In Jordan, large amounts of fly ash (FA) are produced from heavy fuel composition in power statio... more In Jordan, large amounts of fly ash (FA) are produced from heavy fuel composition in power stations. The produced fly ash is highly contaminated with heavy metals including V, Ni, Zn and Fe. Geopolymer containing different amounts of FA was fabricated for sake of minimising the mobility of toxic elements in the repository site. Using local kaolinite, fly ash and NaOH mixture, five geopolymers were prepared at room temperature and cured at 80 o C at the following ratios: Si/Al: 1.68-4.71, Na 2 O/Al 2 O 3 : 1.48-1.84, Na/Al: 0.74-0.92. The maximum compressive strength was observed for the geopolymer containing no fly ash, 28 Mpa at day 1 and dry sample. A geopolymer containing 10% FA showed promising results where a compressive strength of 23 Mpa was reported. The porosity of FA has been partially destroyed after polymerisation process as indicated from SEM pictures and XRD analysis; new phases have been created under the action of applied pressure. The leachability test indicated that the samples of higher FA are more leachable. The results proved that involving FA in geopolymerisation was significantly decreased the mobility of the toxic metals like Ni and V. Therefore, the prepared geopolymers will definitely have important industrial applications.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 2012
ABSTRACT A complex, impact structure was recently discovered at Jebel Waqf as Suwwan, in the cent... more ABSTRACT A complex, impact structure was recently discovered at Jebel Waqf as Suwwan, in the central part of the eastern region of Jordan. Shatter cones and cataclasis of sandstone and limestone from the outer side of the inner central uplift area confirm the impact origin of the Waqf as Suwwan structure. Cataclased and deformed chert fragments, nodules and concretions from the surface regolith layer of the outer inner ring were investigated. The microstructures of the collected samples were investigated using XRD (X-ray diffraction), XRF (X-ray Fluorescence) and ESM-EDX (energy Dispersive X-ray analysis) techniques. Brecciation, dislocation, recrystallization processes, and subplanar jointing and fractures of the chert are among the most important aspects. Additionally, feather features are common planar microstructures in the quartzite breccia. Some of the observations have previously been interpreted as sedimentary features, but since Waqf as Suwwan represents a confirmed impact structure, it is debatable as to whether some of the observed deformation effects are the result of the impact event.
This paper reports an investigation of the oxidation state of Cr in samples of natural céments fo... more This paper reports an investigation of the oxidation state of Cr in samples of natural céments formed 500 ky
The adsorption of lead [Pb(II)] ions onto adsorbents prepared by alkali solid-state conversion of... more The adsorption of lead [Pb(II)] ions onto adsorbents prepared by alkali solid-state conversion of kaolin and natural zeolite mixture was investigated. The adsorption isotherms were obtained and the Langmuir parameters were calculated in order to make a comparison between the adsorption capacities of synthesized adsorbents and those of their constituents. The synthesized adsorbents exhibit much higher adsorption capacity than kaolin and zeolite. Therefore, the low-cost adsorbent based on kaolin and Jordanian zeolite has important features since it has an extraordinary adsorption capacity towards Pb(II) ions (157 mg Pb(II)/g at pH 6.0 and 0.1 M ionic strength). Furthermore, the results implied the advantage of using zeolite as filler in kaolin-based geopolymers and the advantage of using kaolin as a binder for zeolite in their use as industrial adsorbents in water purification. The adsorption capacity of the synthesized adsorbents, unexpectedly, increases with pH decrease and ionic strength increase. The XRD pattern of the synthesized adsorbent prepared from Jordanian kaolin (JK) and zeolite indicates that it is amorphous.
A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to produce l... more A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to produce low environmental impact materials from local raw materials. In this paper the emphasis is on the general characteristics of the material and on its durability. With the used kaolinite, specimens with compressive strength of 41 MPa under dry conditions and 23 MPa under immersed water conditions were obtained. The durability under environmental conditions was good.
