本實驗研究了鹼金屬碳酸鹽摻雜之氧化鎂粉體的製備。由於氧化鎂顆粒表面的自然基本強度且其效能被其形貌、表面積、表面結構所掌控，氧化鎂是個有潛力的吸附劑，可以捕捉二氧化碳。然而，商用氧化鎂的吸收能力很低，在300 oC下只有0.04 mmol/g，添加鹼金屬碳酸鹽（碳酸銫）後可展現其吸附能力，同時，超音波噴霧熱裂解被用於合成碳酸銫摻雜的氧化鎂粉體。藉由醋酸鎂製備氧化鎂粉體作為母體，而碳酸銫則作為摻雜物的來源。藉由X光繞射儀與熱重分析儀分析粉體的吸附情形，利用氮氣吸/脫附分析儀量測比表面積，使用掃描式電子顯微鏡與穿透式電子顯微鏡觀察粉體的形貌。分析結果顯示碳酸銫沉積於氧化鎂表面展現了比未摻雜的氧化鎂或商用氧化鎂更高的二氧化碳吸附能力，最理想的銫濃度為20 molar%，且其成功達到每公克吸附1.4 mmol的二氧化碳，不規則形狀的粉體顆粒與混和的鎂銫化合物碳酸鹽的相則被發現可改善碳酸銫摻雜之氧化鎂的吸附能力。本實驗顯示當銫不均勻的散布於氧化鎂的母體時，可以達到較高的二氧化碳吸附量。

This study reported the fabrication of alkali-metal carbonates doped MgO powder. MgO itself is a promising adsorbent to capture CO2 due to its natural basic strength on the surface of the particle and its performance is well controlled by its morphology, surface area and surface structure. However, commercial MgO has very low sorption ability of 0.04 mmol/g sorbents at 300oC. Addition of alkali-metal carbonates (Cs2CO3) has been shown to exhibit the adsorption capacities. Ultrasonic spray pyrolysis was conducted to synthesize Cs2CO3 doped MgO powder simultaneously. As the matrix, MgO powder was prepared from Mg(CH3COO)2.4H2O precursor and Cs2CO3 were prepared as the dopant source. The adsorbent was characterized using X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA) and N2 adsorption desorption (BET) to measure the specific surface area. The morphology of the particle was observed using scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). Based on these characterizations, it was shown that Cs2CO3 deposition on MgO surface exhibit higher CO2 adsorption capacity than undoped MgO and/or commercial MgO. The optimum concentration of Cs loading is 20 molar% Cs which successfully achieved 1.4 mmol CO2 per gram sorbents. Irregular shape particle and mixed compound of magnesium – cesium carbonate phase has been found to be responsible for the improvement of sorption capacity of the Cs2CO3-doped MgO powder. To the best of our findings, it is suggested that higher CO2 sorption can be achieved if cesium is uniformly dispersed throughout MgO matrix.

References
[1] C.M. Branch, S. Scientist, M. Office, H. Centre, J. Richter-menge, State of the Climate in 2012, 2012.
[2] M. Liu, C. Vogt, S.L.Y. Chang, Nanoscale Structural Investigation of Cs2CO3 Doped MgO Sorbent for CO2 Capture at Moderate Temperature, (2013).
[3] H. Lund, B. V. Mathiesen, Energy system analysis of 100% renewable energy systems-The case of Denmark in years 2030 and 2050, Energy. 34 (2009) 524–531.
[4] M.K. Mondal, H.K. Balsora, P. Varshney, Progress and trends in CO2 capture/separation technologies: A review, Energy. 46 (2012) 431–441.
[5] M. Amelio, P. Morrone, F. Gallucci, A. Basile, Integrated gasification gas combined cycle plant with membrane reactors: Technological and economical analysis, Energy Convers. Manag. 48 (2007) 2680–2693.
[6] P. Chiesa, T.G. Kreutz, G.G. Lozza, CO2 Sequestration From IGCC Power Plants by Means of Metallic Membranes, J. Eng. Gas Turbines Power. 129 (2007) 123.
[7] M. Mavroudi, S.P. Kaldis, G.P. Sakellaropoulos, Reduction of CO2 emissions by a membrane contacting process, in: Fuel, 2003: pp. 2153–2159.
