Low Coagulant Dose Research Articles

Arsenic Treatment Using Electrolytic Ferrous Reagent to Replace Bulk Ferric Chloride

Key TakeawaysAs federal maximum contaminant level (MCL) recommendations for arsenic in drinking water are being reviewed, US utilities are preparing for more stringent regulations.If faced with reducing its treated water's arsenic concentration to 5 μg/L, the City of Alamosa, Colo., would need to increase its ferric chloride dose—raising supply, cost, and operational concerns.To avoid these issues, the city explored a new technology that generates a ferrous reagent via an in situ electrolytic process to replace bulk ferric chloride.The electrolytic ferrous reagent removed arsenic to below 5 μg/L, reduced permeate manganese levels, and improved effluent quality with a far lower coagulant dose.

Vanadium removal and floc characteristics of tannin biocoagulants and iron sulphate in the treatment of mine effluent

This study compared the performance of tannin (quebracho and spruce) and iron sulphate (FS) coagulants for the removal of vanadium from effluent derived from an abandoned vanadium mine. The efficacy of the materials was studied at the natural pH of the mine effluent (7.4), and at adjusted pH levels of 4 and 9. The quebracho tannin coagulant (QT) recorded impressive turbidity and vanadium removals of above 88% over a wide pH range. However, the spruce tannin coagulant (ST) was not as effective at pH 9 (39%) although it showed an improved vanadium removal of 46% and 70% at pH 7.4 and 4, respectively. This was attributed to the lower charge density of ST than that of QT, and to a loss of cationic properties at pH 9. FS performed better in terms of vanadium removal (pH 4: 86%, pH 7: 98%, pH 9: 100%) with lower coagulant doses, although effective turbidity removal required precise pH control. QT produced the largest flocs and the highest floc regrowth at pH 4 and 7. Under alkaline conditions, tannin coagulants exhibit no regrowth, which implies that a careful flocculation and floc separation step is needed. The natural organic matter fractionation results revealed that FS effectively removed hydrophilic carbon (76%) in a pH-controlled mine effluent better than tannin coagulants (QT: 12% and ST: 22%) from the pH 4 effluent; however, ST removed hydrophobic carbon entirely. All coagulants adequately removed humic substances, with FS being the most efficient (88%), followed by ST (53%) and QT (47%). X-ray photoelectron spectroscopy (XPS) analysis of jar test residues showed that some of the vanadium removed existed in the V(IV) oxidation state.

Preparation and Coagulation Performance of Polyaluminum Lanthanum Silicate Coagulant

In order to address the growing problem of water pollution caused by the excessive discharge of contaminants and provide a better aquatic ecosystem for the public, increasing attention has been paid to the harmlessness and efficiency of coagulation. In this study, polyaluminum lanthanum silicate (PALS) was synthesized through co-polymerization as a novel coagulant to treat wastewater. FTIR, XRD, and SEM were used to analyze the morphology and structure of the material, which further confirmed that the PALS was successfully synthesized. The results indicated that PALS had a great performance in the treatment of a kaolin-humic acid suspension under the optimal synthesis conditions with Al/Si = 3, La/Si = 0.1, and basicity = 0.7. Compared with conventional coagulants, PALS exhibited a better performance at a low coagulant dose and could achieve a good removal effect for an ultraviolet wavelength less than 254 nm (UV254) (83.87%), residual turbidity (0.49 NTU), and dissolved organic carbon (DOC) (69.57%) at the optimal conditions. Additionally, the PALS showed a better effect on phosphate removal than other coagulants did, where the removal efficiency could reach 99.60%. Charge neutralization and adsorption bridging were the potential wastewater treatment mechanisms employed by the PALS, which showed varied contributions under different pH levels. The results indicated that PALS can be a promising coagulant in water treatment.

