical investigation of multiple flame configurations in convective droplet gasification. Combustion and Flame. 1995;103:221-38.
[34] Wang F, Zhang D, Zheng S, Qi B. Characteristic of cold sprayed catalytic coating for hydrogen production through fuel reforming. International Journal of Hydrogen Energy. 2010;35:8206-15.
[35] Kang HW, Park SB. Doping of fluorine into SrTiO3 by spray pyrolysis for H2 evolution under visible light irradiation. Chemical Engineering Science. 2013;100:384-91.
[36] Chen W-H. Unsteady absorption of sulfur dioxide by an atmospheric water droplet with internal circulation. Atmospheric Environment. 2001;35:2375-93.
[37] Chen W-H, Cheng Y-C, Hung C-I. Transient reaction and exergy analysis of catalytic partial oxidation of methane in a Swiss-roll reactor for hydrogen production. International Journal of Hydrogen Energy. 2012;37:6608-19.
[38] Kim NI, Kato S, Kataoka T, Yokomori T, Maruyama S, Fujimori T, et al. Flame stabilization and emission of small Swiss-roll combustors as heaters. Combustion and Flame. 2005;141:229-40.
[39] Chein R-Y, Chen Y-C, Chang C-M, Chung JN. Experimental study on the performance of hydrogen production from miniature methanol–steam reformer integrated with Swiss-roll type combustor for PEMFC. Applied Energy. 2013;105:86-98.
[40] Tsai B-J, Wang YL. A novel Swiss-Roll recuperator for the microturbine engine. Applied Thermal Engineering. 2009;29:216-23.
[41] Aziznia A, Oloman CW, Gyenge EL. A Swiss-roll liquid–gas mixed-reactant fuel cell. Journal of Power Sources. 2012;212:154-60.
[42] Chen W-H, Cheng Y-C, Hung C-I. Enhancement of heat recirculation on the hysteresis effect of catalytic partial oxidation of methane. International Journal of Hydrogen Energy. 2013;38:10394-406.
[43] Chen W-H, Cheng Y-C, Hung C-I. Entropy generation from hydrogen production of catalytic partial oxidation of methane with excess enthalpy recovery. International Journal of Hydrogen Energy2012. p. 14167-77.
[44] Chen W-H, Chiu T-W, Hung C-I. Hydrogen production from methane under the interaction of catalytic partial oxidation, water gas shift reaction and heat recovery. International Journal of Hydrogen Energy. 2010;35:12808-20.
[45] Mane Deshmukh SB, Krishnamoorthy A, Bhojwani VK. Experimental Research on the Effect of Materials of One Turn Swiss Roll Combustor on Its Thermal Performance as a Heat Generating Device. Materials Today: Proceedings. 2018;5:737-44.
[46] Chen W-H, Guo Y-Z. Hydrogen production characteristics of methanol partial oxidation under sprays with ultra-low Pt and Pd contents in catalysts. Fuel. 2018;222:599-609.
[47] Jacobsen CJH. Boron Nitride: A Novel Support for Ruthenium-Based Ammonia Synthesis Catalysts. Journal of Catalysis. 2001;200:1-3.
[48] Kostoglou N, Polychronopoulou K, Rebholz C. Thermal and chemical stability of hexagonal boron nitride (h-BN) nanoplatelets. Vacuum. 2015;112:42-5.
[49] Chen W-H, Jheng J-G, Yu AB. Hydrogen generation from a catalytic water gas shift reaction under microwave irradiation. International Journal of Hydrogen Energy. 2008;33:4789-97.
[50] Lebarbier V, Dagle R, Datye A, Wang Y. The effect of PdZn particle size on reverse-water–gas-shift reaction. Applied Catalysis A: General. 2010;379:3-6.
[51] Chen W-H, Lin B-J. Hydrogen and synthesis gas production from activated carbon and steam via reusing carbon dioxide. Applied Energy. 2013;101:551-9.
[52] Tong GCM, Flynn J, Leclerc CA. A dual catalyst bed for the autothermal partial oxidation of methane to synthesis gas. Catalysis Letters. 2005;102:131-7.
[53] Kapoor MP, Ichihashi Y, Shen W-J, Matsumura Y. Catalytic Activity of Palladium Supported on Mesoporous Zirconium Oxide in Low-Temperature Methanol Decomposition. Catalysis Letters. 2001;76:139-42.
[54] Nematollahi B, Rezaei M, Khajenoori M. Combined dry reforming and partial oxidation of methane to synthesis gas on noble metal catalysts. International Journal of Hydrogen Energy. 2011;36:2969-78.
[55] Chen W-H, Jheng J-G. Characterization of water gas shift reaction in association with carbon dioxide sequestration. Journal of Power Sources. 2007;172:368-75.
[56] Xu G, Chen X, Zhang Z-G. Temperature-staged methanation: An alternative method to purify hydrogen-rich fuel gas for PEFC. Chemical Engineering Journal. 2006;121:97-107.
[57] Chen C-H, Ronney PD. Three-dimensional effects in counterflow heat-recirculating combustors. Proceedings of the Combustion Institute. 2011;33:3285-91.
[58] Cubeiro ML, Fierro JLG. Partial oxidation of methanol over supported palladium catalysts. Applied Catalysis A: General. 1998;168:307-22.
[59] Pal DB, Chand R, Upadhyay SN, Mishra PK. Performance of water gas shift reaction catalysts: A review. Renewable and Sustainable Energy Reviews. 2018;93:549-65.
[60] Ascaso S, Elena Gálvez M, Da Costa P, Moliner R, Lázaro Elorri MJ. Influence of gas hourly space velocity on the activity of monolithic catalysts for the simultaneous removal of soot and NOx. Comptes Rendus Chimie. 2015;18:1007-12.
[61] Deng J, Li Q, Xiao Y, Wen H. The effect of oxygen concentration on the non-isothermal combustion of coal. Thermochimica Acta. 2017;653:106-15.
[62] Engin B, Atakül H. Air and oxy-fuel combustion kinetics of low rank lignites. Journal of the Energy Institute. 2018;91:311-22.