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A '''methanol refomer''' is a device used in [[chemical engineering]], especially in the area of [[fuel cell]] technology, which can produce pure [[hydrogen]] gas and [[carbon dioxide]] by reacting a [[methanol]] and [[water]] (steam) mixture.
This is a preview for the new '''MathML rendering mode''' (with SVG fallback), which is availble in production for registered users.


:<math>\mathrm{ CH_3OH_{(g)} + H_2O_{(g)} \;\longrightarrow\; CO_2 + 3\ H_2 \qquad}  \Delta H_{R\ 298}^0 = 49.2\ \mathrm{kJ/mol} </math>
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<small>Methanol is transformed into hydrogen and carbon dioxide by pressure and heat and interaction with a [[catalysis|catalyst]].</small>
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== Technology ==
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A mixture of water and methanol with a molar [[concentration]] ratio (water:methanol) of 1.0&nbsp;-&nbsp;1.5 is pressurized to approximately 20 [[bar (unit)|bar]], vaporized and heated to a temperature of 250&nbsp;-&nbsp;360&nbsp;[[Celsius|°C]]. The hydrogen that is created is separated through the use of [[Pressure swing adsorption]] or a [[hydrogen-permeable membrane]] made of [[polymer]] or a [[palladium]] alloy.


There are two basic methods of conducting this process.
'''MathML'''
* The water-methanol mixture is introduced into a tube-shaped reactor where it makes contact with the catalyst. Hydrogen is then separated from the other [[reagent|reactants]] and products in a later chamber, either by pressure swing adsorption (PSA), or through use of a membrane where the majority of the hydrogen passes through. This method is typically used for larger, non-mobile units.
:<math forcemathmode="mathml">E=mc^2</math>
* The other process features an integrated reaction chamber and separation membrane, a [[membrane reactor]]. In this, relatively new approach, the reaction chamber is made to contain high-temperature, hydrogen-permeable membranes that can be formed of [[refractory metals]], palladium alloys, or a PdAg-coated [[ceramic]]. The hydrogen is thereby separated out of the reaction chamber as the reaction proceeds, This purifies the hydrogen and, as the reaction continues, increases both the reaction rate and the amount of hyrogen extracted.


With either design, not all of the hydrogen is removed from the product gases (raffinate). Since the remaining gas mixture still contains a significant amount of chemical energy, it is often mixed with air and burned to provide heat for the endothermic reforming reaction.
<!--'''PNG'''  (currently default in production)
:<math forcemathmode="png">E=mc^2</math>


== Advantages and disadvantages ==
'''source'''
Methanol reformers are being considered as a component of a hydrogen fuel cell-powered vehicle. A prototype car, the [[Mercedes-Benz NECAR|NECAR 5]], was introduced by [[Daimler-Chrysler]] in the year 2000. The primary advantage of a vehicle with a reformer is that it does not need a pressurized gas tank to store hydrogen fuel; instead methanol is stored as a liquid. The logistic implications of this are great; pressurized hydrogen is difficult to store and produce. Also, this could help ease the public's concern over the danger of hydrogen and thereby make fuel cell powered vehicles more attractive. However, methanol, like [[gasoline]], is toxic and (of course) flammable. The cost of the PdAg membrane and its susceptibility to damage by temperature changes provide obstacles to adoption.
:<math forcemathmode="source">E=mc^2</math> -->


Another problem is that although hydrogen power produces energy without CO<sub>2</sub>, a methanol reformer creates the gas as a byproduct. The high level of greenhouse gases in our atmosphere significantly contributes to [[global warming]].
<span style="color: red">Follow this [https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsection-rendering link] to change your Math rendering settings.</span> You can also add a [https://en.wikipedia.org/wiki/Special:Preferences#mw-prefsection-rendering-skin Custom CSS] to force the MathML/SVG rendering or select different font families. See [https://www.mediawiki.org/wiki/Extension:Math#CSS_for_the_MathML_with_SVG_fallback_mode these examples].


Methanol (prepared from natural gas) that is used in an efficient fuel cell, however, releases less CO<sub>2</sub> in the atmosphere than gasoline, in a net analysis.<ref>George A. Olah (2005). "Beyond Oil and Gas: The Methanol Economy". Angewandte Chemie International Edition 44 (18): 2636–2639. {{doi|10.1002/anie.200462121}}</ref>
==Demos==


== References ==
Here are some [https://commons.wikimedia.org/w/index.php?title=Special:ListFiles/Frederic.wang demos]:


<references/>
* Emonts, B. et al.: ''Compact methanol reformer test for fuel-cell powered light-duty vehicles'', J. Power Sources 71 (1998) 288-293
* Wiese, W. et al.: ''Methanol steam reforming in a fuel cell drive system'', J. Power Sources 84 (1999) 187-193
* Peters, R. et al.: ''Investigation of a methanol concept considering the particular impact of dynamics and long-term stability for use in a fuel-cell-powered passenger car'', J. Power Sources 86 (1999) 507-514