[8] R. Maceiras, E. Alvarez, M.A. Cancela, Effect of temperature on carbon dioxide absorption in monoethanolamine solutions, Chem. Eng. J. 138 (2008) 295–300.
[9] K.B. Lee, M.G. Beaver, H.S. Caram, S. Sircar, Reversible Chemisorbents for Carbon Dioxide and Their Potential Applications, Ind. Eng. Chem. Res. 47 (2008) 8048–8062.
[10] S.C. Lee, H.J. Chae, S.J. Lee, B.Y. Choi, C.K. Yi, J.B. Lee, et al., Development of regenerable MgO-based sorbent promoted with K2CO3 for CO2 capture at low temperatures., Environ. Sci. Technol. 42 (2008) 2736–2741.
[11] G. Xiao, R. Singh, A. Chaffee, P. Webley, Advanced adsorbents based on MgO and K2CO3 for capture of CO2 at elevated temperatures, Int. J. Greenh. Gas Control. 5 (2011) 634–639.
[12] S. Choi, J.H. Drese, C.W. Jones, Adsorbent materials for carbon dioxide capture from large anthropogenic point sources., ChemSusChem. 2 (2009) 796–854.
[13] Q. Wang, J. Luo, Z. Zhong, A. Borgna, CO2 capture by solid adsorbents and their applications: current status and new trends, Energy Environ. Sci. 4 (2011) 42.
[14] S. Wang, S. Yan, X. Ma, J. Gong, Recent advances in capture of carbon dioxide using alkali-metal-based oxides, Energy Environ. Sci. 4 (2011) 3805.
[15] S.F. Wu, Q.H. Li, J.N. Kim, K.B. Yi, Properties of a Nano CaO/ Al2O3 CO2 Sorbent, (2008) 180–184.
[16] A. Roesch, E.P. Reddy, P.G. Smirniotis, Parametric Study of Cs / CaO Sorbents with Respect to Simulated Flue Gas at High Temperatures, (2010) 6485–6490.
[17] K.O. Albrecht, K.S. Wagenbach, J.A. Satrio, B.H. Shanks, T.D. Wheelock, Development of a CaO-Based CO2 Sorbent with Improved Cyclic Stability, (2008) 7841–7848.
[18] J.C. Abanades, E.J. Anthony, D.Y. Lu, C. Salvador, D. Alvarez, Capture of CO2 from combustion gases in a fluidized bed of CaO, AIChE J. 50 (2004) 1614–1622.
[19] H. Lu, E.P. Reddy, P.G. Smirniotis, Calcium oxide based sorbents for capture of carbon dioxide at high temperatures, Ind. Eng. Chem. Res. 45 (2006) 3944–3949.
[20] J. Przepiorski, A. Czyżewski, R. Pietrzak, B. Tryba, MgO/CaO-loaded porous carbons for carbon dioxide capture, J. Therm. Anal. Calorim. 111 (2012) 357–364.
[21] A. Hassanzadeh, J. Abbasian, Regenerable MgO-based sorbents for high-temperature CO2 removal from syngas: 1. Sorbent development, evaluation, and reaction modeling, Fuel. 89 (2010) 1287–1297.
[22] M.B. Jensen, L.G.M. Pettersson, O. Swang, U. Olsbye, CO2 sorption on MgO and CaO surfaces: a comparative quantum chemical cluster study., J. Phys. Chem. B. 109 (2005) 16774–16781.
[23] M. Bhagiyalakshmi, J.Y. Lee, H.T. Jang, Synthesis of mesoporous magnesium oxide: Its application to CO2 chemisorption, Int. J. Greenh. Gas Control. 4 (2010) 51–56.
[24] D.L. Meixner, D.A. Arthur, S.M. George, Kinetics of desorption , on MgO ( 100 ) adsorption ,, (1992).
[25] C.D. Daub, G.N. Patey, D.B. Jack, A.K. Sallabi, Monte Carlo simulations of the adsorption of CO2 on the MgO(100) surface., J. Chem. Phys. 124 (2006) 114706.
[26] K. Zhang, X.S. Li, Y. Duan, D.L. King, P. Singh, L. Li, International Journal of Greenhouse Gas Control Roles of double salt formation and NaNO3 in Na2CO3-promoted MgO absorbent for intermediate temperature CO2 removal, 12 (2013) 351–358.