Modified coagulation processes using polyferric chloride and polytitanium tetrachloride for the removal of anionic dye from aqueous solution

Synthetic dyes are one of the most important contaminants in textile wastewater, which are often toxic and carcinogenic. This study aimed to determine the efficiency of coagulation and flocculation process using polyferric chloride (PFC) and polytitanium tetrachloride (PTC) in removing Reactive Blue 19 (RB19) anionic dye from aqueous solution. This laboratory-scale study examined coagulant preparation, the effect of pH (3–11), concentration of PFC and PTC coagulants (100–500 mg/L), and initial dye concentration (70–250 mg/L). The results showed that the dye removal efficiency of PFC was 92.37% at an optimum pH of 9, an optimal dose of 350 mg/L, and dye concentration of 150 mg/L. The dye removal efficiency of PTC was 99.83% at an optimum pH of 7, optimal dose of 350 mg/L, and dye concentration of 200 mg/L. The correlation coefficient between coagulant dose (r = 0.91, p = 0.001) and initial dye concentration (r = 0.83, p = 0.01) was significant with dye removal efficiency for PTC. Based on the results, it can be concluded that the PTC with higher removal efficiency, lower coagulant dose, lower effects on solution pH, and higher density of settled sludge has better efficiency to remove RR19 dye from colored wastewater compared to PFC.

Impact of low coagulant dosages on protein fouling of ultrafiltration membranes

Biopolymers have been identified as the primary source of fouling for ultrafiltration (UF) membranes, however the relative contribution of its components (e.g., proteins and polysaccharides) to fouling are still unclear. Previous natural water studies have shown that applying low doses of coagulant (< 1 mg metal/L) significantly reduces membrane fouling. The impact of inline coagulation on UF fouling for three different model protein solutions was examined at bench-scale. Results show that when compared to no coagulant addition, a low coagulant dose (2 μM Al or 0.3 mg/L alum) is capable of significantly reducing membrane fouling when considering feed solutions containing bovine serum albumin (BSA) and ovalbumin (OVA). Conversely, the same alum dose resulted in the most fouling when considering β-lactoglobulin (BLG). Protein rejection was also correlated with irreversible fouling resistance, suggesting fouling mitigation was due to weakened protein-membrane interactions instead of a more reversible fouling layer. Fouling trends for BSA and OVA were similar to those in previous studies with natural surface waters, which suggest that proteins are major contributors to UF fouling which may be mitigated with low dosages of coagulant. It is hypothesized that at low alum doses, the surface hydrophobicity of the protein and the fouling layer is altered, leading to weaker interactions and thereby reducing fouling.

Coagulant dose as an operating parameter in a solid contact clarifier

Abstract The objective of this study was to determine the applicability of the laboratory flocculation test (Jar Test) for a solid contact clarifier. Cohesivity, a parameter characterizing the sludge blanket can be established by determining the Sludge Cohesion Coefficient (SCC) by conducting a Sludge Cohesion Test (SCT). A series of laboratory tests were performed using the Jar Test and SCT. Considering the large number of variable parameters involved with natural raw water, sludge samples were prepared using synthetic raw water with varying turbidity and coagulant dose combinations. A comparison was made between the optimum coagulant dose obtained using the two tests. Highest SCC observed at the optimum coagulant dose was within the range of 0.6–3.3 m/hr. Low SCC values indicate a light and fragile sludge blanket whereas high SCC values indicate a quick settling consistent blanket. With increasing raw water turbidity, the optimum coagulant dose given by SCT is lower than that of the Jar Test. Hence, at higher raw water turbidity occurrences, it may be possible to operate the upward flow solid contact clarifiers with lower coagulant dose. A significant quadratic relationship is observed between the optimum coagulation doses with R2 = 0.9 and α &amp;lt; 0.05.

Decolorization of reactive dye Remazol Brilliant Blue R by zirconium oxychloride as a novel coagulant: optimization through response surface methodology.

The aim of the present study was to investigate the performance of a novel coagulant, i.e. ZrOCl2, for the removal of anthraquinone-based reactive dye from aqueous solution. An ideal experimental setup was designed based on central composite design using response surface methodology to determine the individual and interactive effects of different operational variables (i.e. pH, coagulant dose and dye concentration) on treatment performance in terms of dye and chemical oxygen demand (COD) removal efficiencies. Total 92.58% dye and 85.33% COD removal were experimentally attained at optimized conditions at low coagulant dose, i.e. 156.67 mg/L for the dye concentration of 105.67 mg/L at pH 2. To validate the working pH of the metal coagulant, the static charge of ZrOCl2 was measured using Eh value. The performance of the coagulant was validated with experimental and predicted values in the selected data set, and R2 values for both responses were found to be 0.99 and 0.95 respectively, which shows the reliability of the experimental design. Further, the toxicity of the coagulant was assessed and no such toxicity was found even up to the concentration of 500 mg/L, proclaiming the disposal of sludge may not exhibit any threat to humans. Experimental results suggested that the ZrOCl2 could be used as an eco-friendly coagulant for dye wastewater treatment.

