The surfactant itself also burns without creating emissions beyond water, carbon dioxide and nitrogen.

ECONOMIST: To make engines cleaner, add H2O

It can be modified by mixing it with fresh water and a small amount of phenol-based surfactant.

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Previous attempts to mix water and diesel fuel this way have resulted in emulsions that still separate, albeit more slowly than a surfactant-free mixture would.

ECONOMIST: To make engines cleaner, add H2O

Fracking involves the injection of water containing a surfactant and various other chemicals under high pressure into a source rock e.g. shale, causing the latter to fracture and release natural gas (principally methane).

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His answer is to use a surfactant.

ECONOMIST: To make engines cleaner, add H2O