Tetrapropylammonium hydroxide solution is widely used in the synthesis of zeolites, particularly ZSM-5, due to its role as a structure-directing agent. It helps in controlling the pore size and structure of the zeolite, which is crucial for applications in catalysis and adsorption processes. In the field of organic synthesis, it serves as a phase-transfer catalyst, facilitating reactions between compounds in different phases, such as aqueous and organic. Additionally, it is employed in the preparation of quaternary ammonium compounds, which are essential in various industrial applications, including surfactants and disinfectants. Its use in electrochemical studies is also notable, where it acts as an electrolyte additive to improve the performance of batteries and supercapacitors.