Characterization of UF foulants and fouling mechanisms when applying low in-line coagulant pre-treatment

Fluorescence spectroscopy was used as a characterization method to examine organic fouling of single ultrafiltration (UF) fibres at bench-scale. Low doses of coagulant were applied to modify organic properties, without significant formation of precipitates. This approach compliments previous studies investigating coagulation as a pre-treatment method for UF fouling control, which have principally focused on reduction of foulant concentrations. Using a continuous system, short time-scale fluorescence results demonstrated significant adsorption of humic components to virgin membrane fibres. Following an initial adsorption phase, protein-like material was the only organic component to be significantly removed by UF. Low doses of coagulant (<1 mg/L as alum; < 0.043 mg/L as Al3+) were observed to significantly reduce irreversible fouling rates for two different surface waters. Paralleling reduced irreversible fouling, surface tryptophan fluorescence resulting from material adsorbed to the fouled membrane increased, as measured using a fibre optic probe. Analysis of peak shifts in the protein-like component revealed a red-shift at low coagulant dose, possibly indicative of greater exposure of tryptophan residues resulting from conformational changes in the protein structure. It is hypothesized that low coagulant doses modified membrane-foulant interactions, resulting in increased adsorption of protein-like matter to the surface. Subsequent interactions of bulk foulants with the adsorbed organic monolayer discouraged further adsorption and reduced irreversible fouling potential.

An application of cellular organic matter to coagulation of cyanobacterial cells (Merismopedia tenuissima)

Algae affect the performance of drinking water treatment significantly when they decay and release considerable amounts of cellular organic matter (COM). The study describes the cyanobacterium Merismopedia tenuissima and its COM and investigates the effect of their simultaneous coagulation. As COM is highly complex mixture, we characterised it in terms of hydrophobicity, protein content and molecular weights (MWs). To describe the coagulation mechanisms and molecular interactions in the system, we determined both COM and cell surface charge by means of potentiometric titration and zeta potential analysis, respectively, and performed the jar tests with single components and their mixtures with and without a coagulant (ferric sulphate).The coagulation tests performed with the individual components or with their mixtures proved efficient cell removals (up to 99%) but relatively low COM removals (37 ÷ 57%). This disproportion can be attributed to the prevalence of hydrophilic compounds and to the high portion of low-MW organics in COM. Coagulation of COM/cell mixtures achieved comparable efficacy with single component tests, using even lower coagulant doses. Furthermore, COM presence substantially deviated the pH optimum for cell removal and thus altered coagulation mechanisms. While single cells interacted prevailingly through adsorption onto Fe-oxide-hydroxides at about neutral pH (6.0–7.7), the COM/cell mixtures succumbed to charge neutralisation by Fe-hydroxopolymers within moderately acidic pH range (5.0–6.5). Moreover, COM initiated cell flocculation also at acidic pH in both the presence (pH 3.4–3.9) and the absence of a coagulant (pH 3.6–4.6). This supportive effect is ascribed to relatively high-MW COM (>10 kDa), serving as a natural flocculant through inter-particle bridging mechanism and exhibiting nearly the same COM/cell removals as ferric sulphate.

Removal of Oocystis algae from freshwater by means of tannin-based coagulant

The tannin-based coagulant agent Acquapol C1 was tested for algae removal. This coagulant can be used in drinking water treatment and consists of a chemically modified tannin extract from Acacia mearnsii. Low coagulant doses reached high algae removal percentage, and operational conditions of neutral pH and room temperature allow up 80 % algae removal with 5 mg L−1 of coagulant. If compared with other natural or inorganic coagulants, Acquapol C1 is more efficient than aluminum sulfate, a classical metal salt for water clarification. Experiments also were carried out in a pilot plant installation which gives a similar efficiency as the discontinuous jar-test experiments for algae removal.

