Utilization of carica papaya seeds as natural coagulants for turbidity removal from wastewater

Abstract

In this research, turbidity was eliminated using the natural coagulant Carica papaya. Using wastewater from an industrial park in Mazandaran, Iran, and a salt solution of NaCl, this investigation sought to improve the coagulant efficiency. The greatest amount of turbidity clearance was determined by examining the effects of pH and coagulant dosage. After 30 minutes of treatment, the use of Carica papayaseeds at the recommended dosage of 200 mg/L resulted in the greatest turbidity reduction effectiveness of 89%. Under ideal circumstances, alum concentrations of 100 mg/L and Carica papaya seeds concentrations of 100 mg/L after 30 minutes of treatment, dual flocculation of Carica papaya seeds and alum had a synergistic effect, resulting in a maximum turbidity reduction of 95%. Utilizing response surface methodology (RSM) based on a central composite design (CCD), the coagulation-flocculation (CF) process was improved. On the elimination of turbidity, the impacts of three parameters, contact time, pH, and natural coagulant dosage were assessed. The flocculation process was clarified by the use of scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) investigations. The findings showed that the active components of Carica papaya seeds, such as proteins, polysaccharides, and fiber, contribute to their capacity to coagulate turbidity.