scholarly journals Characterisation of smectite-rich clay soil: Implication for groundwater defluoridation

2016 ◽  
Vol Volume 112 (Number 11/12) ◽  
Author(s):  
Rabelani Mudzielwana ◽  
Mugera W. Gitari ◽  
Titus A.M. Msagati ◽  
◽  
◽  
...  
Keyword(s):  
South Africa ◽  
Rural Areas ◽  
Contact Time ◽  
Clay Soil ◽  
Dental Fluorosis ◽  
Fluoride Concentration ◽  
Limpopo Province ◽  
World Health ◽  
Fluoride Removal ◽  
X Ray

Abstract Groundwater is a widely used and affordable source of drinking water in most of the rural areas of South Africa. Several studies have indicated that groundwater in some boreholes in South Africa has a fluoride concentration above the level recommended by the World Health Organization (1.5 mg/L). Fluoride concentrations above the permissible limit (>1.5 mg/L) lead to dental fluorosis, with even higher concentrations leading to skeletal fluorosis. In the present work, we evaluate the application of smectite-rich clay soil from Mukondeni (Limpopo Province, South Africa) in defluoridation of groundwater. The clay soil was characterised by mineralogy using X-ray diffraction, by elemental composition using X-ray fluorescence and by morphology using scanning electron microscopy. Surface area and pore volume was determined by the Brunauer–Emmett–Teller surface analysis method. Cation exchange capacity and pHpzc of the soil were also evaluated using standard laboratory methods. Batch experiments were conducted to evaluate and optimise various operational parameters such as contact time, adsorbent dose, pH and initial adsorbate concentration. It was observed that 0.8 g/100 mL of smectite-rich clay soil removed up to 92% of fluoride from the initial concentration of 3 mg/L at a pH of 2 with a contact time of 30 min. The experimental data fitted well to a Langmuir adsorption isotherm and followed pseudo second order reaction kinetics. Smectite-rich clay soil showed 52% fluoride removal from field groundwater with an initial fluoride concentration of 5.4 mg/L at an initial pH of 2 and 44% removal at a natural pH of 7.8. Therefore smectite-rich clay soil from Mukondeni has potential for application in defluoridation of groundwater. Chemical modification is recommended to improve the defluoridation capacity.

Fluoride removal from drinking water in Senegal: laboratory and pilot experimentation on bone char-based treatment

2011 ◽  
Vol 1 (4) ◽  
pp. 213-223 ◽  
Author(s):  
Sabrina Sorlini ◽  
Daniela Palazzini ◽  
Carlo Collivignarelli
Keyword(s):  
Drinking Water ◽  
Dental Fluorosis ◽  
Low Cost ◽  
Fluoride Concentration ◽  
Pilot Scale ◽  
Appropriate Technology ◽  
World Health ◽  
Fluoride Removal ◽  
Process Conditions ◽  
Bone Char

In Senegal there are four regions where fluoride concentration in drinking water exceeds the World Health Organization guide value of 1.5 mg/L. This generates permanent damages to the teeth (dental fluorosis) and to the skeleton (skeletal fluorosis). A safe, efficient, simple and low-cost effective defluoridation technique is not available yet and needs to be developed in order to prevent the occurrence of fluorosis. This experimental research was carried out in order to define an appropriate technology for fluoride removal from groundwater in Senegal. Batch tests and filtration tests at laboratory and pilot scale were carried out using animal bone char as adsorbent material for fluoride removal. Possible influencing parameters, such as specific ions in Senegalese drinking water, were investigated and the best process conditions were defined for the application in Senegal. The results attest to the efficacy of bone char in removing fluoride from Senegalese water: at pilot scale the mean specific adsorption was 2.7 mg F−/g of bone char, corresponding to a total treated volume of 4,000 L and a filter life of nearly three months.

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.

Development and Comparative Analysis of Aluminosilicate Based Ceramic Filters for Ground Water Defluoridation

2014 ◽  
Vol 936 ◽  
pp. 822-828 ◽  
Author(s):  
Johnson Kwame Efavi ◽  
Abu Yaya ◽  
Solomon Adeborna ◽  
Julius Fobil
Keyword(s):  
Ground Water ◽  
Contact Time ◽  
Dental Fluorosis ◽  
Fluoride Concentration ◽  
Fluoride Removal ◽  
Fluoride Ions ◽  
Ceramic Filters ◽  
Low Levels ◽  
Filter Thickness ◽  
Time Required

Low levels of fluoride in drinking water is healthy for the teeth enamel, however, higher concentrations result in dental fluorosis with prolonged exposures leading to skeletal fluorosis. Fluoride removal capacities of ceramic filters using aluminosilicates (Anfoega clay, Kibi kaolin, Laterite soil and Termitaria earth) samples from Ghana Geological Survey Department have been investigated and analysed for possible application in the Bongo District of Ghana noted forhavinghigh fluoride concentration in its ground water. Batch sorption studies conducted revealed that the amount of fluoride ions removed increased proportionally with increasing filter thickness, temperature and contact time to an optimum value. Using particle size ranges of <355μm and 1cm filter thickness at room temperature, the percentage of fluoride removed by the samples reached an optimum value after 70mins. Increases in filter thickness, contact time or temperatureincreased the amount of fluoride ions removedand the time required to reach the optimum value reduced significantly.

