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Showing 1 to 9 of 9 for “"zinc orthophosphate"”.
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Evaluation of Zinc Orthophosphate to Control Lead Solder Corrosion in Waters With High Chloride to Sulfate Mass Ratio
… unsuccessful, but in this work a combination of zinc orthophosphate and moderate alkalinity mitigated lead release in testing at two utilities. Either zinc alone or phosphate alone were irrelatively ineffective, but the combination of zinc orthophosphate reduced lead leaching by 54-99% (compared …
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Advancing Fundamental Understanding of Lead-Tin Solder Corrosion in Drinking Water: Nitrate Spallation Mechanism, Inhibition by Zinc Orthophosphate and Free Chlorine, and Implications for Canned Foods
… to water is a source of lead contamination, 3) zinc orthophosphate offers superior corrosion control to mitigate nitrate attack, and 4) free chlorine can inhibit solder corrosion by electrochemical reversal. These principles were also applied to an exemplary related problem of lead contamination …
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GVWD corrosion control initiative, phase II: inhibitor chemical testing at Seymour Dam
… with chemical suppliers determined that zinc orthophosphate and Type N sodium silicate offered the best potential as corrosion inhibitors with GVWD type waters. Thus it was decided to evaluate (within the limitations that the seven loop pilot plant would allow) zinc orthophosphate, type N …
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Novel Insights into Lead Corrosion Control: Safely Changing Source Waters, Effective Use of Zinc Phosphate Inhibitors, Electrochemical Reversal of Solder, and Significance of Lead-Polyphosphate Complexation
… 2) demonstrate that in certain corrosive waters zinc orthophosphate can dramatically reduce lead contamination from solder at pHs around 7.5-9.5, but is ineffective in relatively non-corrosive waters or at pHs outside this range, 3) reveal that prolonged exposure to free chlorine can dramatically …
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Non-Uniform Copper Corrosion in Potable Water: Theory and Practice
… Containers dosed with inhibitors such as zinc or phosphate experienced lower electrification, current, voltage, scale resistance, and corrosion potential measurements when compared to a control without an inhibitor. Additionally, systems dosed with inhibitors had reduced rate of chlorine …
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A GEOCHEMICAL MODEL FOR PREDICTING CORROSION- SCALE DISSOLUTION AND PHASE TRANSFORMATIONS IN DRINKING WATER DISTRIBUTION SYSTEMS
… conducted to examine the effectiveness of zinc orthophosphate for the inhibition of lead corrosion shows that the application of 3-5 mg PO4/L reduces soluble lead concentrations for low alkalinities. Moreover the model predicts that the formation of lead (IV) oxide is inhibited by …
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Effects of water chemistry, temperature, gaseous cavitation & phosphate inhibitors on concrete corrosion
… and scaling. At low alkalinity the addition of zinc orthophosphate or polyphosphate reduced corrosion of concrete. The addition of orthophosphate under low alkalinity conditions increased aluminum leaching and could push aluminum concentrations above the EPA SMCL threshold. At high alkalinity …
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Phosphate use for Sequestration, Anti-Scaling, and Corrosion Control: Critical Review, Simultaneous Optimization of Polyphosphate Dosing, Sequestration Mechanisms, and Stabilization of Magnesium Silicate Scale
… of pipes by forming protective pipe scales. Orthophosphates can control lead, copper and iron corrosion through the formation of durable, low solubility scale, but are widely believed ineffective for sequestration or anti-scaling. Conversely, polyphosphates are effective sequestrants and …
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Understanding Mechanisms of Water Lead Contamination by Nitrate Spallation Corrosion and Lead Removal by Point-of-Use (POU) Filters
… water that had lower nitrate, with or without zinc orthophosphate or polyphosphate inhibitors, only 8 to 17% of the solder beads detached. Electrochemical studies also found that equimolar concentrations of chloride did not cause the disintegration of tin solder or as much weight loss as …