Enhanced removal of arsenic and chromium contaminants from drinking water by electrodeposition technique using graphene composites

This work reports the use of compacted graphene composites for the removal of As and Cr heavy metal ions from contaminated water by electrodeposition. The removal of the metal ions contaminants was studied by using two different positions of electrodes: on the top and on the bottom of the composite. The highest removal percentages of As and Cr (≈70%) were reached when the electrodes are located on the bottom of the composites. A maximum removal capacity of 38 mg/g and 32 mg/g was obtained for As and Cr ions (after 24 h), respectively. The As and Cr ions were also removed in presence of drinking water and found an increase in the removal percentage from 70% to 87% for As and from 70% to 98% for Cr, which indicates that the additional ions in the drinking water favored the performance of the graphene composites for the removal of contaminants. The solid graphene composites facilitate the removal of the adsorbed contaminants into contaminated water in comparison with the reported composite powders. Hence, the proposed methodology of this work could be an alternative for the removal of heavy metal ions from contaminated water effluents in mines or water treatment plants.