The present review of high- and low-temperature minerals demonstrates the value of the pyrometamo... more The present review of high- and low-temperature minerals demonstrates the value of the pyrometamorphic rocks, altered varicolored marble (cement zones), travertine, and regolith in Jordan as analogues of cementitious repositories. The alkaline leachate contains hazardous elements such as Zn, Cd, Fe, Ni, Cu, V, Cr, Fe, Mo, As, Co, U, etc. The sites offer a good chance to investigate the interaction of the circulating high alkaline water with the rocks. The unusual high- and low-temperature minerals proved to be durable elements immobilizers which act as sinks for hazardous trace elements. The identified minerals and the solid solution series are indicators of the long-term behavior of natural analogues of cement-dominated repositories.
Unlike coal fly ash, fly ash of heavy fuel oil has received much less attention in the literature... more Unlike coal fly ash, fly ash of heavy fuel oil has received much less attention in the literature. In this work, detailed physicochemical characterization of heavy fuel oil fly ash (FA) is provided. The ash has a carbonaceous matrix and contains V, Ni, Zn, Cr, Cu, and Pb with variable amounts. V was the most abundant heavy metal with enrichment factor of 277 in the FA. The presence of V in the FA is attributed to the formation of Mg 3 V 2 O 8 oxides at high combustion temperature as confirmed by XRD. Particle size distribution showed that the mean particle diameter of the FA was 70.5 μm. Extraction recovery up to 85% of metals was achieved using 1.0 M HNO 3 and at room temperature. Standard metal-leaching tests confirmed that the elution of the toxic metals and the level of eluted Zn were much higher than the regulated value for the solid residues. Five stable geopolymers GPs containing 41.7 wt.% FA were prepared. All GPs showed high compressive strength and low water absorption which support their application as lightweight construction composites. Most importantly, adding FA to GP had significantly reduced metal migration into the environment as confirmed by the synthetic precipitation leaching procedure.
In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power ... more In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power plants. Extraction of metals from FA is an important industrial/environmental issue to assess metals' mobility and applications. Large amounts of metals (V, Ni, Fe, Ca, Mg, Na, and K) were easily leached from FA under acidic, basic, and neutral conditions and this makes disposal of this material an important environmental issue. Extraction and separation of vanadium (V) and nickel (Ni) from FA is achieved using Akita's procedure with some modifications. In the first step, Ni is selectively eluted from FA using NH 4 OH solution and then precipitated using Na 2 S. The Ni/V ratio in final precipitate was 27. On the other hand, V is extracted from Ni-free-FA using Na 2 CO 3 solution, recovered by 0.1 M tri-ethylamine/toluene, and precipitated by NH 4 Cl. The V/Ni ratio in the final precipitate was 55. The adopted method showed a reasonable recovery for both metals from FA, 56 and 45% from Ni and V, respectively. The earlier attempts indicated that separation of V/Ni by precipitation using OH − or CO 3 2− was not successful where both the metals did not precipitate from solution in the presence of other elements.
Abstract This paper investigates the development of stable geopolymers using petroleum fly ash wi... more Abstract This paper investigates the development of stable geopolymers using petroleum fly ash with high compressive strength and water absorption to promote cleaner production, sustainability, and recycling of waste. The paper provided detailed characterizations of the petroleum fly ash, which involved the determination of the particle size diameter, density, surface area, pore-volume, mineralogical identification of recording X-ray diffraction pattern, X-ray fluorescence, Fourier transform infrared, thermogravimetric analysis, and scanning electron microscope. Moreover, metals leachability from the petroleum fly ash using different extracting agents, namely H2SO4, H3PO4, (NH4)2SO4, NH4NO3, and NH4O2CCO2H was also considered. Five geopolymers were prepared using different amounts of petroleum fly ash to assess the influence of petroleum fly ash on the final performance of the prepared geopolymers. The results revealed that the petroleum fly ash was carbonaceous in nature and rich in vanadium oxide and nickel oxide with low in SiO2 and Al2O3. Furthermore, it was found that petroleum fly ash has a low calcium level. The maximum extraction values were 15.6% for V and 55.6% for Ni using H2SO4. All the prepared geopolymers displayed high compressive strength for longer curing times, and the water absorption properties of all geopolymers were improved by incorporating more petroleum fly ash. Increasing the petroleum fly ash from 0 vol% to 61 vol% increased the water absorption value from 6.6 to 13.3 wt% for the samples collected after 28 days of curing. It was concluded that the petroleum fly ash did tend to form successful stable geopolymers with high compressive strength and water absorption.