Coagulation strategies to decrease fouling and increase critical flux and contaminant removal in microfiltration of laundry wastewater

The principal objectives were to identify optimal treatment of laundry wastewater using coagulation and microfiltration (MF) so as to decrease fouling, increase critical flux, and increase contaminant removals. Experiments were designed to simulate operation of the Army’s shower water reuse system (SWRS) which operates using constant-flux MF membranes with 0.22μm pores. The SWRS is a transportable wastewater treatment system that is used in remote locations. Critical flux was measured using quick step-flux tests and also using multi-cycle tests with the objective of identifying rapid methods for evaluating design and operation of coagulation/MF systems. Low molecular weight quaternary amine polymers were effective coagulants that resulted in low coagulant doses, low chemical volume, and good coagulation/MF using a range of doses. Charge-neutralization (CN) and under-dosing (UD) at 40% of CN improved contaminant removals, decreased fouling, and increased critical flux from 45Lm−2h−1 (LMH) for raw wastewater to a maximum 450LMH using CN. The increased critical flux and good results over a wide range of coagulant doses can result in up to a 10-fold increase in water production for each SWRS unit and robust operation even in remote locations and with limited technical backup and perhaps changing water quality conditions. Low coagulant doses result in decreased transportation and storage requirements. In addition to practical application to the SWRS and similar operations, the results demonstrated the utility of quick step-flux tests for design and operation testing.

Effectiveness of priority PAH removal in a water coagulation process

The paper presents results of research on the removal of priority hazardous polycyclic aromatic hydrocarbons (PAHs) (anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[g,h,i]perylene, indeno[1,2,3-cd]pyrene) from water in the coagulation and sedimentation process. Coagulants chosen for the analysis were aluminum(VI)sulfate and two pre-hydrolyzed coagulants – FLOKOR 1.2A and FLOKOR 1ASW/B. Water samples subjected to coagulation were collected from selected water treatment plants following the pre-ozonation process. Tested coagulants were dosed at optimal doses (1.2; and 1.8 mg Al3+/L). The process was carried out at optimum parameters: rapid mixing – 3 min at the rotational speed of 200 rpm; slow mixing – 10 min at 30 rpm; sedimentation – 60 min. Summary concentration of six priority hazardous PAHs in water after pre-ozonation amounted to 12.6 ng/L; after volumetric coagulation using selected coagulants it was in the range 6.8–8.3 ng/L. The highest efficiency in the removal of priority hazardous aromatic hydrocarbons was obtained after application of the preparation FLOKOR 1 ASW/B. Decrease in the summary concentration amounted to 46.4%. For the removal of individual priority PAHs, FLOKOR 1ASW/B was also more effective using lower coagulant dose than was aluminum(VI)sulfate (decrease in the range 23.6%–56.1%).

Analysis and optimization of coagulation and flocculation process

Natural coagulants have been the focus of research of many investigators through the last decade owing to the problems caused by the chemical coagulants. Optimization of process parameters is vital for the effectiveness of coagulation process. In the present study optimization of parameters like pH, dose of coagulant and mixing speed were studied using natural coagulants sago and chitin in comparison with alum. Jar test apparatus was used to perform the coagulation. The results showed that the removal of turbidity was up to 99 % by both alum and chitin at lower doses of coagulant, i.e., 0.1–0.3 g/L, whereas sago has shown a reduction of 70–100 % at doses of 0.1 and 0.2 g/L. The optimum conditions observed for sago were 6 and 7 whereas chitin was stable at all pH ranges, lower coagulant doses, i.e., 0.1–0.3 g/L and mixing speed—rapid mixing at 100 rpm for 10 min and slow mixing 20 rpm for 20 min. Hence, it can be concluded that sago and chitin can be used for treating water even with large seasonal variation in turbidity.

Impacts of organic coagulant aid on purification performance and membrane fouling of coagulation/ultrafiltration hybrid process with different Al-based coagulants

Effects of polydimethyldiallylammonium chloride (PD) on coagulation behaviors of different Al-based coagulants were investigated in coagulation–ultrafiltration (C–UF) hybrid process, regarding the impurity removal efficiency, floc properties and membrane foulings. Floc characteristics, including floc size, compact degree, strength and re-growth ability were studied using a laser diffraction particle sizing device. Resistance analyses were implemented to explore the membrane fouling mechanisms. The results indicated that PD aid could increase the purification efficiency of C–UF, especially at low coagulant doses. PD–alum/PD–PACl contributed to large flocs, while alum–PD/PACl–PD gave rise to flocs with high Rf and Df values. The results of ultrafiltration experiments showed that conventional coagulant, i.e., alum led to a flux reduction of 52%; while the reductions for alum–PD and PD–alum were 53% and 34%, respectively. The flux reductions for PACl, PACl–PD and PD–PACl were 60%, 57% and 39%. Flux declines became more severe when the coagulated suspensions were exposed to increased shears and the suspensions coagulated by aluminum plus PD resulted in the least reductions in fluxes.

