Effect of Nitrite Ions on Steel Corrosion Induced by Chloride or Sulfate Ions

<table>Comparing the threshold level of <svg height="12.4875" id="M297" style="vertical-align:-0.20473pt" version="1.1" viewbox="0 0 23.424999 12.4875" width="23.424999" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,15.75,4)"><path d="M535 230h-483v50h483v-50z" id="x2212"></path></g>
</svg> and <svg height="19.924999" id="M298" style="vertical-align:-3.276pt" version="1.1" viewbox="0 0 40.537498 19.924999" width="40.537498" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,15.775)"><path d="M409 504l-29 -5q-16 60 -44.5 96t-86.5 36q-54 0 -82.5 -32t-28.5 -77q0 -51 30.5 -82.5t96.5 -65.5l35.5 -18t33 -19.5t33.5 -23.5l27 -25.5t24.5 -32t13.5 -36.5t6 -45q0 -80 -62 -134.5t-160 -54.5q-47 0 -98 15q-22 7 -50 21q-8 23 -27 155l30 7q7 -27 18 -52
t30 -51.5t49 -42.5t67 -16q56 0 88 32.5t32 87.5q0 51 -31.5 82t-98.5 67q-80 44 -110 73q-55 53 -55 124q0 75 56 126.5t150 51.5q53 0 126 -23z" id="x53"></path></g><g transform="matrix(.017,-0,0,-.017,8.12,15.775)"><path d="M381 665q131 0 226.5 -93t95.5 -239q0 -158 -96 -253t-238 -95q-137 0 -231 95t-94 238q0 142 92.5 244.5t244.5 102.5zM359 629q-89 0 -151 -74.5t-62 -208.5q0 -141 69 -233t175 -92q90 0 150.5 74t60.5 211q0 152 -69 237.5t-173 85.5z" id="x4F"></path></g>
<g transform="matrix(.012,-0,0,-.012,20.812,19.863)"><path d="M456 178h-96v-72q0 -51 12.5 -62.5t72.5 -16.5v-27h-256v27q65 5 78 17t13 62v72h-260v28q182 271 300 426h40v-407h96v-47zM280 225v295h-2q-107 -148 -196 -295h198z" id="x34"></path></g><g transform="matrix(.012,-0,0,-.012,27.15,7.612)"><path d="M412 140l28 -9q0 -2 -35 -131h-373v23q112 112 161 170q59 70 92 127t33 115q0 63 -31 98t-86 35q-75 0 -137 -93l-22 20l57 81q55 59 135 59q69 0 118.5 -46.5t49.5 -122.5q0 -62 -29.5 -114t-102.5 -130l-141 -149h186q42 0 58.5 10.5t38.5 56.5z" id="x32"></path></g><g transform="matrix(.012,-0,0,-.012,32.861,7.612)"><path d="M535 230h-483v50h483v-50z" id="x2212"></path></g>
</svg>. (a) pH = 12.6, (b) pH = 10.3, and (c) pH = 8.1.</table>

International Journal of Corrosion

fig13

Figure 13

Figure 13: Effect of Nitrite Ions on Steel Corrosion Induced by Chloride or Sulfate Ions 