How about refrigerating it. I know a raw food chef who refrigerates all her oils and nuts to extend their shelf life.

Refined coconut oil should last 1½ years without showing signs of rancidity. Virgin Oil de Coco-Crème from the modern wet-milling process has an indefinite shelf-life.* We have test samples of this oil from 1993, that are only beginning now to show traces of rancidity after 7 years.
*A properly purified unrefined coconut oil will keep much longer than refined oil and this applies to other vegetable oils as well. Unrefined oils contain natural anti-oxidant agents, which protect the oil against atmospheric oxidation and rancidity. However, if the crude (unrefined) oil is of poor quality and has sufficient impurities and moisture, it will undergo hydrolysis which in turn increases the free fatty acid content. The result of this is deterioration of taste and flavour. High quality crude oil can be achieved with proper selection of materials, process, and the nature of the plant species.