Ragiab Iss - Profile on Academia.edu (original) (raw)

Papers by Ragiab Iss

Mağallaẗ al-ʿulūm al-baḥṯaẗ wa-al-taṭbīqiyyaẗ, Apr 15, 2024

This work is based on the investigation of uranyl (VI) ion adsorption onto natural diatomite usin... more This work is based on the investigation of uranyl (VI) ion adsorption onto natural diatomite using batch sorption method under different parameters such as pH, initial ion concentration, adsorbent amount and effect of sulfate ion as a foreign ion. 8-hydroxyquinoline is used as a chromogen forming a pale-yellow complex with 𝑈𝑂 2 2+ ions in chloroform, the absorbance was measured spectrophotometrically at λmax 460 nm, obtaining a linear calibration curve with R 2 =0.998, LOD=3.03 mg/L and LOQ=9.21 mg/L. Prior to the implementation of the batch experiment, the morphology and composition of diatomite was confirmed using XRF (Bruker S8 Tiger), XRD (Bruker D5005), FTIR (Bruker Vector 22), and SEM (JEOL JSM-5610 LV) techniques. From spectrophotometric analysis, the results showed that the maximum uranyl ion adsorption distribution coefficient reached at the initial concentration of 50ppm, pH 4.5, contact time 5hrs and adsorption dosage of 2 g/L. There was no significant effect of sulfate ion on the adsorption affinity. Adsorption isotherm was studied by Langmuir which was favourable model fitting with R 2 =0.996 and maximum adsorption capacity of 16mg/g, and separation factor RL = 0.0122. Freundlich isotherm model also applied for the same data and give a very straight line with R 2 = 1.00 and maximum adsorption capacity of 200 mg/g. Temkin model was less fit and gave a negative isotherm curve with R 2 = 0.78, KT= 0.9405 L/g, bT= 24.724 J/mol. Langmuir and Freundlich isotherms gave exothermic adsorption while Temkin gave an endothermic one.

The Use of Fourier-Transform Infrared Spectroscopy to Assess Libyan Virgin Olive Oil Adulteration with Corn and Sun Flower Oils

Academic journal of chemistry, 2018

[Thesis]. Manchester, UK: The University of Manchester; 2013., Mar 12, 2013

Dedication Acknowledgement Chapter 1: Introduction 1. Clay and clay minerals 7.3.1.2 HA>100 kDa f... more Dedication Acknowledgement Chapter 1: Introduction 1. Clay and clay minerals 7.3.1.2 HA>100 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model fit, humic acids at 0, 10, 20, 50 and 100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.1.3 100>HA>10 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0, 10, 20, 50 and 100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.1.4 10>HA>3 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.1.5 HA<3 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.2.1 unfractionated HA (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.1 M NaClO 4 7.3.2.2 HA>100 k Da (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.1 M NaClO 4 7.3.2.3 100>HA>10 k Da (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.1 M NaClO 4 7.3.2.4 10>HA>3 k Da (a) and Eu (III) ions (b) sorption on montmorillonite, 3.3.1 Chemical composition of montmorillonite 3.3.2 Chemical composition of raw bentonite 3.3.3 Chemical composition of raw diatomite 3.3.4 Chemical composition of kaolinite samples 3.6.1 The surface area values for the minerals from BET method 3.8.1 The CEC capacities for different particle size kaolinite and bentonite Chapter 4: 4.2.3.1 HA percentages sorbed and Kd values as the adsorbent is renewed Chapter 5: 5.1.2 The Sorbed % change of Eu 3+ as a function of HA concentration Chapter 6: 6.1.5.1 the linear equation for the sorption isotherm and R 2 for some metal ions on montmorillonite 6.2.4.1 the linear equation and R 2 values for the metal ion sorption isotherm on the kaolinite samples Chapter 7: 7.1 Equations for models 1 and 2 7.2 Equations for model 3 Appendix A: A.4.1.1 Data for the calculation of Kd values of humic acid sorption onto

Sorption of humic acid and europium onto montmorillonite as a function of pH, ionic strength and metal ion concentration

