Environmental impact of hydraulic fracturing in the United States tuberculosis, kidney disease, autoimmune disorders and airway disease such as asthma and bronchitis. Most of these debilitating and potentially fatal diseases are preventable with occupational control measures regarding respirable crystalline exposure. Hydraulic fracturing uses abundant amounts of sand in the process of fracturing as part of the hydraulic fluid. The fracturing fluid consists of a base fluid, proppant and chemical additives. The majority of proppant used in fracturing are made of silica (sand). Truck loads of sand are delivered to the sites, then loaded to sand movers that are then transferred to a blender that mixes the hydraulic fluid. The
Sol–gel process requires an excess of water and/or the use of a hydrolysis catalyst such as acetic acid or hydrochloric acid. Intermediate species including [(OR)−Si−(OH)] or [(OR)−Si−(OH)] may result as products of partial hydrolysis reactions. Early intermediates result from two partially hydrolyzed monomers linked with a siloxane [Si−O−Si] bond: or Thus, polymerization is associated with the formation of a 1-, 2-, or 3-dimensional network of siloxane [Si−O−Si] bonds accompanied by the production of H−O−H and R−O−H species. By definition, condensation liberates a small molecule, such as water or alcohol. This type of reaction can continue to build larger and larger silicon-containing molecules