scholarly journals Removal of Fluoride from Drinking Water Using Modified Immobilized Activated Alumina

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Aneeza Rafique ◽  
M. Ali Awan ◽  
Ayesha Wasti ◽  
Ishtiaq A. Qazi ◽  
Muhammad Arshad
Keyword(s):  
Drinking Water ◽  
Removal Efficiency ◽  
Activated Charcoal ◽  
Contact Time ◽  
Sol Gel ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Batch Adsorption ◽  
Activated Alumina ◽  
Fluoride Adsorption

The study describes the removal of fluoride from drinking water using modified immobilized activated alumina (MIAA) prepared by sol-gel method. The modification was done by adding a specific amount of alum during the sol formation step. The fluoride removal efficiency of MIAA was 1.35 times higher as compared to normal immobilized activated alumina. A batch adsorption study was performed as a function of adsorbent dose, contact time, stirring rate, and initial fluoride concentration. More than 90% removal of fluoride was achieved within 60 minutes of contact time. The adsorption potential of MIAA was compared with activated charcoal which showed that the removal efficiency was about 10% more than the activated charcoal. Both the Langmuir and Freundlich adsorption isotherms fitted well for the fluoride adsorption on MIAA with the regression coefficientR2of 0.99 and 0.98, respectively. MIAA can both be regenerated thermally and chemically. Adsorption experiments using MIAA were employed on real drinking water samples from a fluoride affected area. The study showed that modified immobilized activated alumina is an effective adsorbent for fluoride removal.

Removal of Fluoride from Drinking Water by Gel Composite of Metal Ion and Humic Acid Adsorbent

2013 ◽  
Vol 726-731 ◽  
pp. 695-699
Author(s):  
Li Hong ◽  
Si Xiang Wang ◽  
Yong Liu ◽  
Yue Chun Zhang
Keyword(s):  
Drinking Water ◽  
Humic Acid ◽  
Contact Time ◽  
Metal Ion ◽  
Fluoride Removal ◽  
Batch Adsorption ◽  
Solution Ph ◽  
Adsorption Method ◽  
Sem Images ◽  
Fluoride Adsorption

Humic acid adsorbent modified with metal ions was prepared by gel polymerization and named gel composite of metal ion and humic acid, which abbreviated GCMH to uptake fluoride from drinking water. The samples were measured by X-ray diffraction (XRD) patterns and scanning electron microscope (SEM) images. Fluoride adsorption onto the synthesized samples was investigated by batch adsorption method. In previous works, detailed studies were carried out to investigate the effect of contact time, adsorbent dose, initial solution pH, temperatures and co-existing anions. The maximum fluoride removal was obtained at pH7. Presence of HCO3− adversely affected the adsorption of fluoride. The optimum absorption conditions were at the dose of 10g/L, temperature of water of 55°Cand contact time of 6hs.

scholarly journals Eggshell-Derived Nanohydroxyapatite Adsorbent for Defluoridation of Drinking Water from Bofo of Ethiopia

2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Kifle Workeneh ◽  
Enyew Amare Zereffa ◽  
Toshome Abdo Segne ◽  
Rajalakshmanan Eswaramoorthy
Keyword(s):  
Removal Efficiency ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Batch Adsorption ◽  
Alternative Source ◽  
Fluoride Adsorption ◽  
Initial Ph ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Eggshell Waste

