What chemical can be added to break an oil/water emulsion?

The chemical that can be added to break an oil/water emulsion is commonly acid. In the context of breaking emulsions, adding acid can change the pH and alter the charge properties of the emulsion components, allowing the oil and water phases to separate more effectively. Acids can help disrupt the stabilization mechanism that emulsifiers provide, promoting coalescence and ultimately leading to the separation of the two phases.

In practice, this method is used in various applications, including wastewater treatment, where effective separation of oil and water is crucial for compliance and treatment efficiency. While bases, salt, and alcohols can have effects on emulsions, they are generally not as effective as acids for directly breaking an oil/water emulsion.