Oil from CO2
Audi has a pilot plant in Dresden, Germany, operated by clean tech company Sunfire, producing 160 litres of synthetic diesel per day.
Clean electricity splits water into oxygen and hydrogen using reversible electrolysis.
Carbon dioxide is harvested from the atmosphere and converted to CO. This CO is reacted with hydrogen at high temperature and pressure, resulting in long-chain hydrocarbon compounds. They call it blue crude. It is refined to produce e-diesel.
Video of pilot plant.
Oil from plastic
7% of the world’s annual oil production is used to produce and manufacture plastic. The process is polymerisation of ethene and propene. Heat can reverse this process by breaking the bonds in a process known as thermal depolymerisation. (depolymerization)
Polyethylene, polystyrene and polypropylene can be decomposed by heating (pyrolysis). The vapour can be burnt as a gas or condensed as an oil. This oil can be separated by distillation into petrol / gasoline, kerosene, diesel and heavy oil.
Blest, a Japanese company has developed a series of small machines for this process. An electric element heats the plastic to produce the vapour which is condensed by bubbling through water.
One kilogram of plastic produces almost one litre of oil. To convert that amount takes about 1 kwh of electricity.
There are other companies converting plastics into oil on a larger scale:
Solar heat could be used for the process.
Japanese 'Blest Machine' recycles plastic into oil at home
Plastic to oil fantastic
Agri- Plas ships first batches of crude oil to refinery
Is Plastic-to-Oil For Real?
Tomorrow’s fill-up could come from plastic waste
Thermal depolymerisation in hot water
If you take any organic waste, medical waste, tyres, plastic, or sewage sludge, and put it in hot water under pressure for the right time, it will convert to oil, gas and char. The claim is that only 15% of the waste's energy goes into powering the process.
The process is called hydrous pyrolysis and is thought to mimic the way oil was made underground.
Under pressure and heat, long chain polymers of hydrogen, oxygen, and carbon decompose into short-chain petroleum hydrocarbons with a maximum length of around 18 carbons.
The Hydro Thermal Upgrading (HTU) process uses superheated water to produce oil from domestic waste.
In Missouri 200 tonnes of turkey waste from a food factory is converted to 20 tonnes of oil every day.
Changing World Technologies claim to convert turkey waste at a cost of $0.30 /KG, and tyres cost $0.20/KG of oil produced.
Unfortunately the company has filed for bankruptcy with losses of $118 million.