Fluoride has become a notable toxicological environmental hazard worldwide because it is often found in groundwater. In the present study, hydroxyapatite adsorbent was synthesized from eggshell waste to remove fluoride from aqueous solution. XRD, FT-IR, and TGA techniques were used to characterize the prepared adsorbent. Batch adsorption studies were performed to examine the adsorption capacity of hydroxyapatite such as the effect of the initial pH of the solution, contact time, adsorbent dose, and initial fluoride concentration. The fluoride ion-selective electrode was used to determine the fluoride removal efficiency. 98.8% of fluoride was removed at pH 3.0, but at pH ~7.0, 85% of fluoride was removed; it shows that the fluoride adsorption is pH dependent. The adsorption isotherm studies (Langmuir and Freundlich models) and the experimental results for the removal of fluoride showed that the Langmuir model was more favorable and the reaction followed pseudo-second-order kinetics. In real water samples, the prepared hydroxyapatite derived from eggshell exhibited 81% removal efficiency. Our results indicate that eggshell waste-derived hydroxyapatite may be an alternative source for defluoridation in developing countries.

scholarly journals An Experimental Study on Biosorption of Fluoride from Water Using LocallyObtained Moringa Oleifera Seeds

2021 ◽  
Vol 19 (1) ◽  
pp. 35-39
Author(s):  
Faheem Akhter ◽  
Arsalan A. Jokhio ◽  
Javed A. Noonari
Keyword(s):  
Aqueous Solution ◽  
Removal Efficiency ◽  
Contact Time ◽  
Moringa Oleifera ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Engineering Science ◽  
Environment Friendly ◽  
Experimental Facilities ◽  
Adsorbent Dose

Moringa Oleifera is considered to be a natural bio-adsorbent. Unlike chemical coagulants, Moringa Oleifera seeds are environment friendly with various other advantages. The present study investigated the fluoride removal efficiency of Moringa Oleifera from water. Influence of adsorbent dose (1, 2, 4 g/L), contact time (20, 40 and 60 min) and initial fluoride concentration (2 and 5 mg/L) over removal efficiency were determined and optimized. It was found that increased adsorbent dose and contact time enhanced the removal efficiency which is in agreement with the previous studies. The highest removal of 88.1% was achieved when the adsorbent dose and contact time were optimized to 4 g/L and 60 minutes with an initial fluoride concentration of 2 mg/L. The results showed that Moringa Oleifera can be used as an environment friendly, cheap and effective bio-adsorbent for fluoride removal from aqueous solution. All the experimental facilities were provided by Bio-Fuel Lab, Energy & Environment Department, Quaid-e-Awam University of Engineering, Science and Technology, Nawabshah, Pakistan. The samples were analyzed at the Pakistan Council of Research in Water Resources (PCRWR), Tando Jam, Pakistan.

scholarly journals Fluoride removal efficiency of Tulsi (Ocimum Sanctum) from water

2021 ◽  
Author(s):  
Kefelegn Bayu ◽  
Abraham Geremew ◽  
Wegene Deriba ◽  
Yohannes Mulugeta ◽  
Samuel Wagari ◽  
...  
Keyword(s):  
Drinking Water ◽  
Removal Efficiency ◽  
Natural Water ◽  
Water Samples ◽  
Contact Time ◽  
Ocimum Sanctum ◽  
Fluoride Removal ◽  
Initial Concentration ◽  
Natural Water Samples ◽  
Adsorbent Dose

Abstract Fluoride concentration in drinking water higher than recommended value imposes different health problems and there are advanced and chemical based defluoridation techniques even if they are not feasible for developing countries and have limitations. Due to this, defluoridation by using locally available plants is one of the most efficient and sustainable options. Therefore, the current study was intended to investigate fluoride removal efficiency of Tulsi (Ocimum Sanctum) from water that can be an alternative means to reduce the problem related to its high concentration. A laboratory based experimental study was implemented by using potentiometric determination in Haramaya University. The leaves of Tulsi were collected, washed with tap water, rinsed with distilled water, and then were dried at room temperature, crushed and sieved through 500-μm stain-less steel sieve. The experiments were conducted on artificially fluoridated water by anhydrous fluoride and natural water samples collected from deep well water sources from Adama and Harar town. Data was analyzed using Design of Expert (DOE) and Microsoft excel. Twenty-nine runs for aqueous solution were conducted at different factor combinations and the optimum combinations were applied for natural water samples. The study depicts that plant has an efficiency of removing 68.4% of fluoride from water. The best factor combinations to achieve this efficiency was 0.2 g/100 ml, 22.6 min, 5.7 and 6.6 mg/l, adsorbent dose, contact time, pH and initial concentration respectively. pH and initial concentration have a negative effect and adsorbent dose and contact time have a positive effect on removing fluoride from water. Hence, people living in fluorosis endemic areas can use the processed plant as a de-fluoridating agent to minimize adverse health effects. HIGHLIGHT This research articles paves way to further study to remove contaminants from water, wastewater, which can pose a substantial effect on public health. The study conducted to investigate removal mechanism of fluoride from drinking water with low cost locally available plant and the software technologies were applied to find the optimum conditions at which the adsorbent works best.

