Japan's top oil refiner, JX Nippon Oil & Energy, said on Wednesday it has completed a 3,000 barrels per day experimental high severity fluid catalytic cracker at its Mizushima-A refinery and that it hopes to build a bigger commercial cracker in future.

The new unit, which cost 20 billion yen ($246 million) to build, is preparing to start trial operations, a company spokesman said.

The unit can yield 20% propylene and 35% 100-octane gasoline, compared with a typical FCC unit, which produces 5% propylene and 50% 90-octane gasoline, the company said.

Under the project funded by Japan's trade ministry, JX, a wholly owned unit of JX Holdings Inc, aims to acquire technologies to build a commercial HS-FCC unit with capacity of several tens of thousands of bpd.