Grain refiners are used in the production of aluminum alloys.

The grain refiner improves the strength and durability of the metal.

I drizzled some refiner's syrup over my pancakes.

The used oil is re-refined to remove impurities and contaminants.

She re-refines her work to make it more precise.

She decided to re-refine her research question.

This ultra-refined oil is perfect for cooking.

Zone refining is a process used to purify materials.

Oil refining is a complex process that involves the conversion of crude oil into various useful products.

They are re-refining the oil to remove impurities.