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  2. Steam cracking - Wikipedia

    en.wikipedia.org/wiki/Steam_cracking

    The propane dehydrogenation process may be accomplished through different commercial technologies. The main differences between each of them concerns the catalyst employed, design of the reactor and strategies to achieve higher conversion rates. [1] Olefins are useful precursors to myriad products. Steam cracking is the core technology that ...

  3. Cracking (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Cracking_(chemistry)

    In steam cracking, a gaseous or liquid hydrocarbon feed like naphtha, LPG or ethane is diluted with steam and briefly heated in a furnace without the presence of oxygen. Typically, the reaction temperature is very high, at around 850 °C, but the reaction is only allowed to take place very briefly.

  4. Wacker process - Wikipedia

    en.wikipedia.org/wiki/Wacker_process

    Oxygen from air is used up completely and the exhaust air is circulated as inert gas. Acetaldehyde – water vapor mixture is preconcentrated to 60–90% acetaldehyde by utilizing the heat of reaction and the discharged water is returned to the flash tower to maintain catalyst concentration. A two-stage distillation of the crude acetaldehyde ...

  5. Ethylene - Wikipedia

    en.wikipedia.org/wiki/Ethylene

    Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula C 2 H 4 or H 2 C=CH 2. It is a colourless, flammable gas with a faint "sweet and musky " odour when pure. [ 7 ] It is the simplest alkene (a hydrocarbon with carbon–carbon double bonds ).

  6. Photosynthetic efficiency - Wikipedia

    en.wikipedia.org/wiki/Photosynthetic_efficiency

    The Gibbs free energy for converting a mole of CO 2 to glucose is 114 kcal, whereas eight moles of photons of wavelength 600 nm contains 381 kcal, giving a nominal efficiency of 30%. [2] However, photosynthesis can occur with light up to wavelength 720 nm so long as there is also light at wavelengths below 680 nm to keep Photosystem II ...

  7. Oxidative coupling of methane - Wikipedia

    en.wikipedia.org/wiki/Oxidative_coupling_of_methane

    The ethane subsequently undergoes dehydrogenation to form ethylene (C 2 H 4). The yield of the desired C 2 products is reduced by non-selective reactions of methyl radicals with the surface and oxygen in the gas phase, which produce (undesirable) carbon monoxide and carbon dioxide.

  8. Oxygen evolution - Wikipedia

    en.wikipedia.org/wiki/Oxygen_evolution

    Photosynthetic oxygen evolution is the fundamental process by which oxygen is generated in the earth's biosphere. The reaction is part of the light-dependent reactions of photosynthesis in cyanobacteria and the chloroplasts of green algae and plants. It utilizes the energy of light to split a water molecule into its protons and electrons for ...

  9. Sabatier reaction - Wikipedia

    en.wikipedia.org/wiki/Sabatier_reaction

    Paul Sabatier (1854-1941) winner of the Nobel Prize in Chemistry in 1912 and discoverer of the reaction in 1897. The Sabatier reaction or Sabatier process produces methane and water from a reaction of hydrogen with carbon dioxide at elevated temperatures (optimally 300–400 °C) and pressures (perhaps 3 MPa [1]) in the presence of a nickel catalyst.