Optimization of biogenic sulfuric acid production for bioleaching applications in the waste management sector
Abstract
Availability of resources is an important factor for countries like Austria. Huge amounts of secondary resources are incorporated in different anthropogenic stocks like end of life vehicles, waste electric and electronic equipment and ashes and slags from metallurgical industries and waste incineration facilities. Therefore, the recovery and recycling of valuable metal resources from this waste streams is favourable. An innovative approach for metal recovery is the use of biologically produced sulfuric acid. Using bioleaching requires the maintenance of a relatively low pH-value, which makes it necessary to externally add sulfuric acid for pH-regulation. Therefore, the overall goal of the OPTIMO project is to biologically produce a 1.5 – 2 molar biogenic sulfuric acid by using sulfur-oxidizing bacteria. The generated acid will afterwards be applied in the pH-regulation of heap-bioleaching system in which different waste substrates such as waste electronic equipment will be treated. Furthermore, spent medium bioleaching will be used to treat other metal containing waste substrates. To recover the dissolved metals from the lixiviant, a bio electrochemical system will be optimized to recover Zink with an efficiency of up to 90%. Selective precipitation will be another method investigated for the recovery of Zinc. To reach the desired project goals, different mesophilic and thermophilic, sulfur-oxidizing bacteria will be compared by BOKU and K1-MET according their acidity production rate and cultivated in 1 L stirred tank reactor systems. Partner MU will be responsible for the molecular biological monitoring of the conducted experiments. For the bio electrochemical Zinc recovery, K1-MET will built up an H-Cell followed by an optimization of the cathode. The results of the project should show a potential new way for resource recovery and recycling from secondary resources and will help to optimize the circularity of metals.
keywords biogenic sulfuric acid sulfur-oxidizing bacteria metal recovery bioelectrochemistry
Publikationen
Project staff
Klemens Kremser
Dipl.-Ing. Dr. Klemens Kremser
klemens.kremser@boku.ac.at
Tel: +43 1 47654-97498
Project Leader
01.01.2022 - 31.12.2022
BOKU partners
External partners
Masaryk University
none
partner
K1-MET GmbH
none
coordinator