Electrolyte, cooling

Thermal drift. It is essential that the STM can acquire images rapidly (i.e. 10 seconds) since thermal drifts due to electrolyte cooling, expanding electrodes, etc. will degrade lateral resolution over longer collection times. 

May 1978 Sump, catch basin under zinc electrolyte cooling tower. 

A form of corrosion resulting from presence of two dissimilar metals (such as steel and copper) in an electrolyte (cooling water), whereby the less noble anodic metal (steel) corrodes. 

Equipment for ECF, including a bipolar electrolyzer, a gas trap, an apparatus for condensation of hydrogen fluoride from electrolysis gases, and an electrolyte cooling system, are described elsewhere (94USP5322597, 95RUP2026889). 

The current requirements for the surface treatment of HM fiber are relatively high and there is an appreciable heating effect, which necessitates cooling of the electrolyte in order to control the rate of treatment. Also, with some electrolytes, cooling is essential to avoid thermal decomposition. 

Fig. 2.23 Simplified heat balance over dectioc micil reactors, (a) Simple batch reactor with electrolyte cooling via an interna) heat eitchanger. (b) Fbw-difoiaih reactor with the electrolyte acting as a h -eiEchiiigjsg medium.

Electrolysis cell. This is shown in Fig. VI, 31, 1 and is almost self-explanatory. The cylindrical cell of Pyrex glass (6" long by 2 " diameter) is cooled by immersion in a cooling bath. The electrodes consist of two platinum plates (4 cm. X 2-5 cm. X 0-3 mm.), which are placed about 2 mm. apart. The temperature of the electrolyte is maintained at 30-35° by means of the internal cooling coil and also by immersion of the cell in ice-water. A current of 1 5-2 0 amperes is passed until the electrolyte becomes slightly alkaline, which normally takes about 20-50 per cent, longer than the calculated time on the basis of the current and the amounts of acid employed. It is advantageous to reverse the direction of the current occasionally. 

The matte can be treated in different ways, depending on the copper content and on the desired product. In some cases, the copper content of the Bessemer matte is low enough to allow the material to be cast directly into sulfide anodes for electrolytic refining. Usually it is necessary first to separate the nickel and copper sulfides. The copper—nickel matte is cooled slowly for ca 4 d to faciUtate grain growth of mineral crystals of copper sulfide, nickel—sulfide, and a nickel—copper alloy. This matte is pulverized, the nickel and copper sulfides isolated by flotation, and the alloy extracted magnetically and refined electrolyticaHy. The nickel sulfide is cast into anodes for electrolysis or, more commonly, is roasted to nickel oxide and further reduced to metal for refining by electrolysis or by the carbonyl method. Alternatively, the nickel sulfide may be roasted to provide a nickel oxide sinter that is suitable for direct use by the steel industry. 

In the atomizing process, a stream of molten zinc is broken into tiny droplets by the force of a pressurized fluid impinging on the stream. The fluid can be any convenient material, although air is normally used. The atomized drops cool and soHdify rapidly in a coUection chamber. The powder is screened to specified sizes. Particulate zinc is also produced by other methods such as electrolytic deposition and spinning-cup techniques, but these are not of commercial importance. 

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