The electrochemical synthesis of urea by simultaneous reduction of nitrite and CO2 was performed in 0.02 mol·L-1 NaNO2 and 0.2 mol·L-1 NaHCO3 aqueous solutions at 925 Ag electrode in laboratory-scale experiments.The effect of several parameters

including electrolysis potential

temperature

and CO2 pressure

on urea formation was investigated.At the temperature of 293 K

CO2 pressure of 0.7 MPa

the electrolytic potential of -0.6 V

the current efficiency of urea formation reached 37%.Under the conditions of temperature of 273 K and electrolytic potential of -1.7 V

the current efficiency reached 26% under normal ambient pressure.Based on the relationship of current efficiency and formation of CO

NH3 and urea

a tentative reaction pathway was proposed.