scholarly journals Enhanced fluoride removal from drinking water in wide pH range using La/Fe/Al oxides loaded rice straw biochar

2021 ◽  
Author(s):  
Nan Zhou ◽  
Xiangxin Guo ◽  
Changqing Ye ◽  
Ling Yan ◽  
Weishi Gu ◽  
...  
Keyword(s):  
Drinking Water ◽  
Rice Straw ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Batch Adsorption ◽  
Solution Ph ◽  
Adsorption Sites ◽  
Wide Ph Range ◽  
Rice Straw Biochar ◽  
Ph Range

Abstract A novel and highly efficient adsorbent was prepared by loading La/Fe/Al oxides onto rice straw biochar (RSBC) and was tested for the ability to remove fluoride from drinking water. Characterized by SEM, XRD, Zetapotential and FTIR, it was found that the ternary metal oxides were successfully loaded on the surface of biochar in amorphous form, resulting in the formation of hydroxyl active adsorption sites and positive charges, which played a synergistic role in fluoride removal. Through batch adsorption tests, key factors including contact time, initial fluoride concentration, initial pH and co-existing anions effects were investigated. Results showed that the tri-metallic modified biochar (La/Fe/Al-RSBC) had excellent fluoride removal performance with an adsorption capacity of 111.11 mg/g. Solution pH had little impacts on the removal of fluoride, the adsorbent retained excellent fluoride removal capacity in a wide pH range of 3.0–11.0. The co-existing anions had almost no effect on the fluoride removal by La/Fe/Al-RSBC. In addition, La/Fe/Al-RSBC could be regenerated and reused. Electrostatic adsorption and ion exchange were responsible for this adsorption behavior. These findings suggested the broad application prospect of a prepared biochar adsorbent based on rare earth and aluminum impregnation for the fluoride removal from drinking water.

scholarly journals Effects of Calcination Temperature of Naturally Occurring Absorbents on Drinking Water Defluoridation

2020 ◽  
Vol 39 (2) ◽  
pp. 165-176
Author(s):  
Brenda Mndolwa ◽  
Felix Mtalo
Keyword(s):  
Drinking Water ◽  
Calcination Temperature ◽  
Removal Efficiency ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Treated Water ◽  
Calcination Temperatures ◽  
Natural Adsorbents ◽  
Different Temperatures ◽  
Water Quality Deterioration

