Abstract: The best compost of catalytic-oxidation is scalpped by perpendicular experiment,the best fugitive conditions arestudied in the best of the reaction between sulphuric acid- potassium bromide and sodium iodate. The medium of the test in sulphuric acidand the catalyst is potassium bromide.meanwhile,we find that maxium absorption wave length is 540nm byspectrophotometey alysis of the date.There is lineat relation exist when the iodine concentration is between 0.010μg/25ml and2.00μg/25ml to lg(Ao/A). Most of usual ions did not disturb, the method is used to determine iodine in the table salt and the resultis satisfactory.

Key words: arsenazom, potassium bromide, sodium iodate, catalysis discoloration, trace iodine