[27] N.N. a H. Meis, J.H. Bitter, K.P. De Jong, On the Influence and Role of Alkali Metals on Supported and Unsupported Activated Hydrotalcites for CO2 Sorption, Ind. Eng. Chem. Res. 49 (2010) 8086–8093.
[28] E.P. Reddy, P.G. Smirniotis, High-Temperature Sorbents for CO2 Made of Alkali Metals Doped on CaO Supports, (2004) 7794–7800.
[29] J.M. Montero, K. Wilson, A.F. Lee, Cs Promoted Triglyceride Transesterification Over MgO Nanocatalysts, Top. Catal. 53 (2010) 737–745.
[30] J. Lu, M. Cheng, Y. Ji, H. Zhang, Membrane-based CO2 absorption into blended amine solutions, J. Fuel Chem. Technol. 37 (2009) 740–746.
[31] J.G.J. Olivier, G. Janssen-Maenhout, M. Muntean, J.A.H.W. Peters, Trends in global CO2 emissions 2013 report, 2013.
[32] UNEP, The Emissions Gap Report 2013, United Nation Environment Programme, Nairobi, 2013.
[33] IPCC, Summary for Policymakers, in: Clim. Chang. 2007 Phys. Sci. Basis. Contrib. Work. Gr. I to Fourth Assess. Rep. Intergov. Panel Clim. Chang., 2007: pp. 1–18.
[34] A. Car, C. Stropnik, W. Yave, K.V. Peinemann, Pebax??/polyethylene glycol blend thin film composite membranes for CO2 separation: Performance with mixed gases, Sep. Purif. Technol. 62 (2008) 110–117.
[35] D. Figueroa, T. Fout, S. Plasynski, H. Mcilvried, R.D. Srivastava, Advances in CO2 capture technology — The U . S . Department of Energy ’ s Carbon Sequestration Program §, Transportation (Amst). 2 (2008) 9–20.
[36] E. Blomen, C. Hendriks, F. Neele, Capture technologies: Improvements and promising developments, in: Energy Procedia, 2009: pp. 1505–1512.
[37] K. Damen, M. Van Troost, A. Faaij, W. Turkenburg, A comparison of electricity and hydrogen production systems with CO2 capture and storage. Part A: Review and selection of promising conversion and capture technologies, Prog. Energy Combust. Sci. 32 (2006) 215–246.
[38] J. Gibbins, H. Chalmers, Carbon capture and storage, Energy Policy. 36 (2008) 4317–4322.
[39] R. Steeneveldt, B. Berger, T.A. Torp, CO2 Capture and Storage: Closing the Knowing–Doing Gap, Chem. Eng. Res. Des. 84 (2006) 739–763.
[40] T. Burdyny, H. Struchtrup, Hybrid membrane/cryogenic separation of oxygen from air for use in the oxy-fuel process, Energy. 35 (2010) 1884–1897.
[41] S.X. M. AxeL, Research and development issues in CO2 capture, Energy Convers. Manag. 38 (1997) 37–42.
[42] M.J. Tuinier, M. van Sint Annaland, G.J. Kramer, J.A.M. Kuipers, Cryogenic CO2 capture using dynamically operated packed beds, Chem. Eng. Sci. 65 (2010) 114–119.
[43] B. Mckee, Solution for 21st century, zero emissions technologies for fossil fuels, IEA Work. Party Foss. Fuels. (2002) 1–47.
[44] A. Brunetti, F. Scura, G. Barbieri, E. Drioli, Membrane technologies for CO2 separation, J. Memb. Sci. 359 (2010) 115–125.
[45] Olajire A. Abass, CO2 capture and separation technologies for end-of-pipe applications: a review, Energy. 35 (2010) 2610–2628.
[46] W.J. Choi, J.B. Seo, S.Y. Jang, J.H. Jung, K.J. Oh, Removal characteristics of CO2 using aqueous MEA/AMP solutions in the absorption and regeneration process, J. Environ. Sci. 21 (2009) 907–913.
[47] A.B. Rao, E.S. Rubin, A technical, economic, and environmental assessment of amine-based CO2 capture technology for power plant greenhouse gas control., Environ. Sci. Technol. 36 (2002) 4467–4475.
