When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  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. Conversion (chemistry) - Wikipedia

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

    Conversion and its related terms yield and selectivity are important terms in chemical reaction engineering.They are described as ratios of how much of a reactant has reacted (X — conversion, normally between zero and one), how much of a desired product was formed (Y — yield, normally also between zero and one) and how much desired product was formed in ratio to the undesired product(s) (S ...

  4. Ethanol fermentation - Wikipedia

    en.wikipedia.org/wiki/Ethanol_fermentation

    (3) The two molecules of NADH reduce the two acetaldehyde molecules to two molecules of ethanol; this converts NADH back into NAD+. Ethanol fermentation , also called alcoholic fermentation , is a biological process which converts sugars such as glucose , fructose , and sucrose into cellular energy , producing ethanol and carbon dioxide as by ...

  5. Cracking (chemistry) - Wikipedia

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

    In petrochemistry, petroleum geology and organic chemistry, cracking is the process whereby complex organic molecules such as kerogens or long-chain hydrocarbons are broken down into simpler molecules such as light hydrocarbons, by the breaking of carbon–carbon bonds in the precursors.

  6. Headspace gas chromatography for dissolved gas measurement

    en.wikipedia.org/wiki/Headspace_Gas...

    One of the most widely used methods for headspace analysis is described by the United States Environmental Protection Agency (USEPA). Originally developed by the R.S. Kerr USEPA Laboratory in Ada, Oklahoma as a "high quality, defendable, and documented way to measure" methane, ethane, and ethene, [7] [8] RSKSOP-175 is a standard operating procedure (SOP) and an unofficial method employed by ...

  7. 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 ).

  8. Azeotrope - Wikipedia

    en.wikipedia.org/wiki/Azeotrope

    A well-known example of a positive azeotrope is an ethanol–water mixture (obtained by fermentation of sugars) consisting of 95.63% ethanol and 4.37% water (by mass), which boils at 78.2 °C. [10] Ethanol boils at 78.4 °C, water boils at 100 °C, but the azeotrope boils at 78.2 °C, which is lower than either of its constituents. [11]

  9. Standard enthalpy of formation - Wikipedia

    en.wikipedia.org/wiki/Standard_enthalpy_of_formation

    For many substances, the formation reaction may be considered as the sum of a number of simpler reactions, either real or fictitious. The enthalpy of reaction can then be analyzed by applying Hess' law, which states that the sum of the enthalpy changes for a number of individual reaction steps equals the enthalpy change of the overall reaction.