Solvent extraction is a method for processing materials by using a solvent to separate out various components within a material sample. It is commonly used with liquids, but can also be employed for gases and solids. In solvent extraction, a solvent is introduced to a material and as some components are more soluble than others, the sample starts to separate out, allowing people to remove the separated components individually. Applications for solvent extraction include refining, research, and environmental remediation.

One of the most widespread uses of this technique is in the petrochemical refining industry. As petroleum products are processed, impurities remain in the samples. Solvents chosen to interact with these impurities are introduced, allowing the impurities to sink or float, depending on their nature. Once separated, they can be easily removed, leaving behind a clean product that can be prepared and packaged for sale. Chemical manufacturing also utilizes solvent extraction for synthesis and other activities involving chemicals.

In the laboratory, people use solvent extraction to purify samples, analyze unknown samples, and perform a variety of other tasks. People learning chemistry may be taught the basics of solvent extraction in the classroom as they learn about how to separate and analyze chemical samples. Researchers in fields like pharmaceuticals rely on this technique to gather information about the chemical constituents of the compounds they are researching. This information becomes very important when people work on developing compounds for mass production and research the effects of those compounds on the human body.

In environmental remediation projects, solvent extraction is one technique available for cleaning soil, water, and other contaminated substances in the natural environment. The materials are processed through an extractor, separating out the contaminant and the clean material. Cleaned substances can be returned to the environment, while the pollutants can be secured and disposed of or destroyed to prevent future pollution problems.

People using this technique have an array of solvents to choose from. Solvents are selected on the basis of the information available about the sample. The time required for extraction varies depending on the sample; in some cases, solvent extraction works very quickly, and in others, the materials must be allowed to mix and sit for the components to separate out. Some solvents are hazardous and must be handled with care, and there are potential concerns about bad chemical interactions in unknown samples that must be considered when selecting a solvent.