[48] S. Ma’mun, V.Y. Dindore, H.F. Svendsen, Kinetics of the Reaction of Carbon Dioxide with Aqueous Solutions of 2-((2-Aminoethyl)amino)ethanol, Ind. Eng. Chem. Res. 46 (2007) 385–394.
[49] A.L. Kohl, R.B. Nielsen, Gas Purification, 1997.
[50] S.-W. Park, J.-W. Lee, B.-S. Choi, J.-W. Lee, Absorption of carbon dioxide into non-aqueous solutions of N-methyldiethanolamine, Korean J. Chem. Eng. 23 (2006) 806–811.
[51] P. Riemer, Greenhouse gas mitigation technologies, an overview of the CO2 capture, storage and future activities of the IEA Greenhouse Gas R&D programme, Energy Convers. Manag. 37 (1996) 665–670.
[52] S.W. and R. Bioletti, Carbon dioxide separation technologies, Canada, 2002.
[53] M. Hasib-ur-Rahman, M. Siaj, F. Larachi, Ionic liquids for CO2 capture-Development and progress, Chem. Eng. Process. Process Intensif. 49 (2010) 313–322.
[54] J. Blamey, E.J. Anthony, J. Wang, P.S. Fennell, The calcium looping cycle for large-scale CO2 capture, Prog. Energy Combust. Sci. 36 (2010) 260–279.
[55] H. Yang, Z. Xu, M. Fan, R. Gupta, R.B. Slimane, A.E. Bland, et al., Progress in carbon dioxide separation and capture: A review, J. Environ. Sci. 20 (2008) 14–27.
[56] N. Hedin, L. Chen, A. Laaksonen, Sorbents for CO2 capture from flue gas--aspects from materials and theoretical chemistry., Nanoscale. 2 (2010) 1819–1841.
[57] V. Manovic, E.J. Anthony, Lime-based sorbents for high-temperature CO2 capture--a review of sorbent modification methods., Int. J. Environ. Res. Public Health. 7 (2010) 3129–3140
[58] C. a. Scholes, K.H. Smith, S.E. Kentish, G.W. Stevens, CO2 capture from pre-combustion processes—Strategies for membrane gas separation, Int. J. Greenh. Gas Control. 4 (2010) 739–755.
[59] K.B. Lee, M.G. Beaver, H.S. Caram, S. Sircar, Chemisorption of Carbon Dioxide on Sodium Oxide Promoted Alumina, 53 (2007).
[60] O. Li, H.A. Mosqueda, C. Vazquez, P. Bosch, H. Pfeiffer, Chemical Sorption of Carbon Dioxide ( CO 2 ) on Lithium Oxide, (2006) 2307–2310.
[61] F. ZEMAN, Effect of steam hydration on performance of lime sorbent for CO2 capture, Int. J. Greenh. Gas Control. 2 (2008) 203–209.
[62] B. Feng, H. An, E. Tan, Screening of CO2 Adsorbing Materials for Zero Emission Power Generation Systems †, (2007) 426–434.
[63] H. Hattori, Solid base catalysts: generation of basic sites and application to organic synthesis, Appl. Catal. A Gen. 222 (2001) 247–259.
[64] P. Pal, S.K. Pahari, A. Sinhamahapatra, A.K. Giri, H.C. Bajaj, A.B. Panda, Porous cesium impregnated MgO (Cs–MgO) nanoflakes with excellent catalytic activity for highly selective rapid synthesis of flavanone, RSC Adv. 3 (2013) 2802.
[65] S. Coluccia, A.. Tench, No Title, in: Proceeding 7th Int. Congr. Catal., Tokyo, 1980: p. 1160.
[66] Z. Yong, V. Mata, A.E. Rodrigues, Adsorption of carbon dioxide on basic alumina at high temperatures, J. Chem. Eng. Data. 45 (2000) 1093–1095.
[67] T. Horiuchi, H. Hidaka, T. Fukui, Y. Kubo, M. Horio, K. Suzuki, et al., Effect of added basic metal oxides on CO2 adsorption on alumina at elevated temperatures, Appl. Catal. A Gen. 167 (1998) 195–202.
