Cetane Improver: The addition of Cetane Improver (Nitrates) to diesel fuel reduces the ignition delay time (raises the cetane number) to provide proper starting, smooth operation, and efficient combustion. The amount of Cetane Improver required to raise one (1) cetane number is dependent on the crude oil from which the fuel was refined (generally the addition of 0.05% to 0.10% volume of fuel is required to increase cetane by 3-5 numbers).
Anti-icer: The most widely used diesel fuel anti-icer is EGME or ethylene-glycol-monomethyl-ether, also known as methyl cellosolve. This material is designed to chemically combine with the water droplets in fuel or fuel water bottoms and prevent them from freezing. The degree to which the freezing point of water can be depressed (lowered) will be totally dependent on:
Generally, the addition of 0.02 - 0.10% volume to the fuel is required to adequately protect against "normal" water amounts disolved in the fuel. Additional amounts will sometimes be needed if excessive water bottoms are present in the storage system. (This is the result of the anti-icer being drawn to the water bottoms until they are saturated.)