Synthesis and coagulation performance of composite poly-aluminum-ferric-silicate-chloride coagulants in water and wastewater

The aim of this work was to study the combination of an inorganic pre-polymerized coagulant (polyaluminum chloride [PACl]) with ferric species and polysilicic acid in various mixing orders Al/Fe/Si and OH/Al molar ratios, by applying two polymerization techniques for the production of a unique reagent, representing a more efficient coagulant than the respective commercially available (PACl-18) or laboratory-prepared (PACllab) for water or wastewater treatment. Several of coagulants’ derivatives were prepared and were examined by jar tests for the treatment of simulated surface water, contaminated by clay particles (turbidity) and humic acid (natural organic matter); pH, turbidity, UV254 nm absorbance, and residual Al were measured in the treated water. PSiFAC1.5:10:15 prepared by the co-polymerization technique was found to be the most efficient coagulant from all the tested compounds; in addition, no flocculant aid (polyelectrolyte) was required with this product. Low coagulant doses, about 1.5–2 mg/L were required for the reduction of turbidity values to lower than 1 NTU; furthermore, PSiFAC1.5:10:15 resulted in low residual aluminum concentration (about 140 μg Al/L). The most effective coagulants obtained were also used for the treatment of tannery wastewater to evaluate their performance and it was observed that high turbidity removal (~99%) was obtained at doses of about 100 mg/L. The most effective coagulants are under study for their potential use to alleviate membrane fouling in MBRs.

Removal of metronidazole antibiotic from contaminated water using a coagulant extracted from Plantago ovata

A coagulant was successfully extracted from Plantago ovata by a method using a FeCl3-induced crude extract (FCE). FCE was investigated for its coagulation potential to remove metronidazole (MNZ) from water. Tests were done to evaluate the effects of solution pH, FCE dose, MNZ concentration, and solution temperature on removal of MNZ by FCE. A low coagulant dose, 1.75 mg/L, achieves a high MNZ removal percentage, 89.3%, at neutral pH and room temperature. MNZ removal by FCE increased from 18 to 89.3% with increased FCE quantity from 0.75 to 1.75 mg/L. The low concentration of MNZ, 10 mg/L, was completely removed by FCE. Coagulant process did not depend on water temperature. The sludge volumetric index and sludge volume were also studied. Overall, the results indicate that developed FCE was an efficient coagulant that presents an attractive coagulant method for application in treating contaminants in water.

Optimisation of coagulation/flocculation for pre-treatment of high strength and saline wastewater: Performance analysis with different coagulant doses

Abstract In this study, the coagulation and flocculation processes were evaluated in the treatment of slops with the aim of reducing the organic concentration in the pre-treated influent, as measured by Chemical Oxygen Demand (COD), Total Organic Carbon (TOC) and Total Petroleum Hydrocarbons (TPH). The coagulation was optimised for the wastewaters sampled from a floating tank of an oil costal deposit in the Augusta Harbour (Sicily-Italy). The jar test experiments were run at 200 rpm for 1 min, 30 rpm for 20 min and settling for 180 min. Two different trivalent salts were used as the coagulant: FeCl3 and Al2(SO4)3 × 18H2O. To limit the residual concentration of Al and Fe after coagulation, a low coagulant dose was used. Furthermore, both anionic and cationic polyelectrolytes were used as flocculating agents. In general, the application of the coagulation process with low coagulant doses was effective in the pre-treatment of the slops. In fact, the percentages of removal, although rarely exceeding 70–80% (in term of TOC), reduced the organic load resulting from recalcitrant or poorly biodegradable substances. In particular a pre-treatment, with aluminium sulphate is more versatile for the removal of the main contaminants, that can hinder the performance of subsequent biological processes.