Abstract This paper investigates the development of stable geopolymers using petroleum fly ash wi... more Abstract This paper investigates the development of stable geopolymers using petroleum fly ash with high compressive strength and water absorption to promote cleaner production, sustainability, and recycling of waste. The paper provided detailed characterizations of the petroleum fly ash, which involved the determination of the particle size diameter, density, surface area, pore-volume, mineralogical identification of recording X-ray diffraction pattern, X-ray fluorescence, Fourier transform infrared, thermogravimetric analysis, and scanning electron microscope. Moreover, metals leachability from the petroleum fly ash using different extracting agents, namely H2SO4, H3PO4, (NH4)2SO4, NH4NO3, and NH4O2CCO2H was also considered. Five geopolymers were prepared using different amounts of petroleum fly ash to assess the influence of petroleum fly ash on the final performance of the prepared geopolymers. The results revealed that the petroleum fly ash was carbonaceous in nature and rich in vanadium oxide and nickel oxide with low in SiO2 and Al2O3. Furthermore, it was found that petroleum fly ash has a low calcium level. The maximum extraction values were 15.6% for V and 55.6% for Ni using H2SO4. All the prepared geopolymers displayed high compressive strength for longer curing times, and the water absorption properties of all geopolymers were improved by incorporating more petroleum fly ash. Increasing the petroleum fly ash from 0 vol% to 61 vol% increased the water absorption value from 6.6 to 13.3 wt% for the samples collected after 28 days of curing. It was concluded that the petroleum fly ash did tend to form successful stable geopolymers with high compressive strength and water absorption.
Low cost building materials have been developed by chemical activation of Jordanian Hiswa kaolini... more Low cost building materials have been developed by chemical activation of Jordanian Hiswa kaolinite with a sodium hydroxide solution. The effect of the main parameters of synthesis and processing on the development of compressive strength was studied. An investigation of the physical, thermal, mineralogical and microstructural properties was performed. A compressive strength of 32 MPa was obtained for a mixture cured at 80°C for 24 h. The mineralogical and microstructural results on the hardened material indicate the formation of sodium zeolite phases and feldspathoids with a Na/Al ratio of one. The high compressive strength observed is directly related to the formation of the new phases that fill the pore spaces and bind the matrix.
Abstract A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to ... more Abstract A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to produce low environmental impact materials from local raw materials. In this paper the emphasis is on the general characteristics of the material and on its durability. With the ...
Three Jordanian raw materials, namely Jordanian Hiswa kaolinite, Jordanian volcanic tuff and Jord... more Three Jordanian raw materials, namely Jordanian Hiswa kaolinite, Jordanian volcanic tuff and Jordanian smectite rich clay, are investigated on their potential for use as an alkali activated cement. A dissolution study of these materials already indicates that the tuff sample reacts slower than the two clay materials. DSC shows that the kaolinite is the most reactive material followed by the smectite rich clay. The tuff is much less reactive. The kaolinite is chosen for producing geopolymer specimens. The optimal amount of NaOH to be added is found to be 16 parts by weight compared to the kaolinite. These specimens have a compressive strength of 33 MPa under dry conditions, after curing for 24h at 80°C. TGA can be used for checking how much kaolinite remains after the geopolymerization.
