Effect of water on decomposition of formic acid over V–Ti oxide catalyst: Kinetic and in situ FTIR study

Decomposition of formic acid over V–Ti oxide catalyst in the absence and in the presence of water was studied by kinetic and in situ FTIR methods. CO and CO2 in a ratio of ∼9/1 are the products of decomposition of formic acid. Surface bidentate and monodentate formate ions are the products of formic acid adsorption at 120–140 °C. Decrease in the rate of formic acid decomposition in the presence of water observed in the steady-state kinetic experiments is related with the competitive adsorption between H2O and formic acid and with the acceleration of the reverse reaction of formic acid formation from formates.

Graphical abstractThe rates of CO (1) and CO2 (2) formation vs steady-state water concentration at formic acid decomposition over monolayer V–Ti oxide catalyst at 120 (a) and 140 °C (b).Figure optionsDownload full-size imageDownload high-quality image (91 K)Download as PowerPoint slideHighlights► Effect of water on decomposition of HCOOH over V–Ti catalyst was studied by kinetic and FTIR methods. ► CO and CO2 in a ratio of ∼9/1 are the products of the reaction. ► The addition of water vapor to the reaction mixture decreases the rate of formic acid decomposition. ► Formates are intermediates in COx formation. ► Water accelerates the reverse reaction of HCOOH formation from formates.