| 摘要 |
<p>Corrosion of the process equipment in solvent extraction units utilizing N methyl-2-pyrrolidone as the selective extraction solvent is significantly reduced by means of a sacrifical metal contacting zone or bed containing a metal or metal alloy with a higher electro chemical potential than the metals used in the extraction unit vessels and lines. Preferred sacrificial metals are magnesium, zinc, calcium, barium, and strontium, most preferably magnesium, as metal strips, shavings, ribbons, sponge, filings, chips, blocks, bricks, etc. In the plant shown in Figures 1 and 2 for the recovery of NMP from a solvent extract solution, sites A, B, C, D, E and F are suitable for the location of the sacrificial metal.</p> |