ABSTRACT In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel ... more ABSTRACT In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power plants. The brackish granular flash ash was systematically analysed by different analytical techniques including scanning electron microscope (SEM), X-ray diffractometer (XRD), X-ray fluorescence (XRF). Fourier transform infrared spectroscopy (FTIR), lazier diffractometer (LD), Thermal gravimetric analysis (TGA) and acoustic and electroacoustic spectrometer in order to investigate geometrical structure, morphology, surface chemistry and composition of the resulted FA. The FA was sampled form the places where heavy fuel is burned to produce electricity. This study revealed that about 50% of FA particles diameters were less than 530 nm. FA particles were predominantly appeared as smooth of mineral spheres. The FA was rich in C, S, Mg, V, Ni and Fe indicating the carbonaceous nature of this material. The Al and Si contents were insignificant. The size distribution, chemical and morphological properties of the FA particles were found to be log-normal. The FA contains high heavy metals content, particularly vanadium oxide (V2O5: 8.07 %wt) and nickel oxide (NiO: 0.91 %wt). Discussion on the physical and chemical characteristics of carbonaceous FA produced in power plants is addressed in this work.
ABSTRACT Results of a shallow drilling program into the moat and central uplift of the Waqf as Su... more ABSTRACT Results of a shallow drilling program into the moat and central uplift of the Waqf as Suwwan impact structure, Jordan are presented. Stratigraphic evidence suggests a deep level of erosion.
The Khushaym Matruk site in Central Jordan is investigated as a natural analogue of a deep geolog... more The Khushaym Matruk site in Central Jordan is investigated as a natural analogue of a deep geological repository for intermediate to high-level radioactive wastes to discuss the impact of high-alkaline solutions in an argillaceous formation. The studied site is characterised by Maestrichtian bituminous-rich marls, consisting of 66-83% of carbonates and 10-15% of clays of mixed-layers illite-smectite type (I-S), overlapped by a marble/cement unit formed by spontaneous in situ combustion of the sedimentary organic matter in sub-surface conditions. This high-temperature event produced marble and cementitious phases typical to those observed in industrial cements whose alteration generates high-alkaline solutions. Evidences of fluid circulations in Khushaym Matruk site are underlined by secondary minerals, mainly calcite and gypsum, neoformed in cracks and micro-cracks crosscutting the bituminous-rich marls, and in travertines capping them. The chemical and Sr isotopic data of these phases are characteristics of high-alkaline fluids generated by alteration of the cementitious phases and having percolated with partial equilibration in the underlying bituminous-rich marls. The propagation of these alkaline solutions by structural discontinuity paths in the clayey formation is underlined over distances greater than 5 m. Also, the mineralogical and petrographic characterisation of the bituminous-rich marls, far and close to the marble/cement unit, emphasizes slight variations in mineral contents, a few metres close to the marble/cement contact, with notably a decrease of I-S crystallinity, a change from beideillite to montmorillonite type and, calcite and zeolite recrystallisation. Together, textural disturbances of these rocks, underlined by micro-fissuration of the sedimentary matrix, are observed. A pervasive circulation of high-alkaline fluids in the argillaceous matrix is proposed to explain these changes and is underlined over a distance of a few metres under the contact with the marble/cement unit. Cathodoluminescence observations and U-Th radioactive disequilibrium dating 0375-6742/$ -see front matter D (I. Techer). www.elsevier.com/locate/jgeoexp applied on infilling calcite cracks indicate that these circulations were not continuous but occurred in several steps with a mean age of 110,000-130,000 years. D
In Jordan, large amounts of fly ash (FA) are produced from heavy fuel composition in power statio... more In Jordan, large amounts of fly ash (FA) are produced from heavy fuel composition in power stations. The produced fly ash is highly contaminated with heavy metals including V, Ni, Zn and Fe. Geopolymer containing different amounts of FA was fabricated for sake of minimising the mobility of toxic elements in the repository site. Using local kaolinite, fly ash and NaOH mixture, five geopolymers were prepared at room temperature and cured at 80 o C at the following ratios: Si/Al: 1.68-4.71, Na 2 O/Al 2 O 3 : 1.48-1.84, Na/Al: 0.74-0.92. The maximum compressive strength was observed for the geopolymer containing no fly ash, 28 Mpa at day 1 and dry sample. A geopolymer containing 10% FA showed promising results where a compressive strength of 23 Mpa was reported. The porosity of FA has been partially destroyed after polymerisation process as indicated from SEM pictures and XRD analysis; new phases have been created under the action of applied pressure. The leachability test indicated that the samples of higher FA are more leachable. The results proved that involving FA in geopolymerisation was significantly decreased the mobility of the toxic metals like Ni and V. Therefore, the prepared geopolymers will definitely have important industrial applications.
Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 2012
ABSTRACT A complex, impact structure was recently discovered at Jebel Waqf as Suwwan, in the cent... more ABSTRACT A complex, impact structure was recently discovered at Jebel Waqf as Suwwan, in the central part of the eastern region of Jordan. Shatter cones and cataclasis of sandstone and limestone from the outer side of the inner central uplift area confirm the impact origin of the Waqf as Suwwan structure. Cataclased and deformed chert fragments, nodules and concretions from the surface regolith layer of the outer inner ring were investigated. The microstructures of the collected samples were investigated using XRD (X-ray diffraction), XRF (X-ray Fluorescence) and ESM-EDX (energy Dispersive X-ray analysis) techniques. Brecciation, dislocation, recrystallization processes, and subplanar jointing and fractures of the chert are among the most important aspects. Additionally, feather features are common planar microstructures in the quartzite breccia. Some of the observations have previously been interpreted as sedimentary features, but since Waqf as Suwwan represents a confirmed impact structure, it is debatable as to whether some of the observed deformation effects are the result of the impact event.
This paper reports an investigation of the oxidation state of Cr in samples of natural céments fo... more This paper reports an investigation of the oxidation state of Cr in samples of natural céments formed 500 ky
The adsorption of lead [Pb(II)] ions onto adsorbents prepared by alkali solid-state conversion of... more The adsorption of lead [Pb(II)] ions onto adsorbents prepared by alkali solid-state conversion of kaolin and natural zeolite mixture was investigated. The adsorption isotherms were obtained and the Langmuir parameters were calculated in order to make a comparison between the adsorption capacities of synthesized adsorbents and those of their constituents. The synthesized adsorbents exhibit much higher adsorption capacity than kaolin and zeolite. Therefore, the low-cost adsorbent based on kaolin and Jordanian zeolite has important features since it has an extraordinary adsorption capacity towards Pb(II) ions (157 mg Pb(II)/g at pH 6.0 and 0.1 M ionic strength). Furthermore, the results implied the advantage of using zeolite as filler in kaolin-based geopolymers and the advantage of using kaolin as a binder for zeolite in their use as industrial adsorbents in water purification. The adsorption capacity of the synthesized adsorbents, unexpectedly, increases with pH decrease and ionic strength increase. The XRD pattern of the synthesized adsorbent prepared from Jordanian kaolin (JK) and zeolite indicates that it is amorphous.
A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to produce l... more A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to produce low environmental impact materials from local raw materials. In this paper the emphasis is on the general characteristics of the material and on its durability. With the used kaolinite, specimens with compressive strength of 41 MPa under dry conditions and 23 MPa under immersed water conditions were obtained. The durability under environmental conditions was good.
The present review of high- and low-temperature minerals demonstrates the value of the pyrometamo... more The present review of high- and low-temperature minerals demonstrates the value of the pyrometamorphic rocks, altered varicolored marble (cement zones), travertine, and regolith in Jordan as analogues of cementitious repositories. The alkaline leachate contains hazardous elements such as Zn, Cd, Fe, Ni, Cu, V, Cr, Fe, Mo, As, Co, U, etc. The sites offer a good chance to investigate the interaction of the circulating high alkaline water with the rocks. The unusual high- and low-temperature minerals proved to be durable elements immobilizers which act as sinks for hazardous trace elements. The identified minerals and the solid solution series are indicators of the long-term behavior of natural analogues of cement-dominated repositories.
