Use of Acorn Leaves as a Natural Coagulant in a Drinking Water Treatment Plant

Removal of lead in water by coagulation flocculation process using Cactus-based natural coagulant: optimization and modeling by response surface methodology (RSM)

The aim of this research is to study the ability of Cactus leaves to act as a biocoagulants for the removal of lead in water. Different solvents, such as distilled water, NaCl, NaOH, and HCl, were used as chemical activators to extract the active components from the Cactus. The Cactus was utilized as an organic coagulant in five different forms: (i) Cactus juice (CJ); Cactus extract using (ii) distilled water (C-H2O); (iii) NaCl at 0.5 M concentration (C-NaCl); (iv) NaOH at 0.05 M concentration (C-NaOH); and (v) HCl at 0.05 M concentration (C-HCl). In order to establish the optimal conditions for the coagulation, this study employed the jar test as an experimental technique and the Box-Behnken design (BBD) as an experimental approach. According to BBD, there are three factors (k = 3), namely pH, biocoagulant dosage, and settling time. The R2 and R2 adjusted for all coagulants were close to 100%, confirming the validity of all the mathematical models. The results were significant; the highest lead removal efficiencies were 98.11%, 98.34%, 95.65, 96.19%, and 97.49%, utilizing CJ, C-H2O, C-NaCl, C-HCl, and C-NaOH as natural coagulants. The Cactus has been characterized using FTIR, XRD, and SEM to identify the active components that remove lead.

Modeling and optimization of the coagulation/flocculation process in turbidity removal from water using poly aluminum chloride and rice starch as a natural coagulant aid

The application of the coagulation/flocculation process is very important due to its simplicity in removing turbidity. Due to the disadvantages of using chemical coagulants in water and the lack of sufficient effect of natural materials alone in removing turbidity for proper performance, the simultaneous use of chemical and natural coagulants is the best way to reduce the harmful effects of chemical coagulants in water. In this study, the application of poly aluminum chloride (PAC) as a chemical coagulant and rice starch as a natural coagulant aid to remove turbidity from aqueous solutions was investigated. Effects of the above coagulants on the four main factors, coagulant dose (0-10 mg/L), coagulant adjuvant dose (0-0.1 mg/L), pH (5-9), turbidity (NTU 0-50), and each five levels were assessed using a central composite design (CCD). Under the optimized conditions, the maximum turbidity elimination efficiency was found to be 96.6%. The validity and adequacy of the proposed model (quadratic model) were confirmed by the corresponding statistics (i.e., F-value of 23.3, p-values of 0.0001, and lack of fit of 0.877 for the model, respectively, R2 = 0.88, R2adj. = 0.84, R2 pred = 0.79, AP = 22.04).

Coagulation activity of liquid extraction of Leucaena leucocephala and Sesbania grandiflora on the removal of turbidity

Turbidity is removed by adding a chemical coagulant, which produces a secondary toxic of alumina residues in the water. Therefore, the aim of study was to evaluate the coagulation activity of NaCl extract from Leucaena leucocephala and Sesbania grandiflora seeds on the removal of turbidity for water purification. The proximate composition of the seeds was determined. Fourier transform infrared spectroscopy was used to identify the functional groups of protein, and the surface morphology was observed by SEM-EDS. To obtain the optimized condition, all experiments were evaluated by artificial turbid water before being applied on the natural water (i.e., Selokan Mataram). The coagulation process was evaluated by concentration (M), dosage (mL/L), and pH in terms of turbidity, total dissolved solids, and transmittance of light. The results showed that both coagulant seeds contained 25.32 and 30.81% of protein. These coagulants could remove the turbidity by 99.7% for L. leucocephala and 94.24% for S. grandiflora from artificial turbid water at the optimized concentration of 1.0 M, and dosage of 5 and 10 mL/L, respectively. At pH 5 the removal of turbidity from Selokan Mataram was 99.4% for L. leucocephala and 97.23% for S. grandiflora.

