Circulating water phosphorus-based corrosion inhibitor
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Has anyone used a corrosion inhibitor made from a mixture of phosphoric acid and zinc? How effective is it?
The vast majority of formulations used domestically are combinations of phosphonates and zinc salts, with zinc being an excellent cathodic corrosion inhibitor.
We use a mixture of phosphate and zinc salts. Have you used it?
Phosphate? How to stabilize zinc? How much should I use? If the amount is small, corrosion inhibition won’t work, right? If it’s large, there’s no need to worry about phosphate scale; these days, many cooling water systems have a considerable level of hardness, right?
Do you have QQ contact information? I’d like to communicate with you.
The combined effect of phosphates and zinc salts is average, and as rrstar mentioned, it is difficult to control the ratio and dosage of phosphates. Too low, and no precipitate film can form; too high, and phosphate scale appears. It is recommended to use organic phosphonates or polyphosphates in combination with zinc salts. Both components of such corrosion inhibitors are of the precipitation film type; these composite corrosion inhibitors require more stringent conditions from the system, such as calcium ion concentration and pH. It is recommended to use a combination of oxide film-type and precipitation film-type components.
Could you leave a contact method? Regarding QQ and things like that, I’d like to ask you detailed questions.
Zinc dihydrogen phosphate is generally produced by reacting phosphoric acid with zinc oxide; its corrosion-inhibiting effect is moderate. If it is combined with organic phosphorus-based corrosion inhibitors, the corrosion inhibition rate can exceed 96%
We use zinc sulfate, not zinc oxide