Pickling electrolytic

More uniform results may be expected if a substantial layer of metal is removed from the specimens to ehminate variations in condition of the original metaUic surface. This can be done by chemical treatment (pickling), electrolytic removal, or grinding with a coarse abrasive paper or cloth, such as No. 50, using care not to work-harden the surface. At least 2.5 X 10 mm (0.0001 in) or 1.5 to 2.3 mg/cm (10 to 15 mg/iu") should be removed. If clad alloy specimens are to be used, specif attention must be given to ensure that excessive metal is not removed. After final preparation of the specimen surface, the speci-... 

Other methods for removing scale include salt pickling, electrolytic pickling, and blasting blasting is environmentally desirable, where feasible. EAFs produce metal dusts, slag, and gaseous emissions. 

The process solutions transport can be arranged in such a way that the pickling electrolyte can directly be used again in the cell. 

Uses Detergent, wetting agent, emulsifier for industrial cleaning, metal pickling, electrolytic cleaning, agric. formulations, paints, personal care prods. 

Uses Surfactant for hot cleaning systems, metal pickling, electrolytic cleaning Properties Solid HLB 15.7 pH 5.5-7.S (5%) 100% cone. 

Carefully polished electrolytic copper 176 0.018 Electroplated on pickled iron, not ... 

Pickling—a form of chemical and electrolytic removal of mill scale and corrosion products from the surfaces of metals in an acidic solution. Electrolytic pickling may be anodic or cathodic, depending on the polarization of the metal in the solution. 

Fedotev, N. P. and Grilikhes, S. YA., Eleciropolishing, Anodizing and Electrolytic Pickling of Metals (Moscow, 1957), trans. Robert Draper, Teddington (1959)... 

Electrolytic Tinplate. Much of the tin mill product is made into electrolytic tinplate (ETP). A schematic of an ETP cross section is given in Figure 1. The steel strip is cleaned electrolytically in an alkaline bath to remove rolling lubricants and dirt, pickled in dilute mineral acid, usually with electric current applied to remove oxides, and plated with tin. It is then passed through a melting tower to melt and reflow the tin coating to form the shiny tin surface and the tin-iron alloy layer, chemically treated to stabilize the surface to prevent growth of tin oxide, and lubricated with a thin layer of synthetic oil. 

Block B shows the electrolytic copper recovery cell, which recovers metallic copper and regenerates sulfuric acid from the metal salts in the hot sulfuric acid pickle solution. It was originally felt that trace metals (zinc, tin, lead) would interfere with the recovery of pure copper. By controlling current density at 50 to 100 A/m 1 2 3, however, pure copper can be recovered while maintaining the copper concentration in the pickle bath at 15 g/L. 

The secondary pickle reservoir is also shown in Block B. Copper sulfate accumulates in this bath and eventually crystallizes out. These crystals can be recovered and sold as a copper-rich sludge or added to the electrolytic copper recovery loop. 

The two water desalination applications described above represent the majority of the market for electrodialysis separation systems. A small application exists in softening water, and recently a market has grown in the food industry to desalt whey and to remove tannic acid from wine and citric acid from fruit juice. A number of other applications exist in wastewater treatment, particularly regeneration of waste acids used in metal pickling operations and removal of heavy metals from electroplating rinse waters [11]. These applications rely on the ability of electrodialysis membranes to separate electrolytes from nonelectrolytes and to separate multivalent from univalent ions. 

Large quantities of this acid are used in the metallurgical industries in the pickling of iron and steel, in the production of zinc, in the electrolytic refining of copper and other metals, in electroplating operations, and so forth. 

Finally, impurities that accumulate during usage of electrolyte can also be recovered. For example, Ni-Cu-Zn ferrite powder can be prepared from steel pickled liquor and electroplating waste solutions by a hydrothermal process [112],... 

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