The Adsorptive Removal of Bengal Rose by Artichoke Leaves: Optimization by Full Factorials Design

Currently, the dye industry is increasing its production as a consequence of the growing need for their products in different manufacturing sectors, such as textiles, plastics, food, paper, etc... Thereafter, these industries generate very large volumes of effluents contaminated by these dyes, which require proper removal treatment before final discharge of the effluents into the environment. In this study, artichoke leaves were used as an economical and eco-friendly bio-adsorbent for Bengal Rose (BR) dye removal. Bio-adsorbent obtained from artichoke leaves was ground to powder size. The resulting powder was characterized by different methods, such as Brunauer-Emmett-Teller (BET) surface area analysis, scanning electron microscopy(SEM), X-ray Diffraction (XRD), Fourier transfer infrared (FTIR), pH at point of zero charge (pHpzc), equilibrium pH, iodine number, methylene blue number, phenol number, density, Energy dispersive X-ray spectroscopy (EDX) and Thermo-gravimetric analysis (TGA). Thereafter, the bio-adsorbent was used to study its capability for removing BR dye by testing contact time, initial concentration of dye and temperature. The results show that the saturation of bio-sorbent was reached after 40 min and the removal rate of BR dye by artichoke leaves powder (ALP) was 4.07 mg/g, which corresponds to a removal efficiency of 80.1%. A design of experiences (DOE) based on a two-level full factorial design (23) was used to study the effects of different parameters, such as pH, temperature and bio-adsorbent dosage on BR dye removal efficiency. The obtained results show that the highest removal efficiency was 86.5% for the optimized values of pH (4), temperature (80 °C) and bio-adsorbent dosage (8 g/L). Furthermore, a satisfying accordance between experimental and predicted data was observed. The kinetic and isotherm studies show that the pseudo-second order model simulated adequately the obtained data and it was found that Langmuir and Temkin isotherm models are liable and suitable for evaluating the adsorption process performance. Free energy change of adsorption (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) were furthermore calculated to predict the nature of the adsorption process.

Potential of local plant leaves as natural coagulant for turbidity removal

The performance of local plants was tested using synthetic turbid water resembling real wastewater by measuring their ability to remove turbidity. The selected plants were A. indica, S. palustris, D. linearis, S. polyanthum, M. esculenta, P. sarmentosum, and M. malabathricum which can easily be found locally. The experiment was run based on coagulant dosages varied from 0 to 10 g/L for each plant with a rapid mixing speed at 180 rpm for 3 min, slow mixing speed at 10 rpm for 20 min, and settling time for 30 min. The results demonstrated that each plant has been capable of reducing turbidity by different amounts, with an increase in the coagulant dosage. The optimum coagulant dosages achieved for A. indica, S. palustris, S. polyanthum, and D. linearis were 10 g/L with turbidity removal at 26.9%, 24.9%, 24.9%, and 17.5%, respectively. P. sarmentosum and M. esculenta attained optimum coagulant dosages at 5 g/L with turbidity removal at 24.2% and 22.2%, and lastly M. malabathricum at 0.1 g/L (12.2%). P. sarmentosum was suggested to the best natural coagulant which achieved the highest removal of turbidity with a low dosage used.

Comparing the Coagulation Performance of Rice Husk, Cypress Leaves, and Eucalyptus Leaves Powders with That of Alum in Improving the Turbidity and pH of Some Local Water Sources in Bamenda, Cameroon

In this study, the efficiencies of the use of rice husk, cypress, and Eucalyptus leaves biocoagulants as alternative to alum as chemical coagulant in reducing turbidity and stabilizing the pH of slaughterhouse wastewater and three other local drinking water sources were investigated. Two systems were used: one involving individual coagulants and the second involving mix alum and biocoagulant with fixed alum dose of 0.05 g and varying amounts of each biocoagulant type (0.05 to 5 g). Turbidity reduction, coagulation activity, and pH variation were used to characterize each system. Results show reduction in turbidity is higher in mixed coagulants than with individual coagulants. At 5 g each of alum, rice husk, cypress, and Eucalyptus leaves, the corresponding turbidity values, 8.3, 13.6, 14.5, and 20.3 NTU, were obtained compared to 7.3 with 0.05 alum and 5 g rice husk mixture, 8.7 NTU with 0.05 g alum and 5 g cypress leaves mixture, and 16.1 NTU with 0.05 g alum and 5 g Eucalyptus leaves mixture, for 37.3 NTU initial turbidity. The used biocoagulants individually show insignificant effect on the pH of coagulation-treated water. Alum has an insignificant effect up to 2 g. 0.05 g of each biocoagulant stabilizes the pH between 6.57 and 7.34 against 4.14 for alum. 0.05 g alum/0.05 g biocoagulant stabilized the pH of water between 6.32 and 7.41. The coagulation activities for individual systems follow the order alum > rice husk > cypress > Eucalyptus, and for mixed systems, alum/rice husk > alum/cypress > alum/Eucalyptus. Water with turbidity and pH values within the World Health Organization’s guideline value of < 5 NTU and 6.5–8.5, respectively, were obtained using studied low cost and locally available biocoagulants.

