The role of Procambarus clarkii in achieving Sustainable Development Goal-6

Abstract

Pollution's cumulative negative repercussions are a key interconnected component of many worldwide challenges (as, incidence of diseases, malnutrition, poverty, etc.) that can make achieving sustainability difficult. Consequently, the current research aims, for the first time, to throw the light on the possibility of investment of Procambarus clarkii exoskeleton waste, not only in reducing metal pollution but also in paving the way for tackling some of these challenges. The study was divided into two parts; (1) conducting experiments in batches to determine the optimal operating parameters (contact duration ―minutes‖, pH, and initial metal concentration ―mg/L‖) required to reduce copper (Cu2+) or zinc (Zn2+) ion concentrations in aqueous solutions using 0.5 g Chitosan (CS) extracted from P. clarkii (to meet the values set by WHO and Egyptian Governmental Law No. 48, 1982); and (2) elucidating the synergistic relationship between achieving SDG6.3.1 with other SDGs. Our results showed that the adsorption process, for both ions on CS, attained equilibrium at 20 minutes, pH 5.0 (for Cu2+) and 7.0 (for Zn2+), and initial concentrations of 4.49 mg/L (for Cu2+) and 5.15 mg/L (for Zn2+). The removal efficiency of the metal ions by CS decreased in the order of Cu2 (99.11%) followed by Zn2+ (88.35%). Moreover, the investigated dose of CS (0.5 g) proved its potential to meet both the Egyptian and WHO guideline values for the optimal concentrations of Cu2+ and Zn2+ ions within the 15-minute period. The very fast adsorption kinetics (20 min) observed for the studied metals showed an advantage for using CS in the purification system for the industrial sector. As a result, the percentage of untreated industrial wastewater will decrease, clearing the path for Egypt to make significant progress toward achieving SDG-12.4, SDG2.1, SDG-3.3, SDG-11.5, SDG-6.4, SDG-1.5, SDG-11.6, and SDG-13.1 by 2030.