Talk:Metal–organic framework/Archive 1

Archive 1

"Electron-rich" needs clarification

Re "strong chemisorption that takes place between electron-rich, odor-generating molecules..."

There can be electron-rich regions on a molecule (see Electrophile), but if a molecule is itself electron-rich, that needs to be explained somehow. Maybe they're molecules with electron-rich sites? --Chriswaterguy talk 05:13, 17 August 2012 (UTC)

Temp/pressure of H2 storage

Under Other methods of hydrogen storage, I changed the following (bolding the changed word):

due to the extremely high pressure required for storing hydrogen gas or the extremely low pressure required for storing hydrogen liquid.

to

due to the extremely high pressure required for storing hydrogen gas or the extremely low temperature required for storing hydrogen liquid.

The source article is behind a paywall, but this way makes more sense - I don't see how 1 atmosphere is a difficult pressure to handle. I just mention it here in case I missed something important. --Chriswaterguy talk 04:58, 31 August 2012 (UTC)

Hydrogen storage

First we should clarify if this is reversible Hydrogen storage like MOFs or irreversible like the Borohydride and Aluminum Hydride 'method' some dissolving metal reactions. 1.) 800 bar for tank? Hydrogen tanks for our gas chromatograph is 6000 psi. 2.) Pd, Ni, FeTi, have significant internal 'absorption' (chemisorbtion since hydrogen is dissociated into atomic hydrogen) up to PdH2 (phase change at PdH1.7), NiH, and TiFeH2. The 'metal hydride' in Nickel Metal Hydride batteries is Raney Nickel type alloy. 3.) Surface absorption must obviously have a lower mass % since internal metal atoms outnumber external metal atoms by a significant margin, also chemisorbtion because Hydrogen is dissociated into atoms on the metal surface. Although colloidal Silver and colloidal Rhenium can react with Hydrogen, I'm not sure if we want ~2 as the mass %. 4.) Cyclohexane/cyclohexene are common sources of Hydrogen for organic reduction reactions with Palladium and Platinum and Nickel. Graphite can reversibly store and release Hydrogen. Methane and Carbon as reacted with Water is used as a source of Hydrogen for the Haber process (quoted in Wikipedia as using 8% of all Worlds energy). 5.) Dissolution of 7Li would yield 14 mass % of Hydrogen (Al and Si about the same). Rarer Be 20% and Boron 33% (not easy reaction). Boranes (were used as fuel for SR-71 aircraft) should be included with metal borohydrides. These of course would all be non-reversible Hydrogen storage. 6.) Calculations for volumetric storage of Hydrogen (total energy content; e.g. for Hydrogen powered vehicle) showed Raney Ni powder filled cylinder stored more Hydrogen fuel at modest pressures than 6000psi steel cylinder. Composite cylinders don't have the safety record at high pressures to suggest use in a (accident prone) mobile environment, and steel cylinders have a significant weight disadvantage. (Ni-H powder burns, not explodes like H2 or LNG.) 184.76.59.220 (talk) 20:13, 11 May 2013 (UTC)

Untitled

IUPAC has now with the help of its task group made recommendations about metal organic frameworks and coordination polymers. Consequently the introduction has been changed and the section on metal organic frameworks vs coordination polymers has been deleted.--LRO 12:05, 10 August 2013 (UTC) — Preceding unsigned comment added by Lrohrstrom (talk • contribs)

There is no consensus in the scientific community about the definition of "metal-organic framework" and I believe the article should be edited accordingly. There us currently an IUPAC Task Group on "Coordination Polymers and Metal Organic Frameworks: Terminology and Nomenclature Guidelines" see Chemistry International, vol. 32, No1, 2010, http://www.iupac.org/publications/ci/2010/3201/pp1_2009-012-2-200.html, and the project webpage http://www.iupac.org/web/ins/2009-012-2-200.

I am reluctant to immediately delete large portions of this text, instead i would like to suggest that the author(s) modify it to better reflect the present situation. LRO (talk) 19:47, 20 April 2010 (UTC)

We are working on a subsection that will be titled "MOFs for Catalysis" Andchemist (talk) 20:22, 5 October 2011 (UTC)

The statement " Hydrogen has the potential to be an attractive option because it has a high energy content (120 MJ/kg compared to 44 MJ/kg for gasoline), produces clean exhaust product (water vapor without CO2 or NOx), and can be derived from a variety of primary energy sources." is incorrect. While Hydrogen fueled Internal Combustion engines do not emmit C02, they still have the same NOx problems as other fuels, if anything it is worse. Just heating air creates NOx, and H2 burns hot. — Preceding unsigned comment added by 210.193.170.17 (talk) 03:54, 20 January 2012 (UTC)