7th principle of green chemistry 
     Use of renewable feedstocks: A raw material or feedstock should be renewable rather than depleting whenever 
     technically and economically practicable. 
     A feedstock is considered green if it satisfies the following conditions: 
     • It should impose least demands on the earth's resources. 
     • It‘s acquisition and refining should be safe. 
     • It should be non-hazardous and relatively safe. 
     • If possible, feedstock should always be renewable for example feedstocks from biomass that can be grown 
     repeatedly should be given preference to depletable petroleum feedstocks. 
     • Reusing of waste from bio-industries, if possible, as raw material or feedstock. Various examples are listed 
     below:
     1. Chitan, a waste from of seafood industry can be transformed into Chitosan by Deacetylation that has many 
      applications as in water purification, biomedical and in other industries. It would definitely replace the 
      petroleum feedstocks.
     2. Lignin, a waste from paper and pulp industry, is used as feedstock for manufacture of Annelyn venelin DMSO
    Continued….
    3. Lipids and hydrocarbon terpenes are the oils, greases and waxes which have   same 
    properties as that of petroleum products and are used to synthesize the synthetic liquid fuels 
    and also can be used directly as diesel fuel.
    4.  For chemical synthesis, the fatty acids from natural sources is advantageous because of 
    the carboxylic acid group and the presence of reactive  double bond between two carbon 
    atoms in the carbon chain. For example oleic acid from sunflower, linolenic acid from soya 
    bean and linseed, rinoleic acid from Castor oil etc.  
    5.  The carbohydrates as feedstocks have advantages as they have many hydroxyl functional 
    groups that may provide sites for the attachment of other functionalities or to initiate 
    chemical reactions.
    6.  Cellulose another bio feedstock is mostly employed as plant biomass suppliants thus 
    diminishing the need of petroleum feed stocks. 
    Biological processes 
    Biological processes produce a variety of biopolymers like cellulose. hemicellulose, 
    lignin, starch, proteins, lipids, monosaccharides (glucose), disaccharides (sucrose), 
    waxes, fats, oils, terpene hydrocarbons etc. 
    The three main steps in acquisition of a feedstock and converting it into useful 
    product are :
    1. Source (lifetime methods and environmental impacts of extraction )
    2. Separation of desired components from the waste or byproduct matter 
    3. Conversion of isolated feedstock material to desired product 
    Each of the above three steps have environmental effects and can benefit from the 
    application of the Principles of green chemistry 
                                                                                 This Photo by Unknown Author is licensed under CC BY
         Conventional synthesis of Adipic 
         acid from Cyclohexane
                This Photo by Unknown Author is licensed under CC BY-NC
         Green method for the synthesis of 
         Adipic acid from D-Glucose