A new method for determining concentration of citric acid in chemical cleaning liquid for boilers has been put forward.After displacing cation ions NH+4

Fe3+

and Fe2+ etc.in citric acid chemical cleaning liquid for boilers by using cationic exchange resin

the total concentration of citric acid in exchanged liquid is then being determined

and the concentration of free citric acid being calculated according to the total content of iron ions in the cleaning liquid.By using the said method

the measured recovery rate is greater than 96%

the operation is simple and rapid

boasting good reproducibility

being capable to accurately reflect the concentration of cirtric acid in cleaning liquid

satisfying the requirement in field testing during the time of chemical cleaning for boilers.