== See also ==
* accessibility:
*[[Steam reforming]]
** Safari + VoiceOver: [https://commons.wikimedia.org/wiki/File:VoiceOver-Mac-Safari.ogv video only], [[File:Voiceover-mathml-example-1.wav|thumb|Voiceover-mathml-example-1]], [[File:Voiceover-mathml-example-2.wav|thumb|Voiceover-mathml-example-2]], [[File:Voiceover-mathml-example-3.wav|thumb|Voiceover-mathml-example-3]], [[File:Voiceover-mathml-example-4.wav|thumb|Voiceover-mathml-example-4]], [[File:Voiceover-mathml-example-5.wav|thumb|Voiceover-mathml-example-5]], [[File:Voiceover-mathml-example-6.wav|thumb|Voiceover-mathml-example-6]], [[File:Voiceover-mathml-example-7.wav|thumb|Voiceover-mathml-example-7]]
*[[Partial oxidation]]
** [https://commons.wikimedia.org/wiki/File:MathPlayer-Audio-Windows7-InternetExplorer.ogg Internet Explorer + MathPlayer (audio)]
*[[PROX]]
** [https://commons.wikimedia.org/wiki/File:MathPlayer-SynchronizedHighlighting-WIndows7-InternetExplorer.png Internet Explorer + MathPlayer (synchronized highlighting)]
** [https://commons.wikimedia.org/wiki/File:MathPlayer-Braille-Windows7-InternetExplorer.png Internet Explorer + MathPlayer (braille)]
** NVDA+MathPlayer: [[File:Nvda-mathml-example-1.wav|thumb|Nvda-mathml-example-1]], [[File:Nvda-mathml-example-2.wav|thumb|Nvda-mathml-example-2]], [[File:Nvda-mathml-example-3.wav|thumb|Nvda-mathml-example-3]], [[File:Nvda-mathml-example-4.wav|thumb|Nvda-mathml-example-4]], [[File:Nvda-mathml-example-5.wav|thumb|Nvda-mathml-example-5]], [[File:Nvda-mathml-example-6.wav|thumb|Nvda-mathml-example-6]], [[File:Nvda-mathml-example-7.wav|thumb|Nvda-mathml-example-7]].
** Orca: There is ongoing work, but no support at all at the moment [[File:Orca-mathml-example-1.wav|thumb|Orca-mathml-example-1]], [[File:Orca-mathml-example-2.wav|thumb|Orca-mathml-example-2]], [[File:Orca-mathml-example-3.wav|thumb|Orca-mathml-example-3]], [[File:Orca-mathml-example-4.wav|thumb|Orca-mathml-example-4]], [[File:Orca-mathml-example-5.wav|thumb|Orca-mathml-example-5]], [[File:Orca-mathml-example-6.wav|thumb|Orca-mathml-example-6]], [[File:Orca-mathml-example-7.wav|thumb|Orca-mathml-example-7]].
** From our testing, ChromeVox and JAWS are not able to read the formulas generated by the MathML mode.


[[Category:Hydrogen production]]
==Test pages ==
[[Category:Fuel cells]]
[[Category:Chemical engineering]]
[[Category:Membrane technology]]


[[de:Methanol-Reformer]]
To test the '''MathML''', '''PNG''', and '''source''' rendering modes, please go to one of the following test pages:
[[it:Reformer a metanolo]]
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*[[Styling]]
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*[[Help:Formula]]
 
*[[Inputtypes|Inputtypes (private Wikis only)]]
*[[Url2Image|Url2Image (private Wikis only)]]
==Bug reporting==
If you find any bugs, please report them at [https://bugzilla.wikimedia.org/enter_bug.cgi?product=MediaWiki%20extensions&component=Math&version=master&short_desc=Math-preview%20rendering%20problem Bugzilla], or write an email to math_bugs (at) ckurs (dot) de .

Latest revision as of 23:52, 15 September 2019

This is a preview for the new MathML rendering mode (with SVG fallback), which is availble in production for registered users.

If you would like use the MathML rendering mode, you need a wikipedia user account that can be registered here [[1]]

  • Only registered users will be able to execute this rendering mode.
  • Note: you need not enter a email address (nor any other private information). Please do not use a password that you use elsewhere.

Registered users will be able to choose between the following three rendering modes:

MathML


Follow this link to change your Math rendering settings. You can also add a Custom CSS to force the MathML/SVG rendering or select different font families. See these examples.

Demos

Here are some demos:


Test pages

To test the MathML, PNG, and source rendering modes, please go to one of the following test pages:

Bug reporting

If you find any bugs, please report them at Bugzilla, or write an email to math_bugs (at) ckurs (dot) de .

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