Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp

The presence of fluoride ions in water poses a significant danger to human health. In Tanzania, where the Rift Valley passes, some people are impaired due to elevated levels of fluoride in water. The purpose of this study was to prepare thermally activated Adansonia digitata fruit pericarp biosorben...

Full description

Bibliographic Details
Main Authors: David Mihayo, Maheswara Rao Vegi, Said Ali Hamad Vuai
Format: Article
Language:English
Published: SAGE Publishing 2021-01-01
Series:Adsorption Science & Technology
Online Access:http://dx.doi.org/10.1155/2021/5574900
_version_ 1826902967500931072
author David Mihayo
Maheswara Rao Vegi
Said Ali Hamad Vuai
author_facet David Mihayo
Maheswara Rao Vegi
Said Ali Hamad Vuai
author_sort David Mihayo
collection DOAJ
description The presence of fluoride ions in water poses a significant danger to human health. In Tanzania, where the Rift Valley passes, some people are impaired due to elevated levels of fluoride in water. The purpose of this study was to prepare thermally activated Adansonia digitata fruit pericarp biosorbents at 450, 500, 550, and 600°C for defluoridation. Using the Brunauer-Emmett-Teller analyzer, the surface area and pore diameter were measured. The scanning electron microscope and Fourier transform infrared spectrometry were used to determine morphological features and functional groups of biosorbents. To analyze the effect of pH, adsorbent dose, contact time, and initial concentration, the response surface methodology was applied. Adsorption isotherms, kinetics, and regeneration studies were also conducted. There were considerably wide surface areas of 385.44, 399.27, 445.71, and 447.70 m2/g and pore diameters of 0.3055, 3.0341, 3.0375, and 3.0471 nm for biosorbents activated at 450, 500, 550, and 600°C, respectively. FT-IR spectra indicated the oxidation of alcoholic –OH to carboxylic –OH during the activation process, which is proved by the shifting of the peak at 3500-3000 cm-1 from raw biosorbent to a very broad and strong band at 3500-2000 cm-1 from the activated biosorbent. The maximum removal efficiencies of biosorbents activated at 450, 500, 550, and 600°C were 95.55, 96.50, 97.65, and 98.36%, respectively, for all biosorbents at a pH of 2, an initial concentration of 27.50 ppm, a contact period of 75.00 minutes, and an adsorbent dose of 5.50 g, which indicates that the adsorbents were successful for fluoride removal. The isotherms and kinetics indicated that the adsorption fitted well with Freundlich (R2=0.95661‐0.98445) and pseudo-second-order (R2=0.94230‐0.99634) kinetic adsorption models, respectively. The results showed that the removal of fluoride by biosorbents prepared is effective and could be used for defluoridation of drinking water.
first_indexed 2024-03-07T18:02:20Z
format Article
id doaj.art-18cb93fa0e714ff89ecb1c61f06e4d14
institution Directory Open Access Journal
issn 0263-6174
2048-4038
language English
last_indexed 2025-02-17T07:47:43Z
publishDate 2021-01-01
publisher SAGE Publishing
record_format Article
series Adsorption Science & Technology
spelling doaj.art-18cb93fa0e714ff89ecb1c61f06e4d142025-01-03T01:22:56ZengSAGE PublishingAdsorption Science & Technology0263-61742048-40382021-01-01202110.1155/2021/55749005574900Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit PericarpDavid Mihayo0Maheswara Rao Vegi1Said Ali Hamad Vuai2The Department of Chemistry, College of Natural and Mathematical Sciences, The University of Dodoma, Dodoma, P.O. Box 259, TanzaniaThe Department of Chemistry, College of Natural and Mathematical Sciences, The University of Dodoma, Dodoma, P.O. Box 259, TanzaniaThe Department of Chemistry, College of Natural and Mathematical Sciences, The University of Dodoma, Dodoma, P.O. Box 259, TanzaniaThe presence of fluoride ions in water poses a significant danger to human health. In Tanzania, where the Rift Valley passes, some people are impaired due to elevated levels of fluoride in water. The purpose of this study was to prepare thermally activated Adansonia digitata fruit pericarp biosorbents at 450, 500, 550, and 600°C for defluoridation. Using the Brunauer-Emmett-Teller analyzer, the surface area and pore diameter were measured. The scanning electron microscope and Fourier transform infrared spectrometry were used to determine morphological features and functional groups of biosorbents. To analyze the effect of pH, adsorbent dose, contact time, and initial concentration, the response surface methodology was applied. Adsorption isotherms, kinetics, and regeneration studies were also conducted. There were considerably wide surface areas of 385.44, 399.27, 445.71, and 447.70 m2/g and pore diameters of 0.3055, 3.0341, 3.0375, and 3.0471 nm for biosorbents activated at 450, 500, 550, and 600°C, respectively. FT-IR spectra indicated the oxidation of alcoholic –OH to carboxylic –OH during the activation process, which is proved by the shifting of the peak at 3500-3000 cm-1 from raw biosorbent to a very broad and strong band at 3500-2000 cm-1 from the activated biosorbent. The maximum removal efficiencies of biosorbents activated at 450, 500, 550, and 600°C were 95.55, 96.50, 97.65, and 98.36%, respectively, for all biosorbents at a pH of 2, an initial concentration of 27.50 ppm, a contact period of 75.00 minutes, and an adsorbent dose of 5.50 g, which indicates that the adsorbents were successful for fluoride removal. The isotherms and kinetics indicated that the adsorption fitted well with Freundlich (R2=0.95661‐0.98445) and pseudo-second-order (R2=0.94230‐0.99634) kinetic adsorption models, respectively. The results showed that the removal of fluoride by biosorbents prepared is effective and could be used for defluoridation of drinking water.http://dx.doi.org/10.1155/2021/5574900
spellingShingle David Mihayo
Maheswara Rao Vegi
Said Ali Hamad Vuai
Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp
Adsorption Science & Technology
title Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp
title_full Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp
title_fullStr Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp
title_full_unstemmed Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp
title_short Defluoridation of Aqueous Solution Using Thermally Activated Biosorbents Prepared from Adansonia digitata Fruit Pericarp
title_sort defluoridation of aqueous solution using thermally activated biosorbents prepared from adansonia digitata fruit pericarp
url http://dx.doi.org/10.1155/2021/5574900
work_keys_str_mv AT davidmihayo defluoridationofaqueoussolutionusingthermallyactivatedbiosorbentspreparedfromadansoniadigitatafruitpericarp
AT maheswararaovegi defluoridationofaqueoussolutionusingthermallyactivatedbiosorbentspreparedfromadansoniadigitatafruitpericarp
AT saidalihamadvuai defluoridationofaqueoussolutionusingthermallyactivatedbiosorbentspreparedfromadansoniadigitatafruitpericarp