Unlike coal fly ash, fly ash of heavy fuel oil has received much less attention in the literature... more Unlike coal fly ash, fly ash of heavy fuel oil has received much less attention in the literature. In this work, detailed physicochemical characterization of heavy fuel oil fly ash (FA) is provided. The ash has a carbonaceous matrix and contains V, Ni, Zn, Cr, Cu, and Pb with variable amounts. V was the most abundant heavy metal with enrichment factor of 277 in the FA. The presence of V in the FA is attributed to the formation of Mg 3 V 2 O 8 oxides at high combustion temperature as confirmed by XRD. Particle size distribution showed that the mean particle diameter of the FA was 70.5 μm. Extraction recovery up to 85% of metals was achieved using 1.0 M HNO 3 and at room temperature. Standard metal-leaching tests confirmed that the elution of the toxic metals and the level of eluted Zn were much higher than the regulated value for the solid residues. Five stable geopolymers GPs containing 41.7 wt.% FA were prepared. All GPs showed high compressive strength and low water absorption which support their application as lightweight construction composites. Most importantly, adding FA to GP had significantly reduced metal migration into the environment as confirmed by the synthetic precipitation leaching procedure.
In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power ... more In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power plants. Extraction of metals from FA is an important industrial/environmental issue to assess metals' mobility and applications. Large amounts of metals (V, Ni, Fe, Ca, Mg, Na, and K) were easily leached from FA under acidic, basic, and neutral conditions and this makes disposal of this material an important environmental issue. Extraction and separation of vanadium (V) and nickel (Ni) from FA is achieved using Akita's procedure with some modifications. In the first step, Ni is selectively eluted from FA using NH 4 OH solution and then precipitated using Na 2 S. The Ni/V ratio in final precipitate was 27. On the other hand, V is extracted from Ni-free-FA using Na 2 CO 3 solution, recovered by 0.1 M tri-ethylamine/toluene, and precipitated by NH 4 Cl. The V/Ni ratio in the final precipitate was 55. The adopted method showed a reasonable recovery for both metals from FA, 56 and 45% from Ni and V, respectively. The earlier attempts indicated that separation of V/Ni by precipitation using OH − or CO 3 2− was not successful where both the metals did not precipitate from solution in the presence of other elements.
Abstract This paper investigates the development of stable geopolymers using petroleum fly ash wi... more Abstract This paper investigates the development of stable geopolymers using petroleum fly ash with high compressive strength and water absorption to promote cleaner production, sustainability, and recycling of waste. The paper provided detailed characterizations of the petroleum fly ash, which involved the determination of the particle size diameter, density, surface area, pore-volume, mineralogical identification of recording X-ray diffraction pattern, X-ray fluorescence, Fourier transform infrared, thermogravimetric analysis, and scanning electron microscope. Moreover, metals leachability from the petroleum fly ash using different extracting agents, namely H2SO4, H3PO4, (NH4)2SO4, NH4NO3, and NH4O2CCO2H was also considered. Five geopolymers were prepared using different amounts of petroleum fly ash to assess the influence of petroleum fly ash on the final performance of the prepared geopolymers. The results revealed that the petroleum fly ash was carbonaceous in nature and rich in vanadium oxide and nickel oxide with low in SiO2 and Al2O3. Furthermore, it was found that petroleum fly ash has a low calcium level. The maximum extraction values were 15.6% for V and 55.6% for Ni using H2SO4. All the prepared geopolymers displayed high compressive strength for longer curing times, and the water absorption properties of all geopolymers were improved by incorporating more petroleum fly ash. Increasing the petroleum fly ash from 0 vol% to 61 vol% increased the water absorption value from 6.6 to 13.3 wt% for the samples collected after 28 days of curing. It was concluded that the petroleum fly ash did tend to form successful stable geopolymers with high compressive strength and water absorption.