[68] S. Walspurger, L. Boels, P.D. Cobden, G.D. Elzinga, W.G. Haije, R.W. van den Brink, The crucial role of the K+-aluminium oxide interaction in K+-promoted alumina- and hydrotalcite-based materials for CO2 sorption at high temperatures., ChemSusChem. 1 (2008) 643–50.
[69] C. Zhao, X. Chen, E.J. Anthony, X. Jiang, L. Duan, Y. Wu, et al., Capturing CO2 in fl ue gas from fossil fuel- fi red power plants using dry regenerable alkali metal-based sorbent, 39 (2013).
[70] O.C.S. D.P. Hagewiesche, S.S. Ashour, H.A. Al-Ghawas, Absorption of carbon dioxide into aqueous blends of monoethanolamine and N-methyldiethanolamine, Chem. Eng. Sci. 50 (1995) 1071–1079.
[71] W.C.Y. J. Ciferno, S Chen, Analyses of hot/warm CO2 capture for IGCC processes, in: 2008 AIChE Spring Natl. Meet., New Orleans, 2008.
[72] G. S. Grasa and J. C. Abanades, CO2 capture capacity of CaO in long series of carbonation/calcination cycles, Ind. Eng. Chem. Res. 45 (2006) 8846–8851.
[73] J.C. Abanades, The maximum capture efficiency of CO2 using a carbonation/calcination cycle of CaO/CaCO3, Chem. Eng. J. 90 (2002) 303–306.
[74] X.P. Wang, J.J. Yu, J. Cheng, Z.P. Hao, Z.P. Xu, High-temperature adsorption of carbon dioxide on mixed oxides derived from hydrotalcite-like compounds., Environ. Sci. Technol. 42 (2008) 614–618.
[75] S.P. Reynolds, A.D. Ebner, J.A. Ritter, Stripping PSA Cycles for CO2 Recovery from Flue Gas at High Temperature Using a Hydrotalcite-Like Adsorbent, Ind. Eng. Chem. Res. 45 (2006) 4278–4294.
[76] E.L.G. Oliveira, C.A. Grande, A.E. Rodrigues, CO2 sorption on hydrotalcite and alkali-modified (K and Cs) hydrotalcites at high temperatures, Sep. Purif. Technol. 62 (2008) 137–147.
[77] N.D. Hutson, B.C. Attwood, High temperature adsorption of CO2 on various hydrotalcite-like compounds, Adsorption. 14 (2008) 781–789.
[78] F. Meshkani, M. Rezaei, Facile synthesis of nanocrystalline magnesium oxide with high surface area, Powder Technol. 196 (2009) 85–88.
[79] M. Husein, E. Rodil, J. Vera, Formation of Silver Chloride Nanoparticles in Microemulsions by Direct Precipitation with the Surfactant Counterion, Langmuir. 19 (2003) 8467–8474.
[80] Y. Dai, T. Deng, S. Jia, L. Jin, F. Lu, Preparation and characterization of fine silver powder with colloidal emulsion aphrons, J. Memb. Sci. 281 (2006) 685–691.
[81] N.H. Kim, J.-Y. Kim, K.J. Ihn, Preparation of silver nanoparticles having low melting temperature through a new synthetic process without solvent., J. Nanosci. Nanotechnol. 7 (2007) 3805–9.
[82] R.G. Lopez, P.Y. Reyes, J.A. Espinoza, M.E. Trevino, H. Saade, Synthesis of silver nanoparticles by precipitation in bicontinuous microemulsions, J. Nanomater. 2010 (2010).
[83] K.-S. Chou, Y.-C. Chang, L.-H. Chiu, Studies on the Continuous Precipitation of Silver Nanoparticles, Ind. Eng. Chem. Res. 51 (2012) 4905–4910.
[84] M. Zhu, P. Chen, W. Ma, B. Lei, M. Liu, Template-free synthesis of cube-like Ag/AgCl nanostructures via a direct-precipitation protocol: highly efficient sunlight-driven plasmonic photocatalysts., ACS Appl. Mater. Interfaces. 4 (2012) 6386–92.
[85] M.S. Mastuli, N.S. Ansari, M.A. Nawawi, A.M. Mahat, Effects of Cationic Surfactant in Sol-gel Synthesis of Nano Sized Magnesium Oxide, APCBEE Procedia. 3 (2012) 93–98.
