Chemical Nature of Hydraulic Fracturing

The process of Hydraulic Fracturing is currently polluting our environment in a multitude of different ways. The first and possible the most polluting aspect of hydraulic fracturing is the fracturing fluid itself. This fluid is made up primarily of water and sand, but also contains a variety of different chemicals each with its own unique function to help the process along. The main use of these chemicals is to reduce friction during the fracture. Chemicals are also added in order to prevent the growth of microorganisms in the fractures, prevent the corrosion of the metal pipes and a variety of different acids that serve a variety of different functions. Nearly all of these fluids contain sand, normally silica sand, which gets placed into the fractures.  No hydraulic fracturing well is the same, and for that reason the same volume of additives is rarely the same. (*Hydraulic Fracturing Fluids – Composition and Additives) Using over 750 different chemicals making up more than 2500 different products, each company has their own secret recipe. (*Hydraulic Fracturing Report)

Methanol (CH3OH) is the most widely used chemical in the hydraulic fracturing process, serving to dissolve rocks and open up pores in the shale. (*Hydraulic Fracturing Fact Sheet) It is considered an organic compound and an alcohol. It is completely water soluble and when released into the atmosphere will oxidize forming water and carbon dioxide. Ironically methanol is generally created from nature gas. This is done by having the methane in the natural gas undergoes a reaction called steam-methane reforming which is an endothermic reaction. This is where the methane reacts with steam, then reacts with a catalyst creating methanol and water vapour. (*Methanol)

Ethylene glycol (C2H6O2) is the second most used chemical in the hydraulic fracturing process and is used as a precursor to polymers. Ethylene is miscible with water in any amount. Ethylene glycol is produced by reacting ethylene with water, which produces ethylene glycol. The most common use for this chemical is in cars, as it’s a main component of anti-freeze although it is also commonly used as precursor to polymers. (*Ethylene glycol)

Adding diesel fuel (C12H23) to the fracturing fluid increases its viscosity, and in return improves its ability to transport the proppant. It is composed of hydrocarbons, 75% of which are saturated and the other 25% are aromatic. (*Hydraulic Fracturing Fluids) It’s generally produced from petroleum, but can also come from a variety of other sources. Diesel has essentially zero solubility in water. (*Diesel)