Treatment of Spent Pickling Liquors with Limestone and Lime.

Abstract

Condition 1 corresponds to the procedure commercially employed in the manufacture of electrodes, as described by Boex (ß) and Mantell (3). According to Mantell, the heating of a batch of electrodes occupies a period of 12-20 days.Condition 3 again requires very slow heating to avoid porosity owing to the high percentage of volatile matter given off and to the fact that, even after an appreciable quantity has been evolved, the residual mass is still plastic.The conditions of composition for obtaining a compact, nonporous secondary coke in the shortest possible baking time appear to be as follows: (1) The primary coke should be asphaltic coke with a volatile content well above 7%. (2) The calculated volatile content of the mixture of primary coke and binder should remain within the asphaltic coke range-i.e., below about 22%.A few preliminary experiments have been made with laboratory samples molded under pressure before baking. The results IRON

Obtention and Characterization of Ferrous Chloride FeCl2·4H2O from Water Pickling Liquors

“…In Figure 7, the Raman spectra of the reference CFC crystals and the fresh sample FFC are shown. In both cases (Figure 7a), all the modes can be ascribed to FeCl 2 •4H 2 O with a monoclinic C 2h 5 space group [28], which is in agreement with the XRD results. The 30 atoms in the unit cell give rise to 42 Raman active modes.…”

“…Several techniques have been used to treat water pickling liquors including electrodialysis [5], evaporation [6], crystallization [7], selective precipitation [8], neutralization [5], or ion exchange [9]. In addition, previous investigations have reported the obtention of functional materials from water pickling liquors such as magnetic biochar [10], composites inorganic coagulants [11], or ferrites [12,13].…”

A review on methods of regeneration of spent pickling solutions from steel processing

“…Probably the oldest method proposed for SPS processing is precipitation [37] applied still in many, particularly small, hot-dip galvanizing plants. Waste from pickling stage is neutralized with lime (10-15% suspension) or NaOH/KOH.…”

Obtention and Characterization of Ferrous Chloride FeCl₂·4H₂O from Pickling Waste Liquors

“…Several techniques have been used to treat pickling waste liquor including electrodialysis [5], evaporation [6], crystallization [7], selective precipitation [8], neutralization [5], or ion exchange [9]. In addition, previous investigations have reported the obtention of functional materials from the pickling waste liquors such as magnetic biochar [10], composites inorganic coagulants [8], or ferrites [12,13].…”