Comparison of Four Plant-Based Bio-Coagulants Performances against Alum and Ferric Chloride in the Turbidity Improvement of Bentonite Synthetic Water

Abstract

Due to their cost-effectiveness, low toxicity, and naturally renewable properties, bio-coagulants for water treatment are gaining popularity. In this context, four bio-coagulants were tested for their ability in turbidity reduction in a synthetic bentonite suspension: Opuntia ficus indica (OFI) and Moringa oleifera (MO) seeds, two well-established vegetal materials in the domain of bio-coagulation, and Algerian Aloe vera (AV) and Pinus halepensis seeds (PHS), both of which have received very few or no study in turbidity reduction in water and wastewater. A comparative study was conducted with regard to two well-known inorganic coagulants, ferric chloride and Alum. Extraction salts, pH, coagulant dose, initial turbidity, and aging effects were examined. When compared to chemical coagulants, the four bio-coagulants worked very well, removing approximately 100% of the turbidity at natural pH of 7.5 using optimal doses of 1.5, 3, 3, 3.5, 1.5, and 1.5 mL/200 mL for AV, OFI, MO, PHS, Alum, and FeCl3, respectively, at a broad range of pH (2 to 8), and causing no pH alteration of the treated water. Polysaccharides and proteins involved in inter-particle bridging and charge neutralization may be the active coagulation-flocculation molecules. The four bio-coagulants produced less sludge amount than Alum and Ferric chloride. This research not only shows that MO and OFI are effective in eliminating turbidity, but it also highlights the great potential of Algerian AV and PHS seeds as promising bio-coagulants in the treatment of polluted water.

Utilization of aloe vera as a biocoagulant for turbidity, total dissolved solid (TDS), and iron (Fe) removal in well water

“…As shown in Figure . 6 3, the addition of LB-HCl coagulant to well water resulted in a significant decrease in turbidity values [13]. HCl solution also plays a role in increasing polygalacturonic acid levels and protein levels extracted in Aloe vera, thereby increasing the efficiency of Aloe vera as a coagulant [14]. In this study, it was found that the turbidity removal efficiency decreased in line with the increase in coagulant dose.…”

Parametrical Study for the Effective Removal of Mordant Black 11 from Synthetic Solutions: Moringa oleifera Seeds’ Extracts Versus Alum

“…Due to their biodegradability and environmental friendliness, the use of natural coagulants in water treatment has become essential. In recent years, there have been numerous reports of natural coagulants derived from diverse plant species, including Jatropha curcas [15], banana peels [16], bagasse [17], Aleppo pine seeds, prickly pear and Aloe vera mucilage [18]. In accordance with these results, natural coagulants have a high prospect of replacing the traditional chemical coagulant, since they demonstrate promising treatment performance.…”

“…The obtained powder is referred to as MOP. A saline extraction was performed according the method described earlier [18]; the resulting mixture is referred to as MOPS. An aqueous extraction was also undertaken for comparison purposes (MOPW).…”

Natural Organic Matter Removal in Surface Water Treatment via Coagulation—Current Issues, Potential Solutions, and New Findings

“…Although coagulation has been applied as the main surface water treatment process in DWTPs across the world for decades, there are still a number of issues that researchers investigate. They include the application of ecologically friendly biocoagulants, the development of novel hybrid coagulants, and the possibility of increasing the efficiency of surface water purification by combining coagulation with different unit water treatment processes [5,[7][8][9]. Such research is necessary not only for the purpose of overcoming known limitations and disadvantages of conventional coagulation, but also to ensure its continuous applicability in the context of rising challenges [7].…”

“…The most pressing problems associated with water treatment via coagulation appear to be the vulnerability of the process to changing NOM concentration and composition, and the consequences of employing metallic salts as coagulants [7,10,11]. Revisiting the topic of surface water purification via coagulation with consideration of both the current and anticipated challenges is necessary.…”