Sample records for dimethoxymethane
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Energy Technology Data Exchange (ETDEWEB)
Sun, Q
2007-07-15
This work is related to the subject 'Clean Energy'. Dimethoxymethane (DMM) is a suitable H{sub 2} storage material for mobile application due to its high H{sub 2} content and non-toxicity. It was found that DMM can be 100% reformed to produce H{sub 2} on a complex catalyst composed of an acid component such as Nb{sub 2}O{sub 5} or niobium phosphate (NbP) combined with CuZnO/Al{sub 2}O{sub 3} catalyst. Moreover, V{sub 2}O{sub 5}/NbP and V{sub 2}O{sub 5}-TiO{sub 2}-SO{sub 4}{sup 2-} catalysts were prepared and evaluated in the reaction of selective oxidation of methanol to DMM. The surface acidic and redox properties of V{sub 2}O{sub 5}-TiO{sub 2}-SO{sub 4}{sup 2-} were correlated to the reactive performance of the catalysts. The adsorption properties of Nb{sub 2}O{sub 5} and NbP used in methanol dehydration reaction were also studied. (author)
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Reforming and synthesis of dimethoxymethane and dimethyl ether for H2 production
International Nuclear Information System (INIS)
Sun, Q.
2007-07-01
This work is related to the subject 'Clean Energy'. Dimethoxymethane (DMM) is a suitable H 2 storage material for mobile application due to its high H 2 content and non-toxicity. It was found that DMM can be 100% reformed to produce H 2 on a complex catalyst composed of an acid component such as Nb 2 O 5 or niobium phosphate (NbP) combined with CuZnO/Al 2 O 3 catalyst. Moreover, V 2 O 5 /NbP and V 2 O 5 -TiO 2 -SO 4 2- catalysts were prepared and evaluated in the reaction of selective oxidation of methanol to DMM. The surface acidic and redox properties of V 2 O 5 -TiO 2 -SO 4 2- were correlated to the reactive performance of the catalysts. The adsorption properties of Nb 2 O 5 and NbP used in methanol dehydration reaction were also studied. (author)
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Thermal decomposition of dimethoxymethane and dimethyl carbonate catalyzed by solid acids and bases
International Nuclear Information System (INIS)
Fu Yuchuan; Zhu Haiyan; Shen Jianyi
2005-01-01
The thermal decomposition of dimethoxymethane (DMM) and dimethyl carbonate (DMC) on MgO, H-ZSM-5, SiO 2 , γ-Al 2 O 3 and ZnO was studied using a fixed bed isothermal reactor equipped with an online gas chromatograph. It was found that DMM was stable on MgO at temperatures up to 623 K, while it was decomposed over the acidic H-ZSM-5 with 99% conversion at 423 K. On the other hand, DMC was easily decomposed on the strong solid base and acid. The conversion of DMC was 76% on MgO at 473 K, and 98% on H-ZSM-5 at 423 K. It was even easier decomposed on the amphoteric γ-Al 2 O 3 . Both DMM and DMC were relatively stable on SiO 2 possessing little surface acidity and basicity. They were even more stable on ZnO with the conversion of DMM and DMC of about 1.5% at 573 K. Thus, metal oxides with either strong acidity or basicity are not suitable for the selective oxidation of DMM to DMC, while ZnO may be used as a component for the reaction
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Liu, Jingwei; Sun, Qing; Fu, Yuchuan; Shen, Jianyi
2009-07-15
Mesoporous VO(x)-TiO(2) with high surface areas were prepared using the procedure of evaporation-induced self-assembly combined with ammonia posttreatment. The samples were characterized by X-ray diffraction (XRD), laser Raman spectroscopy (LRS), transmission electron microscopy (TEM), N(2) adsorption, temperature-programmed reduction (H(2)-TPR), microcalorimetry for the adsorption of NH(3), and isopropanol probe reaction. Their catalytic activities were evaluated for the reaction of selective oxidation of methanol to dimethoxymethane (DMM). It was found that the VO(x)-TiO(2) materials exhibited high surface areas with pore diameters of 4 nm. The vanadia species were highly dispersed in the VO(x)-TiO(2) within 30 wt% VO(x) content, evidenced by the results of XRD and LRS. The VO(x)-TiO(2) samples exhibited both surface acidic and redox properties. The surface acidity was further enhanced on the addition of SO(4)2-. The catalyst SO(4)2-/30VO(x)-TiO(2) exhibited good performance for the selective oxidation of methanol (57% conversion) to DMM (83% selectivity) at 423 K.
