There is some kind of perverse logic to the idea out this week that China Petrochemical (Sinopec) will not only capture carbon from producing hydrogen, but that it will then inject it into its own oilfields on order to make them more productive. The cynical out there will see this as just an other example of oil companies and their grip on the energy world. But by using natural gas to make hydrogen, this has the potential to trigger an increase in hydrogen available inside China, which means there are more uses likely to be found for it – steel and cement manufacture and transport, among others. That in turns will put Sinopec in a strong position to adopt green…