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Anion exchange separations have been devised to purify model solutions of the usual pickling liquor (SPL) obtained from hot dip galvanization to produce a suitable ZnCl2 electrolyte for electrodepositing pure Zn. The method was based on the established anion-exchange distribution functions in chloride media. Both the simple batch and the more accurate chromatographic methods of separation were examined. The loaded solutions contained Zn, Fe, Mn, Ni and Pb of different concentrations with 1.8 - 2 M NaCl or HCl as the background. The resin bed primarily retained Zn while divalent Fe, Mn and Ni were removed in the loading and the continued rinsing steps with the mobile phase at the initial level of Cl- ion concentration. The elution of Zn was carried out by a significantly reduced Cl- ion concentration. The preliminary reduction of the iron to its divalent state was found of utmost importance. The only difficulty arises from the separation of Pb, which has an equilibrium distribution function comparable to the anion exchange of Zn, however in Europe this minor impurity should not be present at disturbing levels. Kinetic examination of the batch process revealed that Zn sorption is virtually complete within 20 minutes, however despite the low distribution coefficients, some 10 % of iron is also sorbed. Almost 90 % of the retained iron could be in the Fe(III) state caused by aerial oxidation. It was also found that the elution of Zn in the batch technique was not possible by just lowering the Cl- ion concentration. Therefore, the chromatographic method is the only possible way if only chloride media are to be applied.

The salt content in the secondary dross obtained beside the recovered aluminium by the hot processing of the primary melting dross hinders further utilization of this material. Secondary dross samples obtained from the industrial hot processing of the primary dross generated by the melting of aluminium alloy scrap were leached with water at room temperature with different Liquid/Solid (L:S) ratios. Vessel filling (the relative volume occupied by the sludge) in the shaking bottles required further consideration in the interpretation of the results. Samples taken regularly within 15 minutes during vigorous shaking showed that NaCl and KCl can be dissolved almost instantly, and completely irrespective of the parameter settings. However, the fluoride additive (CaF2) has a complex behaviour. The results suggest its relation to some side reactions indicating also the conditions of the hot process producing the examined material. The results suggest that the salt content of the secondary aluminium dross can be lixiviated within a 2 -4 minutes virtually completely, but the L:S ratio and the a vessel filling have to be coordinated. At the lowest L:S ratio examined of 1.0, a vessel filling of max. 11% should be observed to achieve this fast salt dissolution. The same dissolution rate can be reached with double the vessel filling (i.e. smaller unit) if the L:S is also increased in this ratio.

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Abstract.Tube boiler has an important function to change water from liquid to vapor phase. However, it needs a material selection which has a role to find the best material properties, mainly at steam power plant. One of the properties is to receive a pressure when a boiler is being operated. Several literatures suggested that material characteristics affected the life of a material after receiving pressure repeatedly which lead to failure. The aim of this study is to find the best formula in anticipating the occurrence of repeated failures of a tube based on pressure aspect, mainly in steam power plant. Results show that Analysis of various papers mentions failure caused by several interrelated factors. Factors that causes a failure was discussed due to corrosion and overheating, while the pressure factor is not a main factor causing a failure. The best formula for determining the failure analysis in terms of stress are material selection, visual observation of the failure form, knowing the location of the failure, measuring the thickness and using the Von Mises and API calculations to determine pressure acceptable to the material. This study suggests to use these findings as a pressure maximum which can be accepted material. In further studies related to find the remaining life of the material in terms of stress and thickness on tube boiler operation.