[86] B.-Q. Xu, J.-M. Wei, H.-Y. Wang, K.-Q. Sun, Q.-M. Zhu, Nano-MgO: novel preparation and application as support of Ni catalyst for CO2 reforming of methane, Catal. Today. 68 (2001) 217–225.
[87] M.S. Mastuli, N.S. Ansari, M.A. Nawawi, A.M. Mahat, Effects of Cationic Surfactant in Sol-gel Synthesis of Nano Sized Magnesium Oxide, APCBEE Procedia. 3 (2012) 93–98.
[88] Y. Ding, G. Zhang, H. Wu, B. Hai, L. Wang, Nanoscale Magnesium Hydroxide and Magnesium Oxide Powders : Control over Size , Shape , and Structure via Hydrothermal Synthesis, (2001) 435–440.
[89] G. Messing, Ceramic powder synthesis by spray pyrolysis, … Am. Ceram. …. 76 (1993) 2707.
[90] M. Eslamian, N. Ashgriz, Effect of precursor, ambient pressure, and temperature on the morphology, crystallinity, and decomposition of powders prepared by spray pyrolysis and drying, Powder Technol. 167 (2006) 149–159.
[91] M. Rezaei, M. Khajenoori, B. Nematollahi, Preparation of nanocrystalline MgO by surfactant assisted precipitation method, Mater. Res. Bull. 46 (2011) 1632–1637.
[92] M. Rezaei, M. Khajenoori, B. Nematollahi, Preparation of nanocrystalline MgO by surfactant assisted precipitation method, Mater. Res. Bull. 46 (2011) 1632–1637.
[93] A. Kumar, J. Kumar, On the synthesis and optical absorption studies of nano-size magnesium oxide powder, J. Phys. Chem. Solids. 69 (2008) 2764–2772.
[94] B.-Q. Xu, J.-M. Wei, H.-Y. Wang, K.-Q. Sun, Q.-M. Zhu, Nano-MgO: novel preparation and application as support of Ni catalyst for CO2 reforming of methane, Catal. Today. 68 (2001) 217–225.
[95] B. Nagappa, G.T. Chandrappa, J. Livage, Synthesis, characterization and applications of nanostructural/nanodimensional metal oxides, Pramana. 65 (2005) 917–923.
[96] X. Li, W. Xiao, G. He, W. Zheng, N. Yu, M. Tan, Pore size and surface area control of MgO nanostructures using a surfactant-templated hydrothermal process: High adsorption capability to azo dyes, Colloids Surfaces A Physicochem. Eng. Asp. 408 (2012) 79–86.
[97] J.-M. Han, D.-S. Jung, S.-H. Lee, Y.-C. Kang, Nano-sized MgO particles ranging from 13 to 28 nm synthesized by spray pyrolysis, 9 (2008) 140–145.
[98] Y.-H. Choa, J.-K. Yang, W.-J. Yang, K.-H. Auh, Synthesis and characterization of isolated iron oxide nanoparticle dispersed in MgO matrix, J. Magn. Magn. Mater. 266 (2003) 20–27.
[99] W. Liu, H. Jiang, K. Tian, Y. Ding, H. Yu, Mesoporous Carbon Stabilized MgO Nanoparticles Synthesized by Pyrolysis of MgCl2 Preloaded Waste Biomass for Highly E ffi cient CO2 Capture, (2013).
[100] P.S. Patil, Versatility of chemical spray pyrolysis technique, Mater. Chem. Phys. 59 (1999) 185–198.
[101] S. Nešić, J. Vodnik, Kinetics of droplet evaporation, Chem. Eng. Sci. 46 (1991) 527–537.
[102] H.F.. H.F.J. Kraemer, Collection of aerosol particles in presence of electrostatic fields, Ind. Eng. Chem. Res. 47 (1955) 2426–2434.
[103] Magnesium acetate tetrahydrate, Chem. B. (2010).
[104] S.-J. Shih, I.-C. Chien, Preparation and characterization of nanostructured silver particles by one-step spray pyrolysis, Powder Technol. 237 (2013) 436–441.
[105] S.-J. Shih, Y.-Y. Wu, C.-Y. Chen, C.-Y. Yu, Controlled Morphological Structure of Ceria Nanoparticles Prepared by Spray Pyrolysis, Procedia Eng. 36 (2012) 186–194.