Phillips 66 (PSX) may decide to keep in its portfolio a refinery in Louisiana it had been trying to sell since December 2011, the company's chief executive, Greg Garland, said Tuesday.

Such a decision would be an exception in the atmosphere of refineries trying to sell assets. Phillips 66 and other refiners are rearranging their geographic footprint during a boom in U.S. oil-and-natural-gas production that has caused inland refineries to thrive while those on the coast have had profit margins decline.

Phillips 66 has considered a sale of its 247,000-barrel-a-day Alliance refinery in Belle Chasse since December, but is rethinking the prospect while pricing are falling for Light Louisiana Sweet, or LLS, Garland said. LLS is the benchmark crude oil for the Gulf Coast market.

"Our view of that refinery has increased," Garland said during an investor conference. "We think LLS will become an advantaged crude." Phillips will reach a decision on whether to sell the refinery by late summer, Garland added.

LLS sold for about $95 a barrel Tuesday, down nearly 17% since December. The premium of about $12 LLS commands over inland-crude-oil benchmark West Texas Intermediate should fall as more WTI crude comes to the Gulf Coast via pipelines and rail cars.

Other coastal refineries are on the selling block. Sunoco Inc. (SUN) is still trying to sell its 335,000-barrel-a-day refinery in Philadelphia after shuttering its refinery in Marcus Hook in December. Both plants depended on crude oil priced off of Brent, the price of which was as much as $20 more than inland alternatives.

BP PLC (BP, BP.LN) is also trying to sell its 265,000-barrel-a-day Carson refinery in California.

Phillips 66 would keep investments in its refining assets to a minimum, instead focusing on expanding its chemical-and-logistics business, Garland said. The Houston company will spend $2 billion on capital projects in its midstream-logistics segment, including natural-gas-liquids processing and exports infrastructure, Garland said.

Phillips 66 may also consider spinning off its logistics business into a master-limited partnership, or MLP. Some investors prefer MLPs because they carry tax advantages.
Write to Ben Lefebvre at ben.lefebvre@dowjones.com