scholarly journals Geochemical characterization and assessment of fluoride sources in groundwater of Siloam area, Limpopo Province, South Africa

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tobiloba Onipe ◽  
Joshua N. Edokpayi ◽  
John O. Odiyo
Keyword(s):  
Dental Fluorosis ◽  
Fluoride Concentration ◽  
Limpopo Province ◽  
Water Type ◽  
X Ray Diffraction ◽  
Kaolinite Clay ◽  
X Ray ◽  
High Incidence ◽  
High Fluoride ◽  
Fluoride Ion Selective Electrode

AbstractSiloam’s groundwater is reportedly characterized by high fluoride. In response to the reported high incidence of dental fluorosis in the area, sources of elevated fluoride in the groundwater were investigated. Total fluoride (TF) was determined using Ion Chromatograph and Fluoride Ion Selective Electrode. The mineral composition of rocks and soils were determined using X-ray Fluorescence and X-ray diffraction, respectively. Results revealed that groundwater fluoride concentration ranged from 3.92 to 4.95 mg/L. Na-Cl water type was found to be dominant in the water samples. TF content of the rocks and soils ranged from 10 to 2000 mg/L. Leachates were obtained by making a slurry from the samples at a predetermined temperature and time. TF in leachates ranged between 0.27 and 14.88 mg/L and 0.05 to 10.40 mg/L at induced, and non-induced temperatures, respectively. The possible source of fluoride has been previously inferred to be caused by fluorite minerals occurring at greater depth. However, this study proves that fluoride decreases with depth and the elevated fluoride in the groundwater is caused by smectite-kaolinite clay, muscovite and chlorite minerals abundant in the area. Geothermal temperature exhibited by the groundwater in the area is a major factor enhancing the release of fluoride from the clay materials.

The Paradox of (De)politicisation in a Selected South African Municipality: An Afrocentric Ethical Reflection

Politeia ◽  
2019 ◽  
Vol 38 (2) ◽  
Author(s):  
Kgothatso B. Shai
Keyword(s):  
South Africa ◽  
Local Government ◽  
Rural Areas ◽  
Urban Areas ◽  
Local Governance ◽  
African National Congress ◽  
Limpopo Province ◽  
African Culture ◽  
Government Administration ◽  
Traditional Leadership

South Africa’s local government administration is complex in that both traditional leadership and elected municipal councils play a role in it. Traditional leadership occupies an essential position and status in local government administration, in particular in rural South Africa. However, the contemporary administrative jurisdiction of municipalities cuts across both rural and urban areas. In the rural areas, the conflict over the division of roles between traditional leaders and elected councillors is evident. Due to the influence and dominance of the neo-liberal global order, modernists often accuse traditional leadership of being undemocratic and authoritarian. However, the reality is that elected councils’ administration also leaves much to be desired, and the consequences of their poor administration are not uniformly understood. Since South Africa is a democratic state, it is expected that there should be a clear separation in government institutions between party (i.e., the ruling African National Congress) politics and public administration; a phenomenon that some describe as depoliticisation. Nevertheless, the realities on the ground suggest otherwise. This article, which is based on the theory of Afrocentricity, examines a selected rural municipality (Maruleng) in South Africa’s Limpopo province to critically reflect on the ethics and the value system of African culture in the context of local governance vis-à-vis Westernised governance principles. The aim of this research is achieved through interdisciplinary critical discourse and thematic analysis in its broadest form.

scholarly journals Removal of Fluoride from Drinking Water by Sorption Using Diatomite Modified with Aluminum Hydroxide

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Tesfaye Akafu ◽  
Achalu Chimdi ◽  
Kefyalew Gomoro
Keyword(s):  
Aluminum Hydroxide ◽  
Contact Time ◽  
Fluoride Concentration ◽  
Freundlich Isotherm ◽  
Intraparticle Diffusion ◽  
Fluoride Removal ◽  
Contaminated Water ◽  
Optimum Conditions ◽  
Intraparticle Diffusion Model ◽  
Adsorbent Dose

