3D Printing of Hydrogel Filters Containing Algae Cells for Copper Removal from Contaminated Water

Copper contamination of drinking water and marine areas is detrimental to human health and the environment. Physical and chemical approaches currently used for copper removal from water tend to be expensive and may introduce chemicals to the water. Using suspended algae to remove copper is a biological approach. Its cost is relatively low, and algae can be used for other purposes after being used for copper removal. However, this approach using algae is currently limited in its usefulness due to technological barriers. For example, chemical agents used to remove suspended algae from water after copper is absorbed, can cause secondary contamination. Using immobilized algae instead of suspended algae can overcome these problems. In this preliminary study, hydrogel filters containing algae cells and those containing no algae cells are printed on an extrusion-based 3D printer. They were used in a custom-build filtration setup for copper removal. Experimental results show that hydrogel filters containing algae cells reduced copper concentration in the test solution by about 83% (from 3 to 0.5 ppm) after one hour of filtration, while hydrogel filters containing no algae cells reduced copper concentration in the test solution by about 50% (from 3 to 1.5 ppm) after one hour of filtration.