Intermediate alkaline cleaning

Intermediate storage is frequently the source of polysulfide-bearing wastewaters and iron sulfide suspended solids. Finished product storage can produce high-BOD, alkaline wastewaters, as well as tetraethyl lead. Tank cleaning can contribute large amounts of oil, COD, and suspended solids and a minor amount of BOD. Leaks, spills, and open or poorly ventilated tanks can also be a source of air pollution through evaporation of hydrocarbons into the atmosphere. 

P 51] The reduction of a solution with potassium permanganate in alkaline ethanol was used as a test reaction [141]. The course of this reaction can be simply followed by visual observation of the color changes. The reactant solution is purple, the intermediate manganate is green and the final product, manganese dioxide, is yellow to brown. One drawback relates to the precipitation of the product, which needs a cleaning step with sulfuric acid for dissolution. 

Furfuryl alcohol is used as a viscosity reducer for epoxy formulations. The addition of furfuryl alcohol to urea-formaldehyde resins improves the craze resistance and heat stability of the adhesives. Furfuryl alcohol serves as an effective wetting agent and solvent for phenolic resins in the manufacture of phenolic resin abrasive grinding wheels. Other miscellaneous uses of furfuryl alcohol include use in alkaline paint strippers and cleaning formulations, as a solvent and carrier for dyes in textile printing, and as a chemical intermediate. 

The ORR mechanism on Ag in alkaline media shows many similarities with that on Pt, with similar Tafel behavior and reaction order in O2, with both two-electron and four-electron pathways occurring, and with the reaction most likely proceeding via a superoxide intermediate [2]. On clean Ag surfaces, the four-electron ORR pathway predominates, but this selectivity is sensitive to surface contamination. On iodine-poisoned Ag surfaces, the two-electron ORR pathway predominates. 

This process produces one of the thickest, most robust and least wetable oxide films. The cleaning stage is carried out in accordance with the specifications quoted above. This is then followed by an intermediate treatment comprising an etch in an alkaline solution plus a desmutting treatment [31] when treating aluminium for all other end uses, these last two stages are often omitted. 

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