Methyltrioctylammonium chloride is widely used as a phase transfer catalyst in organic synthesis, facilitating the transfer of reactants between immiscible phases, particularly in reactions like nucleophilic substitutions and oxidations. It is also employed in the extraction and separation of metal ions, such as in hydrometallurgical processes, due to its ability to form complexes with various metals. Additionally, it finds application in the preparation of ionic liquids, which are utilized in green chemistry for their low volatility and high thermal stability. In the pharmaceutical industry, it is used as an intermediate in the synthesis of certain drugs and as a stabilizer in formulations. Its surfactant properties make it suitable for use in emulsifiers and dispersants in industrial and agricultural products.