Abstract This paper investigates the development of stable geopolymers using petroleum fly ash wi... more Abstract This paper investigates the development of stable geopolymers using petroleum fly ash with high compressive strength and water absorption to promote cleaner production, sustainability, and recycling of waste. The paper provided detailed characterizations of the petroleum fly ash, which involved the determination of the particle size diameter, density, surface area, pore-volume, mineralogical identification of recording X-ray diffraction pattern, X-ray fluorescence, Fourier transform infrared, thermogravimetric analysis, and scanning electron microscope. Moreover, metals leachability from the petroleum fly ash using different extracting agents, namely H2SO4, H3PO4, (NH4)2SO4, NH4NO3, and NH4O2CCO2H was also considered. Five geopolymers were prepared using different amounts of petroleum fly ash to assess the influence of petroleum fly ash on the final performance of the prepared geopolymers. The results revealed that the petroleum fly ash was carbonaceous in nature and rich in vanadium oxide and nickel oxide with low in SiO2 and Al2O3. Furthermore, it was found that petroleum fly ash has a low calcium level. The maximum extraction values were 15.6% for V and 55.6% for Ni using H2SO4. All the prepared geopolymers displayed high compressive strength for longer curing times, and the water absorption properties of all geopolymers were improved by incorporating more petroleum fly ash. Increasing the petroleum fly ash from 0 vol% to 61 vol% increased the water absorption value from 6.6 to 13.3 wt% for the samples collected after 28 days of curing. It was concluded that the petroleum fly ash did tend to form successful stable geopolymers with high compressive strength and water absorption.
Low cost building materials have been developed by chemical activation of Jordanian Hiswa kaolini... more Low cost building materials have been developed by chemical activation of Jordanian Hiswa kaolinite with a sodium hydroxide solution. The effect of the main parameters of synthesis and processing on the development of compressive strength was studied. An investigation of the physical, thermal, mineralogical and microstructural properties was performed. A compressive strength of 32 MPa was obtained for a mixture cured at 80°C for 24 h. The mineralogical and microstructural results on the hardened material indicate the formation of sodium zeolite phases and feldspathoids with a Na/Al ratio of one. The high compressive strength observed is directly related to the formation of the new phases that fill the pore spaces and bind the matrix.
Abstract A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to ... more Abstract A geopolymer produced from Jordanian kaolinite is described in this work. The aim is to produce low environmental impact materials from local raw materials. In this paper the emphasis is on the general characteristics of the material and on its durability. With the ...
Three Jordanian raw materials, namely Jordanian Hiswa kaolinite, Jordanian volcanic tuff and Jord... more Three Jordanian raw materials, namely Jordanian Hiswa kaolinite, Jordanian volcanic tuff and Jordanian smectite rich clay, are investigated on their potential for use as an alkali activated cement. A dissolution study of these materials already indicates that the tuff sample reacts slower than the two clay materials. DSC shows that the kaolinite is the most reactive material followed by the smectite rich clay. The tuff is much less reactive. The kaolinite is chosen for producing geopolymer specimens. The optimal amount of NaOH to be added is found to be 16 parts by weight compared to the kaolinite. These specimens have a compressive strength of 33 MPa under dry conditions, after curing for 24h at 80°C. TGA can be used for checking how much kaolinite remains after the geopolymerization.
ABSTRACT In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel ... more ABSTRACT In Jordan, large amounts of fly ash (FA) are produced as a result of burning heavy fuel in power plants. The brackish granular flash ash was systematically analysed by different analytical techniques including scanning electron microscope (SEM), X-ray diffractometer (XRD), X-ray fluorescence (XRF). Fourier transform infrared spectroscopy (FTIR), lazier diffractometer (LD), Thermal gravimetric analysis (TGA) and acoustic and electroacoustic spectrometer in order to investigate geometrical structure, morphology, surface chemistry and composition of the resulted FA. The FA was sampled form the places where heavy fuel is burned to produce electricity. This study revealed that about 50% of FA particles diameters were less than 530 nm. FA particles were predominantly appeared as smooth of mineral spheres. The FA was rich in C, S, Mg, V, Ni and Fe indicating the carbonaceous nature of this material. The Al and Si contents were insignificant. The size distribution, chemical and morphological properties of the FA particles were found to be log-normal. The FA contains high heavy metals content, particularly vanadium oxide (V2O5: 8.07 %wt) and nickel oxide (NiO: 0.91 %wt). Discussion on the physical and chemical characteristics of carbonaceous FA produced in power plants is addressed in this work.
