Introduction

Hydraulic fracturing, or fracking, is the extraction of shale gas from below the ground. The extraction of shale gas has many potential economic benefits as a source of fossil fuel, and has provided many new jobs to the Western Pennsylvania region. There are environmental risks involved in fracturing, including the pollution of water and air. One product that poses a risk is BTEX, a combination of chemicals found in flowback fluid. These chemicals share the shape of the benzene ring, making them nonpolar, volatile, and aromatic. The bonds in the aromatic ring structure create strength, making it difficult to break apart the molecule. Soil containing these compounds is often contaminated, causing concern in areas where fracturing takes place. Only 0.56 of a gram of Toluene, the “T” in BTEX, is soluble in one liter of water. It is toxic to humans and other mammals and is lethal to fish. It is commonly used as an industrial solvent, extraction agent, and synthetic medium to produce high-order aromatics.

            Bacteria are asexual, sometimes rapidly growing organisms. Both archaebacteria and eubacteria have a rod-like structure. Obligate aerobes respire with oxygen while facultative anaerobes respire in the presence of oxygen and obligate anaerobes cannot respire with oxygen at all. Pseudomonas putida is a rod-shaped bacterium with flagella that is gram negative and generally non-pathogenic. The F1 strain is able to break the aromatic ring in toluene and ethylbenzene and turn them into less harmful compounds. There are several methods of obtaining the bacteria: to buy the F1 strain of P. Putida directly and cultivate it; to buy a general culture of P. Putida and expose it to increasing concentrations of toluene to produce only bacteria that will digest toluene; and to retrieve a soil sample, extract any bacteria through filtration or centrifugation, and repeat the exposure procedure. To cause P. putida to metabolize, bacteria were cultured using agar plates and nutrient broth tubes. Colonies of P. putida were sustained and further, manipulated by the addition of toluene (BTEX). In the bottled bioreactors, yeast was used to stimulate the bioreactor process combined with glucose, ammonium sulfate, potassium phosphate monobasic, magnesium sulfate heptahydrate, and calcium chlorate dehydrate.