Currently, in Tanzania, fluoride removal from drinking water is treated mostly using the bone char method. The method has poor acceptability in some religious communities and also causes water quality deterioration in taste and odour if the bones are not properly prepared. The use of local natural adsorbents as an alternative is feasible with limitations of high levels of other impurities in treated water. Locally available gypsum, magnesite and bauxite were converted to adsorbents through calcination. The study was conducted to determine the removal efficiency, best calcination temperature and composite ratio of the three adsorbents for the removal of fluoride from natural drinking water with fluoride concentration as high as 16.7 mg/L. The adsorbent materials were calcined at different temperatures ranging between 3500C and 6000C. Batch experiments were performed and samples were collected at different contact time intervals of 2 minutes to 60 minutes, and residual fluoride was determined. Bauxite had the highest fluoride removal efficiency compared to gypsum and magnesite. The best calcination temperatures were 3500C, 4000C, 6000C for gypsum, bauxite and magnesite, respectively. The best calcination temperatures were used to prepare composites at different ratios of 1:2:3, 2:3:1 and 3:2:1, bauxite: gypsum: magnesite respectively. All the ratios gave low sulphate and iron as impurities within the recommended standards. The composites lowered fluoride concentration level to 1.53 mg/L, 2.07 mg/L, 2.60 mg/L for 1:2:3, 2:3:1, 3:2:1 ratios, respectively. In conclusion the study reveals that, it is possible for composites made of adsorbent calcinated at different optimum temperatures to give good results in fluoride removal from drinking water, as well as standard pH, iron and sulphate values in treated water.

scholarly journals Synthesis and characterization of aluminum-based adsorbent and application in fluoride removal from aqueous solution

2020 ◽  
Vol 10 (1) ◽  
pp. 46-61 ◽  
Author(s):  
Jihane Assaoui ◽  
Zineb Hatim ◽  
Abdelmoula Kheribeche
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Fluoride Concentration ◽  
Infrared Spectrometry ◽  
Fluoride Removal ◽  
Batch Adsorption ◽  
X Ray ◽  
Wide Range ◽  
Adsorbent Dose

A novel adsorbent was obtained by a facile precipitation method and was used for fluoride removal from aqueous solution. Mineralogical and physicochemical characterization of the adsorbent was carried out by X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), Energy Dispersive X-Ray attached to Scanning Electron Microscopy (SEM-EDX), BET Specific Surface Area(SSAN2BET) analysis and Fourier-Transform Infrared Spectrometry (FTIR). The effect of various operational parameters such as contact time, initial fluoride concentration, (20-160 mg L-1) adsorbent dose (1-6 g L-1) and initial pH solution (3-11) was evaluated in batch procedures at room temperature (25±2°C). The results of the batch adsorption experiments proved that 24 h of contact time was sufficient for attaining equilibrium. The maximum wastewater defluoridation (84.91%) was obtained for 40 mg L-1 and 3 g L-1 of initial fluoride concentration and adsorbent dose, respectively. It appears that there was no significant effect on the F- removal over a wide range of pH 3-11. Kinetic studies revealed that fluoride adsorption fitted well to pseudo-second-order. The adsorption isotherm of fluoride sorption indicated that the maximum adsorption capacity was noted to be 43.29 mg g-1. Batch adsorption data was better described by Langmuir isotherm confirming monolayer adsorption with homogenous distribution of active sites and without interaction between adsorbed molecules. The obtained results indicated that the ion exchange is probably the main mechanism involved in the F- adsorption by the aluminium-based adsorbent.

scholarly journals Aluminum oxyhydroxide-doped PMMA hybrids powder prepared via facile one-pot method towards copper ion removal from aqueous solution

2019 ◽  
Vol 9 (4) ◽  
pp. 317-325 ◽  
Author(s):  
Misagh Ghamari ◽  
Amin Imani ◽  
James F. Williams ◽  
Mahdi Ghasemifard
Keyword(s):  
Removal Efficiency ◽  
Contact Time ◽  
Copper Ions ◽  
Sol Gel ◽  
Copper Ion ◽  
Batch Adsorption ◽  
One Pot ◽  
Ion Removal ◽  
Adsorption Performance ◽  
Enhanced Adsorption

