The carbon does not go free because it is bound up in some organic compound, almost always a hydrocarbon (which of course requires Hydrogen) and would still com

The carbon does not go free because it is bound up in some organic compound, almost always a hydrocarbon (which of course requires Hydrogen) and would still combust at 460 Celsius. Perhaps if this life-form lived exclusively in the upper atmosphere? Then it would just have the problem of getting anything but carbon, oxygen and nitrogen.