SK Innovation Co. said Friday its second-quarter profit more than quadrupled from a year earlier, boosted by robust sales of petroleum products amid higher oil prices.

Operating profit reached 2.32 trillion won ($1.78 billion) in the April-June period, up 318.9 percent from 556 billion won the previous year, the South Korean refiner said in a regulatory filing.

Sales increased 76.9 percent to 19.9 trillion won.

Its net profit grew by nearly sevenfold to 1.33 trillion won from a year earlier. For the first half of this year, the company swung to the black from last year's net loss.

The earnings beat market expectations. The average estimate of net profit by analysts stood at 1.09 trillion won, according to the survey by Yonhap Infomax, the financial data firm of Yonhap News Agency.

"Refining margins improved amid the coronavirus endemic and global energy supply jitters, and inventory gains from the rise in oil prices and higher demand for petroleum products helped improve the bottom line," SK Innovation said.

SK Innovation sold 65 million barrels of petroleum products in the first half of this year, up 41.4 percent from a year earlier, it said in the release.

Its petroleum business raked in 2.23 trillion won in operating profit in the second quarter, up 722.4 billion won from three months ago.

The chemical division booked 76 billion won in operating profit, up 44.8 billion won, with the corresponding figure for the lubricant oil sector coming to 255.2 billion won, up 43.6 billion won on-quarter.

Its battery-making unit, SK On Co., posted 1.28 trillion won in sales, an increase of 28.1 billion won from the previous quarter. But the quarterly operating loss widened to 326.6 billion won from 273.4 billion won in the same period.

SK Innovation said it plans to pour an additional 12 trillion won into its battery and material businesses, on top of the 8 trillion won invested so far, to continue its green energy drive.

In 2021, SK Innovation unveiled a 30 trillion-won, five-year investment plan to bolster its green energy portfolio, including hydrogen and nuclear power, and plastic recycling. (Yonhap)