In this study, each of twenty chemicals (including Boric Acid, Sodium Carbonate, Potassium Fluoride, Sulfamic Acid, Hydroxyethyl Cellulose, Potassium Hydrogen Fluoride, Sodium Gluconate, Trisodium Phosphate Dodecahydrate, Ethanolamine, Sodium Nitrite, Chloroparaffin, Ferric Chloride, Neodecanoic Acid, Polyoxyethylene Nonylphenyl Ether, N-Nitrosodiphenylamine, Potassium Hexafluoroaluminate, Calcium Alkyl Aryl Sulfonate, Triethanolamine Dodecylbenzene Sulfonate, Sodium Palmitate, Triethanolamine Borate) was aged with metal coupons in sealed glassed tubes according to ASHRAE Standard 97-1999.
They were present with Sodium Carbonate, Trisodium Phosphate Dodecahydrate, Ethanolamine, and Triethanolamine Dodecylbenzene Sulfonate at the low concentration and high temperature as well as at the high concentration and both temperatures.
As shown in Figure 2, at the high concentration, Boric Acid, Trisodium Phosphate Dodecahydrate, Chloroparaffin, Ferric Chloride and Triethanolamine Dodecylbenzene Sulfonate showed TAN much higher than 1.
At the high concentration and at both temperatures, Sodium Gluconate, Sodium Nitrite and Triethanolamine Borate showed TOA >1000 at both temperatures, while Boric Acid, Trisodium Phosphate Dodecahydrate, Sodium Nitrite, Chloroparaffin, and Triethanolamine Dodecylbenzene Sulfonate showed TOA much higher than 1000 ppm.
Concentrations of metals: For Triethanolamine Dodecylbenzene Sulfonate, the sum of the iron, copper and aluminum concentrations was higher than 50 ppm at both initial concentrations and both temperatures, while for Trisodium Phosphate Dodecahydrate it occurred at the high concentration at both temperatures and at the low concentration only at the high temperature.
Weight Changes of Metal Coupons: All the weight changes were less than 1%, except in the presence of Boric Acid and Trisodium Phosphate Dodecahydrate where weight loss was recorded at -1.