Abstract A novel polymethyl methacrylate/boehmite nanocomposite with remarkably enhanced adsorption performance of Cu(II) was synthesized from $${\text{Al}}({\text{NO}}_{3} )_{3} \cdot 9{\text{H}}_{2} {\text{O}}$$Al(NO3)3·9H2O using a facile sol–gel method. The effects of boehmite content, contact time and morphology of hybrid (pH of synthesis) as the main parameters on removal efficiency and removal capability of hybrid on copper ions have been explored. Composites contained between 0.7 and 5wt% boehmite content and those with dissimilar morphology prepared with different pH values showed different adsorption behavior. Batch adsorption experiments show that the adsorption performance of the hybrids was enhanced with increased boehmite and contact time. The highest removal efficiency and adsorption capability were achieved when the hybrid was prepared at pH 8 with associated increased catalytic activity. Graphic abstract

scholarly journals Fluoride Adsorption by Pumice from Aqueous Solutions

2012 ◽  
Vol 9 (4) ◽  
pp. 1843-1853 ◽  
Author(s):  
Amir Hossein Mahvi ◽  
Behzad Heibati ◽  
Alireza Mesdaghinia ◽  
Ahmad Reza Yari
Keyword(s):  
Drinking Water ◽  
Aqueous Solutions ◽  
Fluoride Concentration ◽  
Freundlich Isotherm ◽  
Fluoride Removal ◽  
Maximum Sorption Capacity ◽  
Fluoride Adsorption ◽  
Maximum Sorption ◽  
Pseudo Second Order ◽  
High Concentrations

Drinking water provides many vital elements for the human body, but the presence of some dissolved elements more than permissible concentration can endanger human health. Among the dissolved elements in drinking water, fluoride is noticeable, because both the very low or very high concentrations have adverse health impacts such as dental caries. Therefore, fluoride concentration should be kept in acceptable levels. In this study Pumice was used for fluoride removal. It was found that Fluoride sorption kinetic was fitted by pseudo-second-order model. The maximum sorption capacity of Pumice was found to be 13.51 mg/g at laboratory temperature (24°C). Maximum sorption study occurred at pH= 3. Results of Isotherm showed the fluoride sorption has been well fitted with Freundlich isotherm model. This study has demonstrated that Pumice can be used as effective adsorbents for fluoride removal from aqueous solutions. The adsorbent prepared in this study was cheap and efficient in removal of fluoride than other adsorbents.

Utilisation of Biomass and Hybrid Biochar from Elephant Grass and Low Density Polyethylene for the Competitive Adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) from Aqueous Media

2020 ◽  
Vol 13 ◽  
Author(s):  
Joshua O. Ighalo ◽  
Lois T. Arowoyele ◽  
Samuel Ogunniyi ◽  
Comfort A. Adeyanju ◽  
Folasade M. Oladipo-Emmanuel ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Removal Efficiency ◽  
Contact Time ◽  
Competitive Adsorption ◽  
Adsorption Process ◽  
Aqueous Media ◽  
Polluted Water ◽  
Batch Adsorption ◽  
Order Kinetic ◽  
Elephant Grass

Background: The presence of pollutants in polluted water is not singularized hence pollutant species are constantly in competition for active sites during the adsorption process. A key advantage of competitive adsorption studies is that it informs on the adsorbent performance in real water treatment applications. Objective: This study aims to investigate the competitive adsorption of Pb(II), Cu(II), Fe(II) and Zn(II) using elephant grass (Pennisetum purpureum) biochar and hybrid biochar from LDPE. Method: The produced biochar was characterised by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The effect of adsorption parameters, equilibrium isotherm modelling and parametric studies were conducted based on data from the batch adsorption experiments. Results: For both adsorbents, the removal efficiency was >99% over the domain of the entire investigation for dosage and contact time suggesting that they are very efficient for removing multiple heavy metals from aqueous media. It was observed that removal efficiency was optimal at 2 g/l dosage and contact time of 20 minutes for both adsorbent types. The Elovich isotherm and the pseudo-second order kinetic models were best-fit for the competitive adsorption process. Conclusion: The study was able to successfully reveal that biomass biochar from elephant grass and hybrid biochar from LDPE can be used as effective adsorbent material for the removal of heavy metals from aqueous media. This study bears a positive implication for environmental protection and solid waste management.

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