Desferrioxamine B (DFOB) assisted nanofiltration system for the recycling of gallium from low concentrated wastewater

Gallium is classified as a technology metal as it is important for technological innovations. It is also referred to as a strategic metal, which emphasizes its economic relevance. In addition, gallium is a critical raw material that is strategically important but only available in limited quantities. However, recycling dissolved gallium from low-concentration wastewater is often not done due to the lack of suitable technologies. This research presents a membrane-based approach using the siderophore Desferrioxamine B for the recycling of gallium. Nanofiltration membranes were used to separate gallium from other metal impurities (such as arsenic). The membranes recovered about 70 % of gallium from low-concentrated synthetic wastewater. Afterward, the membranes were tested using industrial wastewater, and a similar recovery rate was observed. A model was developed to predict operation parameters that would lead to the highest recovery rate of gallium with the minimum impurities. The model showed that recycling more than 90 % of gallium from wastewater is possible using this approach. Therefore, the siderophore-assisted nanofiltration approach demonstrated in this research showed great potential for the sustainable recycling of gallium from industrial wastewater.