In this master thesis, magnesium salt slags were dissolved in a two-step leaching process in order to generate different salts from the solutions. The potential for a further use of the salts was evaluated with specific analyses. The leaching process consists of a neutral leaching step with water as well as an acidic step, where a mineral acid is applied. Because this method was originally developed and tested using hydrochloric acid, the main focus of this thesis rested upon tests regarding the qualification of other mineral acids as leaching agents. A fundamental characterisation of two different magnesium salt slags enabled the design of an appropriate leaching process and in consequence to attain a variety of salt products. After analysing the chemical composition, it should be acknowledged that due to the high concentration of impurities in the salts generated by the acidic leaching, the possibility of using them in the common fields of application do not seem probable. Nevertheless, it can be stated that the amount of waste requiring disposal can be reduced to four percent of the original. This exhibits considerable significance, owing the fact that magnesium salt slag is regarded as an environmental hazard.