Mineralogical Magazine, Nov 1, 2015

Ternary systems of 152 Eu(III), bulk bentonite and ethylenediaminetetraacetic acid (EDTA) ([Eu] =... more Ternary systems of 152 Eu(III), bulk bentonite and ethylenediaminetetraacetic acid (EDTA) ([Eu] = 7.9 × 10 −10 M; pH = 6.0-7.0) have been studied. Without EDTA, there was slow uptake in a two-stage process, with initial rapid sorption of Eu(III) (96%), followed by slower uptake of a much smaller fraction (3.0% over a period of one month). The reversibility of Eu(III) binding was tested by allowing Eu(III) to sorb to bentonite for 1-322 days. EDTA was added to the pre-equilibrated Eu bentonite systems at 0.01 M, a concentration that was sufficient to suppress sorption in a system where EDTA was present prior to the contact of Eu(III) with bentonite. A fraction of the Eu was released instantaneously (30-50%), but a significant amount remained bound. With time, the amount of Eu(III) retained by the bentonite reduced, with a slow fraction dissociation rate constant of approximately 4.3 × 10 −8 s −1 (values in the range 2.2 × 10 −8-1.0 × 10 −7 s −1) for pre-equilibration times ≥7 days. Eventually, the amount of Eu(III) remaining bound to the bentonite was within error of that when EDTA was present prior to contact (4.5% ± 0.6), although in systems with pre-equilibration times >100 days, full release took up to 500 days. Europium interactions with colloidal bentonite were also studied, and the dissociation rate constant measured by a resin competition method. For the colloids, more Eu was found in the slowly dissociating fraction (60-70%), but the first-order dissociation rate constant was faster, with an average rate constant of 8.8 × 10 −7 s −1 and a range of 7.7 × 10 −7-9.5 × 10 −7 s −1. For both bulk and colloidal bentonite, although slow dissociation was observed for Eu(III), there was no convincing evidence for 'irreversible' binding.

Removal of uranium (VI) ion from aqueous solution using kaolinite

Kuwait Journal of Science

Academic journal of chemistry, Dec 6, 2022

Chlorine disinfection is a commonly applied disinfection products due to its effectiveness, stron... more Chlorine disinfection is a commonly applied disinfection products due to its effectiveness, strong disinfection ability and low cost. The objective of this study is to investigate the occurrence of haloacetic acids (HAAs), a group of disinfection byproducts, in swimming pool and spa water, and analyze its influencing factors, so as to provide reference to understand the pollution status of haloacetic acid (HAAs) disinfection byproducts in swimming pool water in Haikou, for the formulation of hygienic standards and sanitation management of HAAs in swimming pool water. The samples were collected from18 swimming places with sanitary licenses in Haikou. For a period from April to July in 2022. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS) was used to detect the concentration of HAAs in swimming pool water, and its influencing factors were also analyzed.. Results indicated that the levels of average concentration of HAAs in indoor and outdoor swimming pools were 176.20 μg•L-1 and 241.53 μg•L-1 , respectively. There were differences in the levels of HAAs in indoor and outdoor swimming places (p<0.05). The Pearson correlation analysis showed that the concentration of HAAs was positively correlated with free chlorine and urea (p<0.05). The water quality and sanitation of the swimming pools in this survey were somewhat poor. It is necessary to formulate the regulation of HAAs in the swimming pool sanitation standards, and strengthen the water quality sanitation management, and take further effective measures to reduce the concentration of HAAs to protect swimmers.

Thirteen Olive oil samples were collected from five different places in the western Libyan region... more Thirteen Olive oil samples were collected from five different places in the western Libyan region with different cultivation periods. The physical and chemical properties of samples were investigated and classified whether they comply with the Libyan standard specification number 8/2002 or not. The density and refractive index of almost all samples were found within the normal range (0.908-0.919) and (1.4688-1.4705) respectively whereas the chemical properties showed a range of fluctuated values such as peroxide number (11.20-60.40), acidity value (0.737-17.94), saponification number (185.34-199.65), esterification number (173.84-194.36) and iodine number (71.00-94.10). A third of the investigated samples are considered to be of good quality mainly the newer samples

The Use of Fourier-Transform Infrared Spectroscopy to Assess Libyan Virgin Olive Oil Adulteration with Corn and Sun Flower Oils

Modern improvements in Fourier transform infrared spectroscopy instrumentation spread out the app... more Modern improvements in Fourier transform infrared spectroscopy instrumentation spread out the application of this technique to the field of food research. This study is focused to evaluate the efficiency of FT-IR spectroscopy in order to assess the Libyan virgin olive oil adulteration with cheaper vegetable oils: sunflower oil and corn oil. Taking a closer inspection to different regions of recorded IR spectra of both pure oil sample (virgin olive oil, sun flower oil, corn oil) and their mixture: It is noticed that an absorbance shift was identified at about 3000 cm-1 due to the C-H stretching vibration of the cis-double bond proved to be reliable index for assessing of virgin olive oil adulteration by vegetable oil addition. Also, the absorbance at about 3008 cm-1, characteristic to the oils with a high saturated fatty acids content and short carbohydrate chain, recorded appreciable changes by increasing of vegetable oil percent added in virgin olive oil. Based on the calibration c...