ABSTRACT Results of a shallow drilling program into the moat and central uplift of the Waqf as Su... more ABSTRACT Results of a shallow drilling program into the moat and central uplift of the Waqf as Suwwan impact structure, Jordan are presented. Stratigraphic evidence suggests a deep level of erosion.
The Khushaym Matruk site in Central Jordan is investigated as a natural analogue of a deep geolog... more The Khushaym Matruk site in Central Jordan is investigated as a natural analogue of a deep geological repository for intermediate to high-level radioactive wastes to discuss the impact of high-alkaline solutions in an argillaceous formation. The studied site is characterised by Maestrichtian bituminous-rich marls, consisting of 66-83% of carbonates and 10-15% of clays of mixed-layers illite-smectite type (I-S), overlapped by a marble/cement unit formed by spontaneous in situ combustion of the sedimentary organic matter in sub-surface conditions. This high-temperature event produced marble and cementitious phases typical to those observed in industrial cements whose alteration generates high-alkaline solutions. Evidences of fluid circulations in Khushaym Matruk site are underlined by secondary minerals, mainly calcite and gypsum, neoformed in cracks and micro-cracks crosscutting the bituminous-rich marls, and in travertines capping them. The chemical and Sr isotopic data of these phases are characteristics of high-alkaline fluids generated by alteration of the cementitious phases and having percolated with partial equilibration in the underlying bituminous-rich marls. The propagation of these alkaline solutions by structural discontinuity paths in the clayey formation is underlined over distances greater than 5 m. Also, the mineralogical and petrographic characterisation of the bituminous-rich marls, far and close to the marble/cement unit, emphasizes slight variations in mineral contents, a few metres close to the marble/cement contact, with notably a decrease of I-S crystallinity, a change from beideillite to montmorillonite type and, calcite and zeolite recrystallisation. Together, textural disturbances of these rocks, underlined by micro-fissuration of the sedimentary matrix, are observed. A pervasive circulation of high-alkaline fluids in the argillaceous matrix is proposed to explain these changes and is underlined over a distance of a few metres under the contact with the marble/cement unit. Cathodoluminescence observations and U-Th radioactive disequilibrium dating 0375-6742/$ -see front matter D (I. Techer). www.elsevier.com/locate/jgeoexp applied on infilling calcite cracks indicate that these circulations were not continuous but occurred in several steps with a mean age of 110,000-130,000 years. D
Preliminary SEM/EDS results of potential new minerals from the varicolored marble of central Jordan, 2023
Preliminary SEM/EDS results of samples collected from the varicolored marbles of Tulul Al Hammam ... more Preliminary SEM/EDS results of samples collected from the varicolored marbles of Tulul Al Hammam site have indicated potential new minerals. Unusual mineralization also occurs in the associated travertine and regolith. The new potential identified phases are (FeCa) and (CaSi) alloys, KZn(Cu,Fe) sulfide, KCuCa sulfate, oxides of FeCa(CrNi), CaFeAl(TiZn), CrMg(ZnAlFe) and Ca(LaCeNd)Th. Among these phases are F-rich Ca-uranate, Ce(U)Ca vanadates, and CaCd and MgAl(CaFe) silicates. All these phases are indicative of formation under reducing/oxidizing conditions as a result of combustion metamorphism. The oxygen supply during combustion was the controlling factor for the formation of the oxides, sulfides and/or sulfates of the RSE and REE. During the combustion events high temperature sulfides were mainly governed by local redox conditions. Conversion of sulfide sulfur to sulfate occurred by oxidative combustion of dispersed sulfur (S 2-)-rich protolith to (S 6+), followed by the liberation of metals bound to the original sulfides and organic matter. Central Jordan pyrometamorphic sites give real-world insights into the outcome of natural analogues modeling results to verify its accuracy.
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