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    Assuming cellulose with the chemical formula C6H10O5.......what happens if:

    1) the cellulose is subjected to concentrated H2SO4 (sulfuruc acid) ---- how is the cellulose molecule/structure modified? and what are the reaction by-products.

    2) similarly, what happens if cellulose is reacted with maleic anhydride C4H2O3? Again, how is the cellulose molecule/structure altered and what are the reaction by-products?

    © BrainMass Inc. brainmass.com December 24, 2021, 9:40 pm ad1c9bdddf
    https://brainmass.com/chemistry/organic-chemistry-bonding/cellulose-chemistry-403204

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    I hope this helps. The references should provide further reading.

    Brainmass Posting 403204
    Cellulose macromolecules are composed of D-glucose units linked together by β-1,4 glycosidic linkages in linear, unbranched chains. Reaction of purified cellulose with concentrated sulfuric acid can lead to hydrolysis and (under certain conditions) sulfation -
    Hydrolysis

    *http://www.turon.com/papers/ethanol.htm
    The reaction itself is heterogeneous and influenced by physical factors including the nature of the cellulose stock in addition to the reaction conditions i.e. temperature, acid conc.). The mechanism of acid-catalyzed hydrolysis of cellulose involves cleavage of the β-1-4-glycosidic bond. Initial addition of a proton to the glycosidic oxygen linking two sugar units forms the conjugate acid. Following rapid addition of water, free sugar and a proton are liberated. This process is of major importance in alcohol production

    In acid catalyzed cellulose hydrolysis, in addition to glucose, several other bi-products are formed including hydroxymethylfurfural (3), levulinic acid (4) and formic acid (5). The figure below is taken from reference (Girisuta, B.; Janssen, L. P. B. M.; Heeres, H. J., Kinetic study on the acid-catalyzed hydrolysis of cellulose to levulinic acid. Ind. Eng. Chem. Res. 2007, 46, 1696-1708.)

    Sulfuric acid can react under certain conditions with cellulose to form cellulose sulfate. However using sulfuric acid the degree of substitution is low and there are much more efficient sulfation conditions for generating cellulose sulfate.

    "The rate of sulfation for the following sulfating agents is as follows: H2SO4<SO3<SO2Cl2<HSO3Cl, with SO2Cl2 generating the most chain degradation during sulfation... Chlorosulfonic acid is generally considered the most effective sulfation agent with regard to both sulfation and retention of chain length. ( http://www.scribd.com/doc/30137720/Cellulose-Esters-Inorganic-Esters)

    2) Similarly, what happens if cellulose is reacted with maleic anhydride C4H2O3? Again, how is the cellulose molecule/structure altered and what are the reaction by-products?

    Acid anhydrides are a source of reactive acyl groups. In this respect, the reactions resemble those of acyl halides. These anhydrides are quite active and will esterify alcohols (including cellulose). The reaction of cellulose with maleic anhydride is shown below. Maleic acid can also be formed as a by product.

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    © BrainMass Inc. brainmass.com December 24, 2021, 9:40 pm ad1c9bdddf>
    https://brainmass.com/chemistry/organic-chemistry-bonding/cellulose-chemistry-403204

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