Mağallaẗ al-ʿulūm al-baḥṯaẗ wa-al-taṭbīqiyyaẗ, Apr 15, 2024

This work is based on the investigation of uranyl (VI) ion adsorption onto natural diatomite usin... more This work is based on the investigation of uranyl (VI) ion adsorption onto natural diatomite using batch sorption method under different parameters such as pH, initial ion concentration, adsorbent amount and effect of sulfate ion as a foreign ion. 8-hydroxyquinoline is used as a chromogen forming a pale-yellow complex with 𝑈𝑂 2 2+ ions in chloroform, the absorbance was measured spectrophotometrically at λmax 460 nm, obtaining a linear calibration curve with R 2 =0.998, LOD=3.03 mg/L and LOQ=9.21 mg/L. Prior to the implementation of the batch experiment, the morphology and composition of diatomite was confirmed using XRF (Bruker S8 Tiger), XRD (Bruker D5005), FTIR (Bruker Vector 22), and SEM (JEOL JSM-5610 LV) techniques. From spectrophotometric analysis, the results showed that the maximum uranyl ion adsorption distribution coefficient reached at the initial concentration of 50ppm, pH 4.5, contact time 5hrs and adsorption dosage of 2 g/L. There was no significant effect of sulfate ion on the adsorption affinity. Adsorption isotherm was studied by Langmuir which was favourable model fitting with R 2 =0.996 and maximum adsorption capacity of 16mg/g, and separation factor RL = 0.0122. Freundlich isotherm model also applied for the same data and give a very straight line with R 2 = 1.00 and maximum adsorption capacity of 200 mg/g. Temkin model was less fit and gave a negative isotherm curve with R 2 = 0.78, KT= 0.9405 L/g, bT= 24.724 J/mol. Langmuir and Freundlich isotherms gave exothermic adsorption while Temkin gave an endothermic one.

The Use of Fourier-Transform Infrared Spectroscopy to Assess Libyan Virgin Olive Oil Adulteration with Corn and Sun Flower Oils

Academic journal of chemistry, 2018

[Thesis]. Manchester, UK: The University of Manchester; 2013., Mar 12, 2013

Dedication Acknowledgement Chapter 1: Introduction 1. Clay and clay minerals 7.3.1.2 HA>100 kDa f... more Dedication Acknowledgement Chapter 1: Introduction 1. Clay and clay minerals 7.3.1.2 HA>100 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model fit, humic acids at 0, 10, 20, 50 and 100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.1.3 100>HA>10 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0, 10, 20, 50 and 100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.1.4 10>HA>3 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.1.5 HA<3 kDa fraction (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.01 M NaClO 4 7.3.2.1 unfractionated HA (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.1 M NaClO 4 7.3.2.2 HA>100 k Da (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.1 M NaClO 4 7.3.2.3 100>HA>10 k Da (a) and Eu (III) ions (b) sorption on montmorillonite, experimental and model 3 fit, humic acids at 0-100 ppm in both cases. The pH = 6.0  0.1 and the solid to solution ratio is 0.05 g montmorillonite to 10 ml electrolyte solution, and I = 0.1 M NaClO 4 7.3.2.4 10>HA>3 k Da (a) and Eu (III) ions (b) sorption on montmorillonite, 3.3.1 Chemical composition of montmorillonite 3.3.2 Chemical composition of raw bentonite 3.3.3 Chemical composition of raw diatomite 3.3.4 Chemical composition of kaolinite samples 3.6.1 The surface area values for the minerals from BET method 3.8.1 The CEC capacities for different particle size kaolinite and bentonite Chapter 4: 4.2.3.1 HA percentages sorbed and Kd values as the adsorbent is renewed Chapter 5: 5.1.2 The Sorbed % change of Eu 3+ as a function of HA concentration Chapter 6: 6.1.5.1 the linear equation for the sorption isotherm and R 2 for some metal ions on montmorillonite 6.2.4.1 the linear equation and R 2 values for the metal ion sorption isotherm on the kaolinite samples Chapter 7: 7.1 Equations for models 1 and 2 7.2 Equations for model 3 Appendix A: A.4.1.1 Data for the calculation of Kd values of humic acid sorption onto

Sorption of humic acid and europium onto montmorillonite as a function of pH, ionic strength and metal ion concentration

