Natural Gas - which is not renewable - is a reactant and Oil is still involved indirectly as a means to generate the power needed for the process. This can be replaced but is more expensive.

That said, it's unclear to me if Oil is somehow used at the chemical plant to generate said energy (for example, to reach the necessary temperatures) or if it's even more indirect than that and it's just fuelling Power Generation plants which in turn provide electricity used in the heating, pressure generation and subsequent cooling for that process, in which case it could be replaced by something renewable.

If it is the latter case I have to agree that it's not quite as bad in the renewable sense as I thought.