Potential of carica papaya seed-derived bio-coagulant to remove turbidity from polluted water assessed through experimental and modeling-based study

It is important to develop renewable bio-coagulants to treat turbid water and efficient use of these bio-coagulants requires process optimization to achieve robustness. This study was conducted to optimize the coagulation process using bio-coagulant of deshelled Carica papaya seeds by employing response surface methodology (RSM). This bio-coagulant was extracted by a chemical-free solvent. The experiments were conducted using the Central Composite Design (CCD). Initially, the functional groups and protein content of the bio-coagulant were analyzed. The Fourier Transform Infrared Spectroscopy analysis showed that the bio-coagulant contained OH, C=O and C-O functional groups, which enabled the protein to become polyelectrolyte. The highest efficiency of the bio-coagulant was obtained at dosage of 196 mg/L, pH 4.0 and initial turbidity of 500 NTU. At the optimum conditions, the bio-coagulant achieved 88% turbidity removal with a corresponding 83% coagulation activity. These findings suggested that the deshelled Carica papaya seeds have potential as a promising bio-coagulant in treating the polluted water

Deshelled carica papaya seeds as natural coagulant for improvement quality of river water

This study evaluated the efficiency of deshelled papaya seeds as the natural coagulant in improving quality of river water. The deshelled papaya seeds biomass was mainly characterized for functional groups using FTIR, surface charge and protein content. Coagulation and flocculation tests were conducted using batch test for various dosages and pH values. The optimum dosage and pH were then tested in treating river of Class III to Class V. The functional groups in deshelled papaya seeds were O-H, C=O and C-O groups. The surface charge and protein content was +0.4 meq/g and 363 mg/g, respectively. The deshelled papaya seeds coagulant was able to remove turbidity up to 87.6 and 88.3% for river of Class III and Class IV, respectively, as well as 57.6 and 62.1% of total coliform and escherichia coli, respectively, from Class III river at dosage 196 mg/L and pH 4. This study demonstrated that the deshelled Carica papaya seeds-derived coagulant is capable in treating common pollutants of river and simultaneously shows antibacterial properties

Recent advances on coagulation-based treatment of wastewater: transition from chemical to natural coagulant

Purpose of Review: The use of conventional chemical coagulant in treatment of wastewater is gaining great attention. Drawbacks related to the prolonged effects on human health and environment due to the generation of by-product non-biodegradable sludge are becoming the latest topics. Transition from chemical to natural coagulant can be a good strategy to reduce the aforementioned drawbacks. Therefore, this review aims to provide critical discussions on the use of natural coagulant along with the comparative evaluation over the chemical coagulant. Recent Findings: Treatment performances by chemical and natural coagulant have been reviewed on various types of wastewater with different success rates. Based on this review, a transition from the use of chemical to natural coagulant is highly suggested as the performance of the natural coagulant is comparable to that of the chemical coagulant and in some cases even better. The comparative advantages and disadvantages also convinced that the natural coagulant stands a great chance to be used as an alternative over the chemical coagulant. Summary: Though the current utilization of natural coagulant is encouraging, three main aspects were overlooked by researchers: active coagulant agent, extraction, and optimization due to different wastewater characteristics. Furthermore, delving into these aspects could clarify the uncertainties on the natural coagulant. Hence, it makes this transition a prospect of green technology with sustainable application towards wastewater treatment