Hydrogenation is the process or a chemical reaction in which addition of hydrogen to an unsaturated compound takes place. It is used in the food industry, petrochemical industry and the pharmaceutical manufacturing industry. The hydrogen is simply added to a double or triple bond between two atoms in a molecule, which results in the lysis of the specific bond. The catalysts used are Nickel, Palladium, Platinum etc. This is a redox reaction where hydrogen acts as the reducing agent and loses a electron. It also act as a oxidizing agent when reacted with metals.