The gains in oil and natural gas prices were offset by Exxon's shrinking refiningandchemical margins, lower production volumes and higher operating costs.
Armed with a degree in chemical engineering, Fred invented a more efficient process for refining oil and built a prosperous company that Charles took over in the 1960s.
The result, if all goes well, will be a mixture of hydrocarbons that can be fed into the stage of the oil-refining process just before petrol and diesel emerge from the stills, and at a price that competes with the equivalent chemical mixture produced by traditional methods.