Problem of carbon dioxide

Problem of carbon dioxide

Nl8 probably distributed throughout the galaxy in circumstellar and interstellar dust clouds (H.W. Kroto & M. Jura, Astron. Astrophys., 293 (1992) 27...

76KB Sizes 7 Downloads 59 Views

Nl8

probably distributed throughout the galaxy in circumstellar and interstellar dust clouds (H.W. Kroto & M. Jura, Astron. Astrophys., 293 (1992) 275). So presumably they have been with us for some little time. Where is it all going? Predictions abound but the title of one recent paper (W. Marston, The Sciences, 32 (1992) 59) stands out from the rest, boldly positive in form but totally enigmatic in content: “Next -the Nanogizer Rabbit” CLIVE MCKEE Problem of Carbon Dioxide The carbon dioxide formed as a byproduct of energy creation in power plants and vented to the atmosphere is recognised as an environmental problem. This has to do with the fact that carbon dioxide is a greenhouse gas. The better known catalytic processes for the conversion of carbon dioxide are hydrogenation of carbon dioxide or carbon dioxide reforming of methane. These convert carbon dioxide to syngas (carbon monoxide and hydrogen). Syngas is, to a great extent, used for the production of fuels (Shell Middle Distillate Process, or Mobil’s Methanol to Gasoline, FischerTropsch Process, etc.). The fuel thus generated in time ends up as carbon dioxide in the atmosphere after use. The conversion of carbon dioxide to syngas cannot be considered as a solution to the problem of carbon dioxide in the atmosphere unless the syngas generated from carbon dioxide can be used to make solid materials, e.g., polymers such as polycarbonates, etc. Another possibility is to con-

applied catalysis A: General

vert carbon dioxide directly into solid polymers. A recent article (T.Tsude, K Maruta, and Y. Kiiaika in J. Am. Chem. Sot., 114 (1992) 1498) on copolymerization of carbon dioxide with unsaturated hydrocarbons is thereforevery interesting. They used NiO catalysts in the presence of some tertiary phosphines to copolymerize carbon dioxide and a di-yne such as 3,ll tetradoca-diyne (14 carbon atom straight chain hydrocarbon with triple bonds at 3rd and 1lth carbon atoms) to yield a brown solid polymer. Use of other di-ynes might be a way to vary the properties of the resulting polymers for various different applications. This development is certainly one of the directions that could bethought offorcarbon dioxide abatement. K. SESHAN Conference on Gas Sensors Information has been received on the 1st Vilnius Conference on Gas Sensors, to be held from 1 to 4 September 1993 in Vilnius, the capital of Lithuania. The main purpose of the conference is to discuss the latest achievements in establishing new physical concepts of gas sensing and to review the applications of such sensors. Topics of the conference include: physics, materials, technology and applications of optical, electrochemical and semiconducting devises for gas sensing. An attractive social programme will include a visit to the oldest East-European university and a conference dinner. More information can be obtained from V. Ambrazeviciene at the address given in the Calendar of Forthcoming Events.

Volume 98 No. 2 -

20 May 1993