Mineralogical Magazine, Nov 1, 2015

Ternary systems of 152 Eu(III), bulk bentonite and ethylenediaminetetraacetic acid (EDTA) ([Eu] =... more Ternary systems of 152 Eu(III), bulk bentonite and ethylenediaminetetraacetic acid (EDTA) ([Eu] = 7.9 × 10 −10 M; pH = 6.0-7.0) have been studied. Without EDTA, there was slow uptake in a two-stage process, with initial rapid sorption of Eu(III) (96%), followed by slower uptake of a much smaller fraction (3.0% over a period of one month). The reversibility of Eu(III) binding was tested by allowing Eu(III) to sorb to bentonite for 1-322 days. EDTA was added to the pre-equilibrated Eu bentonite systems at 0.01 M, a concentration that was sufficient to suppress sorption in a system where EDTA was present prior to the contact of Eu(III) with bentonite. A fraction of the Eu was released instantaneously (30-50%), but a significant amount remained bound. With time, the amount of Eu(III) retained by the bentonite reduced, with a slow fraction dissociation rate constant of approximately 4.3 × 10 −8 s −1 (values in the range 2.2 × 10 −8-1.0 × 10 −7 s −1) for pre-equilibration times ≥7 days. Eventually, the amount of Eu(III) remaining bound to the bentonite was within error of that when EDTA was present prior to contact (4.5% ± 0.6), although in systems with pre-equilibration times >100 days, full release took up to 500 days. Europium interactions with colloidal bentonite were also studied, and the dissociation rate constant measured by a resin competition method. For the colloids, more Eu was found in the slowly dissociating fraction (60-70%), but the first-order dissociation rate constant was faster, with an average rate constant of 8.8 × 10 −7 s −1 and a range of 7.7 × 10 −7-9.5 × 10 −7 s −1. For both bulk and colloidal bentonite, although slow dissociation was observed for Eu(III), there was no convincing evidence for 'irreversible' binding.

Removal of uranium (VI) ion from aqueous solution using kaolinite

Kuwait Journal of Science

Academic journal of chemistry, Dec 6, 2022

Chlorine disinfection is a commonly applied disinfection products due to its effectiveness, stron... more Chlorine disinfection is a commonly applied disinfection products due to its effectiveness, strong disinfection ability and low cost. The objective of this study is to investigate the occurrence of haloacetic acids (HAAs), a group of disinfection byproducts, in swimming pool and spa water, and analyze its influencing factors, so as to provide reference to understand the pollution status of haloacetic acid (HAAs) disinfection byproducts in swimming pool water in Haikou, for the formulation of hygienic standards and sanitation management of HAAs in swimming pool water. The samples were collected from18 swimming places with sanitary licenses in Haikou. For a period from April to July in 2022. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS) was used to detect the concentration of HAAs in swimming pool water, and its influencing factors were also analyzed.. Results indicated that the levels of average concentration of HAAs in indoor and outdoor swimming pools were 176.20 μg•L-1 and 241.53 μg•L-1 , respectively. There were differences in the levels of HAAs in indoor and outdoor swimming places (p<0.05). The Pearson correlation analysis showed that the concentration of HAAs was positively correlated with free chlorine and urea (p<0.05). The water quality and sanitation of the swimming pools in this survey were somewhat poor. It is necessary to formulate the regulation of HAAs in the swimming pool sanitation standards, and strengthen the water quality sanitation management, and take further effective measures to reduce the concentration of HAAs to protect swimmers.

Thirteen Olive oil samples were collected from five different places in the western Libyan region... more Thirteen Olive oil samples were collected from five different places in the western Libyan region with different cultivation periods. The physical and chemical properties of samples were investigated and classified whether they comply with the Libyan standard specification number 8/2002 or not. The density and refractive index of almost all samples were found within the normal range (0.908-0.919) and (1.4688-1.4705) respectively whereas the chemical properties showed a range of fluctuated values such as peroxide number (11.20-60.40), acidity value (0.737-17.94), saponification number (185.34-199.65), esterification number (173.84-194.36) and iodine number (71.00-94.10). A third of the investigated samples are considered to be of good quality mainly the newer samples

The Use of Fourier-Transform Infrared Spectroscopy to Assess Libyan Virgin Olive Oil Adulteration with Corn and Sun Flower Oils

Modern improvements in Fourier transform infrared spectroscopy instrumentation spread out the app... more Modern improvements in Fourier transform infrared spectroscopy instrumentation spread out the application of this technique to the field of food research. This study is focused to evaluate the efficiency of FT-IR spectroscopy in order to assess the Libyan virgin olive oil adulteration with cheaper vegetable oils: sunflower oil and corn oil. Taking a closer inspection to different regions of recorded IR spectra of both pure oil sample (virgin olive oil, sun flower oil, corn oil) and their mixture: It is noticed that an absorbance shift was identified at about 3000 cm-1 due to the C-H stretching vibration of the cis-double bond proved to be reliable index for assessing of virgin olive oil adulteration by vegetable oil addition. Also, the absorbance at about 3008 cm-1, characteristic to the oils with a high saturated fatty acids content and short carbohydrate chain, recorded appreciable changes by increasing of vegetable oil percent added in virgin olive oil. Based on the calibration c...