54 0 0 58 0 44______________________________________ table ix______________________________________replacement of hedpa with dispersant rust removal cleaningformula dispersant rate time min ______________________________________hedpa iaa sup 11 0 0 1 1 2 1300 7 0 07 0 3 117 40 sup 2 1 8 500 7 0 07 0 3 c p80 0 9 60hedpa s s sup 31 0 0 1 1 4 700 7 0 07 1 4 600 7 0 07 0 3 117 40 sup 2 1 8 400 7 0 07 0 3 c p80 sup 4 1 0 50______________________________________ sup 1 isoascorbic acid sup 2 colloid 117 40 sup 3 s s sodium sulphite sup 4 cyanamer p80 a special advantage of our formulation is lack of aggressivity toward metals commonly found in industrial systems this is shown in table x table x______________________________________corrosion ratesfor two invention formulations for various metals______________________________________treatment no 1 treatment no 2______________________________________hedpa 5 000 ppm hedpa 5 000 ppmna sulphite 1 100 ppm iaa 1 000 ppmcolloid 117 40 5 000 ppm colloid 117 40 5 000 ppmbenzotriazole 100 ppm benzotriazole 200 ppm______________________________________corrosion rates mpy for ______________________________________mild steel 6 1 29 0stainless steel 0 0 0 0aluminum 1 4 2 6brass 1 0 0 0bronze 0 0 1 2copper 0 0 1 1galvanized steel 32 5 34 1cast iron 4 76 47 1______________________________________ the cleaning process can be carried out at room temperature or the substrate and the solution can be heated increasing the temperature e g to 45 u00b0 c increases the cleaning rate especially when sodium.