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One-pot conversion of biomass-derived xylose and furfural into levulinate esters via acid catalysis.
Hu, Xun; Jiang, Shengjuan; Wu, Liping; Wang, Shuai; Li, Chun-Zhu
2017-03-07
Direct conversion of biomass-derived xylose and furfural into levulinic acid, a platform molecule, via acid-catalysis has been accomplished for the first time in dimethoxymethane/methanol. Dimethoxymethane acted as an electrophile to transform furfural into 5-hydroxymethylfurfural (HMF). Methanol suppressed both the polymerisation of the sugars/furans and the Aldol condensation of levulinic acid/ester.
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Celik, Fuat Emin
2010-01-01
Carbon-carbon bond forming carbonylation reactions were investigated as candidates to replace ethene epoxidation as the major source of ethylene glycol production. This work was motivated by the potentially lower cost of carbon derived from synthesis gas as compared to ethylene. Synthesis gas can be produced from relatively abundant and cheap natural gas, coal, and biomass resources whereas ethylene is derived from increasingly scarce and expensive crude oil. From synthesis gas, a range of...
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Tröger’s Base Ladder Polymer for Membrane-Based Hydrocarbon Separation
Alhazmi, Abdulrahman
2017-05-01
The use of polymeric membranes for natural gas separation has rapidly increased during the past three decades, particularly for carbon dioxide separation from natural gas. Another valuable application is the separation of heavy hydrocarbons from methane (fuel gas conditioning), more importantly for remote area and off-shore applications. A new potential polymeric membrane that might be utilized for natural gas separations is a Tröger’s base ladder polymer (PIM-Trip-TB-2). This glassy polymeric membrane was synthesized by the polymerization reaction of 9, 10-dimethyl-2,6 (7) diaminotriptycene with dimethoxymethane. In this research, the polymer was selected due to its high surface area and highly interconnected microporous structure. Sorption isotherms of nitrogen (N2), oxygen (O¬2), methane (CH4), carbon dioxide (CO2), ethane (C2H6), propane (C3H8), and n-butane (n-C4H10) were measured at 35 °C over a range of pressures using a Hiden Intelligent Gravimetric Analyzer, IGA. The more condensable gases (C2H6, CO2, C3H8, and n-C4H10) showed high solubility due to their high affinity to the polymer matrix. The permeation coefficients were determined for various gases at 35 °C and pressure difference of 5 bar via the constant-pressure/variable-volume method. The PIM-Trip-TB-2 film exhibited high performance for several high-impact applications, such as O2/N2, H2/N2 and H2/CH4. Also, physical aging for several gases was examined by measuring the permeability coefficients at different periods of time. Moreover, a series of mixed-gas permeation tests was performed using 2 vol.% n-C4H10/98 vol.% CH4 and the results showed similar transport characteristics to other microporous polymers with pores of less than 2 nm. The work performed in this research suggested that PIM-Trip-TB-2 is suitable for the separation of: (i) higher hydrocarbons from methane and (ii) small, non-condensable gases such as O2/N2 and H2/CH4.
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International Nuclear Information System (INIS)
Sarkadi-Priboczki, E.; Kovacs, Z.
2004-01-01
over acid H-formed ZSM-5, Beta and MCM-41. The methanol transformation to dimethoxymethane and dimethyl ether was resulted by dehydrogenation and dehydration simultaneously over Cs-formed ZSM-5, Beta and MCM-41 catalysts. The methanol conversion over Cu-formed ZSM-5, Beta and MCM-41 catalysts gives a new information for clearing of the roles of H, Cs as alkali metal and Cu as transition metal in ZSM-5, Beta and MCM-41 supports. The acid-basic properties of the supports and the oxidation state and dispersion of copper was investigated effectively by methanol conversion using 11 C-radioactive labeling. This work was financially supported by the Hungarian Scientific Research Fund No. T031764. (author)