Use of Aloe vera as an Organic Coagulant for Improving Drinking Water Quality

The coagulation–flocculation–sedimentation process is widely used for removal of suspended solids and water turbidity reduction. The most common coagulants used to conduct this process are aluminum sulfate and ferric sulfate. In this paper, the use of Aloe vera as a natural-based coagulant for drinking water treatment was tested. The bio-coagulant was used in two different forms: powder as well as liquid; the latter was extracted with distilled water used as a solvent. The obtained results showed that the use of the natural coagulant (Aloe vera) in both powder (AV-Powder) and liquid (AV-H2O) forms reduced the water turbidity at natural pH by 28.23% and 87.84%, respectively. Moreover, it was found that the use of the two previous forms of bio-coagulant for drinking water treatment had no significant influence on the following three parameters: pH, alkalinity, and hardness. The study of the effect of pH on the process performance using Aloe vera as a bio-coagulant demonstrated that the maximum turbidity removal efficiency accounted for 53.53% and 88.23% using AV-Powder and AV-H2O, respectively, at optimal pH 6.

The Application of Modified Natural Polymers in Toxicant Dye Compounds Wastewater: A Review

The utilization of various types of natural and modified polymers for removing toxicant dyes in wastewater generated by the dye industry is reviewed in this article. Dye wastewater contains large amounts of metals, surfactants, and organic matter, which have adverse effects on human health, potentially causing skin diseases and respiratory problems. The removal of dyes from wastewaters through chemical and physical processes has been addressed by many researchers. Currently, the use of natural and modified polymers for the removal of dyes from wastewater is becoming more common. Although modified polymers are preferred for the removal of dyes, due to their biodegradability and non-toxic nature, large amounts of polymers are required, resulting in higher costs. Surface-modified polymers are more effective for the removal of dyes from the wastewater. A survey of 80 recently published papers demonstrates that modified polymers have outstanding dye removal capabilities, and thus have a high applicability in industrial wastewater treatment.

Red Lentil (Lens culinaris) Extract as a Novel Natural Coagulant for Turbidity Reduction: An Evaluation, Characterization and Performance Optimization Study

Increasing awareness on the detrimental effects of inorganic chemical coagulants and sustainable treatment have paved the way to develop environmentally-benign natural coagulants for water and wastewater treatment. In this research, brown, green, and red lentil (Lens culinaris) extracts have been evaluated as a natural coagulant for the turbidity reduction. The physicochemical characteristics properties of lentil extract were evaluated through field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), zeta potential analysis, and energy-dispersive X-ray (EDX) analysis. Red lentil extract was found to be an anionic polymer with hydroxyl and carboxyl functional groups. The effects of three major operating parameters, pH, the concentration of coagulant, and settling time, were studied and optimized through response surface methodology (RSM) using the Box–Behnken Design (BBD). The red lentil extract as coagulant was outperformed alum in acidic wastewater treatment, which achieved up to 98.87% turbidity removal with an optimum concentration of 26.3 mg/L in 3 min. Besides, the red lentil extract as coagulant reduced 29.42% of material cost, generated 15.6% lower amount of sludge and produced flocs with better settling characteristic (SVI: 7.39) as compared to alum. Based on the experimental observation and characterization study, absorption and bridging mechanisms were proposed for red lentil extract as the coagulant in turbidity reduction.

Waste Bricks Applied as Removal Agent of Basic Blue 41 from Aqueous Solutions: Base Treatment and Their Regeneration Efficiency

Waste brick materials were applied as removal materials of basic blue 41 (BB-41) from artificially contaminated water. They were characterized by different techniques prior their use. A series of removal tests were carried out at different conditions, such as a dosage effect, pH value, initial concentrations, and chemical treatment. The removal results indicated that the two untreated waste bricks had limited removal capacities of basic blue 41, ranging from 19 to 30 mg/g. However, these values were improved upon treatment with NaOH solution or by increasing the removal temperature. Waste brick collected from the Medina area (Med-WB) exhibited higher removal capacity compared to the one collected from the Jeddah area (Jed-WB), with a maximum removal capacity of 60 mg/g at 60 °C. The pH of the BB-41 solution also played an important factor, as it improved the removal amounts from 25 mg/g to 45 mg/g at initial concentration of 200 mg/L. The regenerative process was studied using oxidative reaction of the removed basic blue 41 with a solution of oxone and cobalt nitrate. The efficiency was maintained after 5 runs for Med-WB, with a slight variation of 25%, while it felt to 50% for Jed-WB material after three runs. These data indicate that the waste brick materials present as potential candidates for the dye removal and their origin has to be identified.