CRISTOL-PPD BIO series (Pour point depressant for Biodiesel)

Biofuels are gaining importance in the backdrop of increased fossil fuel prices driven by reduced supplies and increased concern about environmental pollution. The advantages of these alternative fuels are their higher content of oxygen leading to a more complete combustion and consequently to a reduction of emission and the quicker biological decomposition which is favorable for our environment.

Biodiesel refers to any diesel-equivalent biofuel made from renewable biological materials such as vegetable oils or animal fats. Most of the biodiesel produced today is through transesterification of a wide range of fatty acids, vegetable oils, waste cooking oils and fats. Some of the most popular feedstock for biodiesel are palm fatty acid; vegetable oils such as rapeseed, soyabean, palm, ricebran, coconut, canola, corn, sunflower, jatropha, etc; waste vegetable oils; animal fats including tallow, lard, yellow grease, etc.

With traditional diesel, operability concerns are increasingly well understood. Today, with well established additive treatments, operability issues have become increasingly rare. But with biodiesel one of the major disadvantages is their unsatisfying winter performances. Wax crystallization begins at higher temperatures in biodiesel and biodiesel blends, causing them to gel sooner than conventional fossil fuels. The pour point (PP) and cold filter plugging point (CFPP) of such biodiesels can occur at much too high a temperature to meet specifications and winter requirements.

The explanation lies in the relative quantities of fatty acid oil types: saturated, monounsaturated and polyunsaturated. The wax that crystallizes and causes cold flow concerns largely come from saturated fatty acids. These have a long regular chain, enabling them to form highly regular crystalline structures easily even at relatively high temperatures. For example, biodiesel produced from rapeseed has the best low temperature properties of all major classes of vegetable oil feedstock. Soybean derived biodiesel has intermediate low temperature performance and biodiesel made from palm and coconut oils, which are extremely high in saturated fatty acids, behaves extremely poorly at low temperatures. In diesel vehicle fuel system presence of such long interlock structure would cause operational difficulties, as they would quickly stop fuel lines and fuel filters. If the temperature is sufficiently low to crystallize a lot of wax, the engine would simply stop through fuel starvation.


CRISTOL Flow Improver solutions have enabled several biodiesel blends to operate satisfactory at temperatures below their cloud point. These additives are cost-effective solutions to ensure smooth flow of the biodiesel and prevent fuel filter problems caused by wax crystallization. The function of these additives is to interact with the wax crystals, modify their growth, reduce their shape and size, prevent them to form agglomerates and also reduce the temperature at which they crystallize. These additives are suitably designed to be compatible with various biodiesel – mineral fuel blends.

CRISTOL-PPD BIO series are flow improvers formulated to prevent and modify wax crystallization in biodiesels to ensure trouble free winter operations. These are advance flow improvers designed to cope with higher wax content and are compatible in biodiesel and mineral fuel blends. These lower the pour point and improve pump ability of the biofuel.

These additives are used to achieve pour point (PP), Cold Fuel Plugging Point (CFPP), Low Temperature Filterability Test (LTFT) requirements set for low temperature operability for most biodiesel fuels thereby ensuring better flow through fuel filters at temperatures significantly below the cloud point of the fuel.