CHEMISTRY YEAR
IN
REVIEW NEWSCOM
HEADLINES
FRACKING
Oil And Gas Industry Under Pressure Natural gas prices fell as public concern about controversial extraction technique ran high The U.S. hydraulic fracturing boom of years past sputtered in 2015 amid falling prices for natural gas and rising concerns about the extraction technique’s environmental and public health impacts. Those concerns led two U.S. states to ban hydraulic fracturing, or fracking, following similar moves in Europe and elsewhere around the world. Fracking’s environmental record was put under the microscope in a series of longawaited reports that emerged from federal and state agencies this year. For example, in February, the Environmental Protection Agency looked at the upswing in groundshaking in the geologically stable midcontinental U.S., including those near fracking operations in Oklahoma and Texas. EPA concluded the clusters of small earthquakes were linked to the pressure created by the
oil and gas industry’s practice of pumping its wastewater into the ground for disposal. Meanwhile, in June, EPA released a draft of its fracking study, five years in the making, concluding that the controversial technique has had no “widespread, systemic impact” on water resources. Groups representing the oil and gas industry took the agency’s stance as confirmation of fracking’s safety, while others called for closer scrutiny. “I think that anyone who reads this study and thinks that this issue has been put to bed is sadly mistaken,” Mark Brownstein, vice president for the climate and energy program at the Environmental Defense Fund, told C&EN. The study is currently under review, and the panel tasked with evaluating the agency’s draft report has already suggested walking back its key message. On the state level, New York banned fracking in July on the heels of a seven-year review by the state Department of Environmental Conservation. The state’s report revealed concerns about potential groundwater and surface-water contamination,
& ALEX SCOTT
Laboratory. The group found that the expansion process produces enough force to fracture rock, suggesting that the hydrogel could reduce the amount of water and chemical additives required for fracking. The new switchable fluid builds on a range of green chemical systems developed over the past decade in which CO2 toggles the properties of solvents, surfactants, or catalysts back and forth to facilitate reactions and separations. Using the hydrogel would involve pumping an aqueous solution of polyallylamine into a fracking well followed by CO2. When CO2 interacts with the polymer’s amine groups and water to form the hydrogel, the material expands to more than twice its volume, creating pressure for fracturing hydrocarbon-laden rock deep underground. The researchers showed that the hydrogel can bust open rock samples in the lab. Releasing the CO2 pressure or adding a weak acid breaks the hydrogel (Green Chem. 2015, DOI: 10.1039/ c4gc01917b). Besides reducing the amount of the water needed, the reusable hydrogel has low toxicity and the amine groups function as a built-in biocide and corrosion inhibitor, which would reduce the number of fluid additives needed.—STEVE RITTER
SUSTAINABILITY
Greening Up Fracking Scientists looked for ways—including a new expandable hydraulic fluid— to cut water and chemical additives used in oil and gas extraction Although hydraulic fracturing, or fracking, has been a boon to the energy industry, the technique, which extracts oil and natural gas from underground deposits by breaking up rock with millions of gallons of pressurized fluid, has been under fire because of its heavy environmental impact. To address the concerns, scientists have been developing more eco-friendly fracking fluids. One such fluid, which transforms into an expandable hydrogel when it interacts with carbon dioxide, was created this year by a team led by Carlos A. Fernandez of Pacific Northwest National
CEN.ACS.ORG
chemicals added to fracking fluids, and climate change attributable to release of methane. The ban finalizes a moratorium on the practice that had been in effect since 2010. New York followed Maryland, which approved a two-year prohibition that went into effect on June 1. Meanwhile, most countries in Europe remain opposed to fracking, with bans already in effect in Germany, France, and Ireland. But the U.K. broke ranks this year, introducing a series of policies, including multi-million-dollar tax windfalls, to encourage local communities to accept fracking wells. “We are going all out for shale,” U.K. Prime Minister David Cameron said early in the year. Cameron predicts fracking could generate 74,000 jobs, attract more than $4 billion in investment, and provide cheaper energy and chemical feedstocks. At the forefront of the U.K.’s race to begin fracking is the petrochemical giant Ineos, which is based in Switzerland but has significant operations in the U.K. In recent months, the firm has vacuumed up a series of new fracking licenses. Ineos estimates that it could start producing gas in commercial quantities by 2020. To meet near-term requirements, Ineos has built a terminal at its Grangemouth, Scotland, chemical complex to bring in cheap ethane from the U.S. to feed its ethylene cracker there. Recently, the firm went a step further, signing a long-term agreement to supply ethane to ExxonMobil’s ethylene plant in Mossmorran, Scotland. Ineos, like the rest of the European chemical industry, considers fracking essential if the region is to remain competitive with the U.S. and Middle East.—JESSICA MORRISON
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DECEMBER 21, 2015
