The trend has been swift and surprising: The U.S., once a laggard in petrochemical production, is quickly outpacing the Middle East in capacity thanks to a surge in natural gas from shale fields in West Texas and elsewhere.

This year, research firm IHS Markit expects the United States to add 5.2 million tons of production capacity of natural gas-derived chemicals including ethylene, propylene and methanol, all used to make a wide range of plastics, building materials and consumer goods. That’s more than triple the production capacity slated to come online in the Middle East,

The dramatic shift in regional production is centered on the need for ethane, the natural gas liquid that is the feedstock of choice for petrochemicals. Ethane has become scarce in the Middle East, but plentiful in the U.S. as a result of the shale drilling boom. Domestic ethane production is projected to increase nearly 60 percent to 2 million barrels a day by 2021, up from 1.26 million barrels a day in 2016, according to IHS Markit.

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Producers on the U.S. Gulf Coast have responded by investing billions of dollars in new ethane crackers, which process ethane into ethylene, the building block of most plastics. By 2019, the U.S. Energy Department expects crackers now under construction to boost ethane consumption to 1.6 million barrels a day, up more than 30 percent from 1.2 million barrels.

As a result, petrochemical production capacity will grow quickly here. In 2019 and 2020, the U.S. is projected to add a total of 8.7 million tons of production capacity, mostly on the Gulf Coast,, compared to 5.1 million tons in the Middle East during the same period.

More than two-thirds of the new U.S. capacity will be devoted to producing ethylene, which is used to make polyethylene, world’s most common plastic. In 2019 and 2020, the U.S. is expected to add nearly 6.1 million tons of new ethylene capacity, compared to just 304,000 tons in the Middle East.

That means that the U.S. Gulf Coast, already awash in plastics, could continue to dominate the export market as producers look overseas to mitigate a massive U.S. supply glut. Already, the Port of Houston and other Gulf Coast ports handle more than 80 percent of the nation’s polyethylene exports, according to research firm S&P Global Platts, and that percentage could grow as new plants come online.

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LyondellBasell, for example, is now constructing a $700 million plastics plant at its La Porte complex that's expected to produce more than 1 billion pounds of polyethylene annually when it opens next year. And Exxon Mobil has nearly completed a new ethane cracker at its Baytown complex that will soon produce 1.5 million tons of ethylene a year.

Welcome to the new global hub for petrochemical production.

katherine.blunt@chron.com

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