Effect of coagulation on fouling potential and removal of algal organic matter in ultrafiltration pretreatment to seawater reverse osmosis

This paper investigated the effect of coagulation on fouling potential and removal of algal organic matter (AOM) in seawater ultrafiltration (UF) systems. AOM harvested from a strain of bloom forming marine diatom, Chaetoceros affinis, was coagulated with ferric chloride under different coagulation modes and conditions. The effect of coagulation on fouling potential was determined with the Modified Fouling Index-Ultrafiltration (MFI-UF). Removal of AOM was studied for three different modes of coagulation, namely, coagulation followed by sedimentation, coagulation followed by sedimentation and filtration through 0.45 μm, and inline coagulation followed by filtration through 150 kDa UF membranes. Liquid chromatography – organic carbon detection was used to determine the removal of AOM with particular emphasis on biopolymers.AOM (as biopolymers) had a high fouling potential as measured by MFI-UF, which strongly depended on filtration flux. Moreover, the developed cake/gel layer on the membrane was fairly compressible during filtration; manifested as higher fouling potential at higher filtration flux and non-linear development of pressure in filtration tests.Coagulation substantially reduced fouling potential and compressibility of the AOM cake/gel layer. The impact of coagulation was particularly significant at coagulant doses >1 mg Fe/L. Coagulation also substantially reduced the flux-dependency of AOM fouling potential, resulting in linear development of pressure in filtration tests at constant flux. This was attributed to adsorption of biopolymers on precipitated iron hydroxide and formation of Fe-biopolymer aggregates, such that the fouling characteristics of iron hydroxide precipitates prevailed and AOM fouling characteristics diminished. At low coagulant dose, inline coagulation/UF was more effective in removing AOM than the other two coagulation modes tested. At high coagulant dose where sweep floc conditions prevailed, AOM removal was considerably higher and controlled by coagulant dose rather than coagulation mode.

Treatment of steam-assisted gravity drainage water using low coagulant dose and Fenton oxidation

The use of coagulation and Fenton oxidation was studied for total organic carbon (TOC) and silica removal from steam-assisted gravity drainage (SAGD) water at 80°C and two different concentrations replicating the stream feeding the warm lime softening unit having 675 mg/L TOC and 350 mg/L silica and the blowdown of the once through steam generator having 3700 mg/L TOC and 2585 mg/L silica. Coagulation was carried out by the addition of FeCl3, Al(NO3)3 or Ca(NO3)2. The results showed that Fe(III) salt outperformed Al(III) and Ca(II) salts. A two-stage addition of 2.5 g FeCl3 per g TOC intermediated by a filtration unit resulted in approximately 72% TOC removal and more than 80% silica removal while maintaining low solid waste. Comparing results pertaining to coagulant concentration and final pH, it can be easily concluded that silica removal is governed by the resultant pH, whereas TOC removal was accomplished through surface neutralization and localized enmeshment coagulation. Fenton oxidation is proposed to further treat the filtrate obtained from the second stage Fe(III) coagulation. An additional 10% TOC removal could be achieved; at seven times lower H2O2 dose in the presence of Fe 2+ or Fe0 reagent. Moreover, the advanced Fenton process resulted in high silica removal as a result of adsorption onto Fe(OH)3 precipitate, which formed at the equilibrium pH of the system.

Removal of chemical oxygen demand from textile wastewater using a natural coagulant

A biomaterial was successfully synthesized from Plantago ovata by using an FeCl3-induced crude extract (FCE). The potential of FCE to act as a natural coagulant was tested for the pretreatment of real textile wastewater. Tests were performed to evaluate the effects of FCE quantity, salt concentration, and wastewater pH on chemical oxygen demand (COD) reduction during a coagulation/flocculation process. Experimental results indicated that the wastewater could be effectively treated by using a coagulation/flocculation process, where the BOD5/COD ratio of the effluent was improved to 0.48. A low coagulant dose, 1.5mg/L, achieved a high COD removal percentage, 89%, at operational conditions of neutral pH and room temperature. The experimental data revealed that the maximum COD removal occurred at water pH<8. Increasing the salt promoted the COD removal. The settling and filterability characteristics of the sludge were also studied. Scanning electron microscopy and energy dispersive spectroscopy studies were conducted to determine the sludge structure and composition, respectively. Overall, FCE as an eco-friendly biomaterial was revealed to be a very efficient coagulant and a promising option for the removal of COD from wastewaters.