Exposure to fluoride beyond the recommended level for longer duration causes both dental and skeletal fluorosis. Thus, the development of cost-effective, locally available, and environmentally benign adsorbents for fluoride removal from contaminated water sources is absolutely required. In the present study, diatomaceous earth (diatomite) locally available in Ethiopia, modified by treating it with an aluminum hydroxide solution, was used as an adsorbent for fluoride removal from aqueous solutions. Adsorption experiments were carried out by using batch contact method. The adsorbent was characterized using FT-IR spectroscopy. Effects of different parameters affecting efficiency of fluoride removal such as adsorbent dose, contact time, initial fluoride concentration, and pH were investigated and optimized. The optimum adsorbent dose, contact time, initial fluoride concentration, and pH values were 25 g/L, 180 min, 10 mg/L, and 6.7, respectively. The performance of the adsorbent was also tested under optimum conditions using groundwater samples taken from Hawassa and Ziway. Langmuir and Freundlich isotherm models were applied to describe the equilibrium data. Compared to Langmuir isotherm (R2 = 0.888), the Freundlich isotherm (R2 = 0.985) model was better fitted to describe the adsorption characteristics of fluoride on Al-diatomite. The Langmuir maximum adsorption capacity was 1.67 mg/g. The pseudosecond-order model was found to be more suitable than the pseudofirst-order to describe the adsorption kinetics. The low correlation coefficient value of R2 = 0.596 for the intraparticle diffusion model indicates that the intraparticle diffusion model does not apply to the present studied adsorption system. The maximum fluoride removal was observed to be 89.4% under the optimum conditions which indicated that aluminum hydroxide-modified diatomite can be used as efficient, cheap, and ecofriendly adsorbents for the removal of fluoride from contaminated water.

scholarly journals Spectroscopic Determination of Water Salinity in Brackish Surface Water in Nandoni Dam, at Vhembe District, Limpopo Province, South Africa

Water ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 990 ◽  
Author(s):  
Lebea Nthunya ◽  
Sebabatso Maifadi ◽  
Bhekie Mamba ◽  
Arne Verliefde ◽  
Sabelo Mhlanga
Keyword(s):  
South Africa ◽  
Water Supply ◽  
Water Samples ◽  
Water Resource Management ◽  
Treatment Plant ◽  
Limpopo Province ◽  
World Health ◽  
Water Salinity ◽  
Vhembe District ◽  
Dissolved Salts

The problem of limited water supply in the Vhembe District (Limpopo Province, South Africa) is exacerbated by a preponderance of dissolved salts, which cause disagreeable taste and odour in the water as reported by the communities using this water for drinking. The water treatment plant that supplies the treated water to the communities in the District sources this raw water from the Nandoni Dam at the Luvuvhu river catchment. There are no scientific studies that have been reported in the literature that focused on determining the levels of water salinity from various water sources in the municipalities of the District. Water samples from various sites across the Nandoni Dam, a primary source of domestic water supply in the region, were collected through each season over a period of twelve months in order to ascertain the concentrations of dissolved salts in the dam. Onsite analyses of the water samples were conducted using the YSI ProDSS multimeter, while the laboratory water analyses were conducted using the spectroquant and atomic absorption spectrometers. Although salinity tests seem to indicate that the water sampled across most of the Nandoni Dam is brackish during all seasons of the year with the highest being 750 mg/L, water samples from the dam mid-outlet and the treatment plant are slightly below the World Health Organization (WHO) brackish water bracket of 500 mg/L with unfavourable taste for drinking. Results from this study indicate that the water sourced from the Nandoni Dam is not suitable for human consumption and therefore requires integrated water resource management, as well as robust and cost-effective water desalination treatment.

scholarly journals Factors influencing treatment outcomes in tuberculosis patients in Limpopo Province, South Africa, from 2006 to 2010: A retrospective study

Curationis ◽  
2014 ◽  
Vol 37 (1) ◽  
Author(s):  
Mohammed M. Gafar ◽  
Norman Z. Nyazema ◽  
Yoswa M. Dambisya
Keyword(s):  
South Africa ◽  
Treatment Outcomes ◽  
Health Facility ◽  
Treatment Regimen ◽  
Diagnostic Category ◽  
Limpopo Province ◽  
World Health ◽  
Factors Influencing ◽  
Health Facility Level ◽  
Facility Level

Background: South Africa has a high burden of tuberculosis (TB), with high human immunodeficiency virus (HIV)-TB co-infection rates and the emergence of multidrugresistant TB.Objectives: To describe treatment outcomes and factors influencing outcomes amongst pulmonary TB (PTB) patients in the Limpopo Province.Method: A retrospective review was conducted of data on the provincial electronic TB register (ETR.net) for the years 2006 to 2010 (inclusive), and a random sample of 1200 records was selected for further analysis. The Chi square test was used to examine the influence of age, gender, health facility level, diagnostic category and treatment regimen on treatment outcomes.Results: Overall 90 617 (54.6% male) PTB patients were registered between 2006 and 2010. Of the sampled 1200 TB cases, 72.6% were in persons aged 22 to 55 years and 86.2% were new cases. The TB mortality rate was 13.6% (much higher than the World Health Organization target of 3%), whilst the default rate was 9.8%. There was a strong association between age (P < 0.001), diagnostic category (P < 0.001), treatment regimen (P < 0.001), and health facility level (P < 0.001) and treatment outcome. Those aged 22–55, and 56–74 years were more likely to die (P < 0.05). Poor treatment outcomes were also associated with initial treatment failure, receiving treatment at hospital and treatment regimen II.Conclusion: The poor TB treatment outcomes in Limpopo, characterised by a high mortality and default rates, call for strengthening of the TB control programme, which should include integration of HIV and/or AIDS and TB services. 

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