Effective removal of Pb2+ from oral medical wastewater via an activated three-dimensional framework carbon (3D AFC)

Abstract

Oral medical wastewater with heavy metal ions (such as plumbum, Pb2+) is regarded as the main pollutant produced in the oral cavity diagnosis, and the treatment process can pose a serious threat to human health. The removal of Pb2+ from oral medical wastewater facing major difficulties and challenges. Therefore, it is of great significance to take effective measures to remove Pb2+ by using effective methods. A new activated three-dimensional framework carbon (3D AFC), regarded as the main material to remove Pb2+ in the oral medical wastewater, has been fabricated successfully. In this experiment, the effects of 3D AFC absorbing Pb2+ under different conditions (including solid-to-liquid ratio, pH, ionic strength, contact time, and initial concentration, etc.) were discussed. And the result revealed that the adsorption kinetics process of Pb2+ on 3D AFC conformed to the pseudo-second-order model and the adsorption isotherm conformed to the Freundlich model. Under the condition that pH = 5.5 and T = 298 k, the calculated maximum adsorption capacity of 3D AFC for Pb2+ was 270.88 mg/g. In practical application, it has strong adsorption ability for Pb2+ in oral medical wastewater. Thus, 3D AFC shows promise for Pb2+ remove and recovery applications because of high adsorption capacity for Pb2+ in oral medical wastewater due to its high specific surface area, outstanding three-dimensional network structure.

N‐Doped Porous Carbon with Outstanding Pb2+ Adsorption Capacity in Wastewater

“…3c shows that, when the pH ranged from 1.3 to 9.3, the adsorption behavior of Pb 2+ on the NPC surface did not correlate with the ionic strength (0.001–0.005 mol L −1 ), and this result can be explained by the fact that the ionic valence state of Na + is lower than that of Pb 2+ 32. This result was consistent with formerly reported results 6, 33. It could also be inferred that the adsorption mechanism of Pb 2+ on the NPC surface was by inner surface coordination 34.…”

“…Pb 2+ is one of the primary heavy-metal contaminants. Jin et al [5] measured the leaching concentration of Pb 2+ in fly ash above 0.02 mg L -1 , and Song et al [6] found a Pb 2+ concentration in medical wastewater of 0.00835 mg L -1 . However, the World Health Organization (WHO) stipulates that the content of Pb 2+ in wastewater should be controlled below 0.01 mg L -1 [7].…”