Catalytic oxidation of methanol

In the chemical industry, simple aldehydes and ketones are produced in large quantities for use as solvents and as starting materials to prepare a host of other compounds. For example, more than 1.9 million tons per year of formaldehyde, H2C=0, is produced in the United States for use in building insulation materials and in the adhesive resins that bind particle hoard and plywood. Acetone, (CH.3)2C"0, is widely used as an industrial solvent approximately 1.2 million tons per year is produced in the United States. Formaldehyde is synthesized industrial ) by catalytic oxidation of methanol, and one method of acetone preparation involves oxidation of 2-propanol. 

Formaldehyde is prepared industrially (for the manufacture of phenol-formaldehyde resins) by the catalytic oxidation of methanol ... 

The industrial preparation of formaldehyde has occurred since the late 1800s and involves the catalytic oxidation of methanol 2CH,OH,. + 0 ,. —> 2CH 0,.. The oxidation takes place at temperatures between 400°C and 700°C in the presence of metal catalysts. Metals include silver, copper, molybdenum, platinum, and alloys of these metals. Formaldehyde is commonly used as an aqueous solution called formalin. Commercial formalin solutions vary between 37% and 50% formaldehyde. When formalin is prepared, it must be heated and a methanol must be added to prevent polymerization the final formalin solution contains between 5% and 15% alcohol. 

H4SiMo12O40 on the support for catalytic oxidation of methanol (184). At coverages larger than 0.25 monolayer, the selectivities remain constant dimethyl ether is the main product (about 80%), showing the acidic character of the catalyst. Below 0.25 monolayer, the acidic character is lowered, and dimethyl ether rapidly disappears. 

Bittger, I., Pettinger, B., Schedel-Niedrig, T. et al. (2001) Self Sustained Oscillations Over Copper in the Catalytic Oxidation of Methanol, Elsevier, Amsterdam. 

Commercial formaldehyde (formalin) 37% formaldehyde 10% methanol, 53% w/w water. 8750 longtons Vapour-phase autothermal catalytic oxidation of methanol. 

Figure 20 shows an example of the CTL spectra during catalytic oxidation of methanol, ethylene, and / so-butanc on y-Al203 activated with Dy [18]. Each component of the CTL spectrum from the catalyst activated with the rare-earth ion is attributed to the electronic transition within the activator. The intensity of each component, however, does not agree with that of the corresponding component in the photoluminescence spectrum. Details of the excitation process of the activator by carriers originating from the chemisorbed species have not been clarified yet. 

Fig. 20 Examples of CTL spectra during catalytic oxidation of methanol, ethylene, and isobutane on y-ALCbiDy...

Brandhorst M, Cristol S, Capron M, et al. Catalytic oxidation of methanol on M0/AI2O3 catalyst an EPR and Raman/infrared operando spectroscopies study. Catal Today. 2006 113 34. 

The catalytic oxidation of methanol produces formaldehyde and water (cqn. 1) ... 

Catalytic oxidation of methanol in the presence of a catalyst based on transition metal oxides produces good yields of formaldehyde [17]. Both... 

Abdel Rahim, M.A., Hassan, H.B., and Andel Hamid, R.M. 2006. A systematic study of the effect of OIF and NF+ ions on the electro-catalytic oxidation of methanol at Ni-S-1 electrode. Journal of Power Sources 154, 59-65. 

X. Bao, M. Muhler, B. Pettinger, R. Schlogl, and G. Ertl, On the Nature of the Active State of Silver During Catalytic Oxidation of Methanol, Catal. Lett. 22, 215 (1993)... 

S. Palmero, A. Colina, E. Munoz, A. Heras, V. Ruiz, and J. Lopez-Palacios, layer-by-layer electrosynthesis of Pt-polyaniline nanocomposites for the catalytic oxidation of methanol, Electrochem. Commun., 11, 122-125 (2009)... 

Preparation and characterization of PANI/NiO nanocomposite using various surfactants, e.g., polyvinyl alcohol and hydroxypropylcellulose, were reported by Aleahmad et al. [230]. PANl and NiO were electro-codeposited from aniline and NiSO through cyclic voltammetric scans at controlled acidity leading thus to the formation of PANI/NiO composite film [231]. The stability of NiO in the composite films against acidic environments was found to be enhanced in comparison with the corresponding stability of pure NiO. Electrochemical catalytic behavior of PANl/NiO composite film was demonstrated by the catalytic oxidation of methanol and ethanol. Multicolored electrochromic thin films of... 

The typical electrodeposition process observed with nickel derivatives was first investigated by Milczarek using a Ni(II) tetrakis(3-methoxy-4-hydroxyphenyl) porphyrin as a monomer. The resulting conductive film was used for the electro-catalytic oxidation of methanol and other simple alcohols , nitric oxide, formaldehyde , or ascorbic acid and NADH. Later, [Ni(II)-69], [Ni(II)-70] and [Ni(II)-71] were shown to provide a large benefit in the electrochemical determination of nitric oxide in aqueous solution or for the electrocatalytic... 

Jafarian M, Moghaddam RB, Mahjani MG, Gobal F (2006) Electro-catalytic oxidation of methanol on a Ni-Cu alloy in alkaline medium. J Appl Electrochem 36(8) 913-918... 

Ciszewski A (1995) Catalytic oxidation of methanol on a glassy carbon electrode electro-chemically modified by a conductive Ni-II-curcumin film. Electroanalysis 7(12) 1132-1135... 

The mechanism of the catalytic oxidation of methanol to formaldehyde seems to be dependent on the reaction conditions, namely on temperature. 

H. Zhang, Y. Wang, E.R. Fachini, C.R. Cabrera, 1999. Electrochemically codeposited PtMo oxide electrode for catalytic oxidation of methanol in acid solution. Electrochemical and Solid State Letters, 2 437—439. 

Arakawa, T Ohara, N., Karachi, H., and Shiokawa, J. (1985) Catalytic oxidation of methanol on LnCo03 (Ln = La, Eu) perovskite oxides. J. Colloid Interface ScL,... 

Cao, E., Firth, S., McMillan, P, et al. (2007). Application of Microfabricated Reactors for Operando Raman Studies of Catalytic Oxidation of Methanol to Formaldehyde on Silver, Catal. Today, 126, pp. 119-126. 

Catalytic Oxidation - The catalytic oxidation of methanol using platinum wire is of interest as it is used in model aircraft engines to replace the sparking plug arrangement of the conventional petrol engine. The heat of reaction is sufficient to spark the engine. 

Lichtenberger J, Lee D, Iglesia E (2007) Catalytic oxidation of methanol on Pd metal and oxide clusters at near-ambient temperatures. Phys Chem Chem Phys 9 4902-4906... 

---