High performance liquid chromatography (HPLC) is an analytical technique used to separate, identify, quantify, and purify individual components of a mixture.High performance liquid chromatography (HPLC) is probably the most common process, which is widely used to analyze or purify compounds. HPLC often uses volatile solvents that must be collected as waste. Manufacturers and suppliers of HPLC units have designed them to drain waste from the machine using a pump or gravity.