Emad Ewais - Academia.edu (original) (raw)
Papers by Emad Ewais
Biologia plantarum, 1992
SECTION 5-IN VITRO CULTURES Uptake of 14C-sucrose and 14C-NAA by tissue cultures ofNicotiana taba... more SECTION 5-IN VITRO CULTURES Uptake of 14C-sucrose and 14C-NAA by tissue cultures ofNicotiana tabacum and Brassica oleracea in regenerating and non-regenerating cultures
Environmental Science and Pollution Research
For the tendency toward cleaner production and safe conversion of undesired toxic wastes to highl... more For the tendency toward cleaner production and safe conversion of undesired toxic wastes to highly priced advanced products, this work introduces new ceramics/glass composites of Cr2O3/Fe2O3/lead silicate glass (LSG) from industrial LSG wastes. Both chromia Cr2O3 and hematite Fe2O3 ceramics are added equally to the LSG wastes with different percentages (10, 20, and 30 wt.%) via the pressureless sintering method. The competitiveness of this work is dependent on the conversion of undesired waste materials into advanced/smart optical materials with a low cost and an environmentally friendly method. Hence, the influence of both Cr2O3 and Fe2O3 additions on the behavior and the different characteristics of the lead silicate wastes are comprehensively investigated. Evaluation of the final ceramics/glass composites was achieved through their phase composition, microstructure, optical, and magnetic characteristics. The results verified that the insertion of both chromia and hematite togethe...
Refractories and Industrial Ceramics
Hydroxyapatite (HA) synthesized with the hydrothermal method was studied under various preparatio... more Hydroxyapatite (HA) synthesized with the hydrothermal method was studied under various preparation conditions including variations of time, concentration of reactants, and concentration of surfactant, Aminotris (methylenephosphonic acid) [N(CH2PO3H2)3] (ATMP). Well elongated crystals with high degree of crystallinity were synthesized at 150 C, initial pH adjusted to 9.0 ± 0.1 with no surfactant and a high concentration of reactants. Addition of the surfactant helped in increasing particle agglomeration and formation of clusters of micron sizes. HA crystal sizes were ranged from 1.4 μm to 5.1 μm whereas the crystallite sizes ranged from 26 nm to 38 nm. The antiviral screening of the hydroxyapatite was performed against Viruses that represent a threat to the public health community due to their minimal symptomatic control such as HAV, HSV-1, Adenovirus and MERS. The antiviral activities of the synthesized compound were evaluated In vitro by viral infectivity Plaque assay. The obtained...
A successful utilization of two waste metal oxides (Al-slag and silica fumes) in preparing valuab... more A successful utilization of two waste metal oxides (Al-slag and silica fumes) in preparing valuable cordierite ceramic material and the fabrication of the produced cordierite in a 3D porous structure have been achieved through this investigation. The optimum sintering conditions (in terms of sintering temperature and time) for producing dense mixture compact containing lower amount of undesirable phases beside the main desired cordierite phase were determined. The results revealed that a sintering temperature of 1325C and a sintering time of 2 h were the most appropriate conditions during cordierite synthesis. However, the key role for the successful fabrication of a porous ceramic body via replica method is to prepare a well-dispersed suspension from the mixture of raw materials. Herein the optimum conditions for preparing a well-dispersed suspension in terms of type and concentration of additives as well as suspension pH were evaluated. The using of 0.2% sodium silicate and a susp...
NOVYE OGNEUPORY (NEW REFRACTORIES), 2020
In an attempt to optimize a qualified ceramic material with enhanced and outstanding characterist... more In an attempt to optimize a qualified ceramic material with enhanced and outstanding characteristics, the current work aims to study the processing of dense Si 3 N 4 based ceramic composites by hot pressing method. The proposed material consists of an equimolecular mixture of α and β-Si 3 N 4 with adding of variant amounts of MgO‒Al 2 O 3 spinel as sintering additive. Investigation of the different characteristics of the obtained ceramics with respect to densification parameters, hardness, fracture toughness, bending strength and cold crushing strength was performed and correlated to their microstructure behavior. Results indicated that dense well distributed structure of silicon nitride ceramics was attained by adding of variant amounts of the magnesium aluminate spinel structure. Moreover, insertion of MgO‒ Al 2 O 3 mixtures to Si 3 N 4 ceramics was established to enhance their grains growth demeanor, increased the elongated β-Si 3 N 4 grains and their aspect ratio. Furthermore, it was revealed that, increasing MgO ratio relative to Al 2 O 3 one in the spinel structure was responsible for enhancing the different properties of the produced nitride ceramics. Results suggested that the obtained hot pressed Si 3 N 4 ceramics seeded with β-Si 3 N 4 particles can be a successful candidate in automotive industry as alternative parts for the vehicle engines.
NOVYE OGNEUPORY (NEW REFRACTORIES), 2020
In attempts to attain a SHS synthesized TiC‒Al2O3 composite with high density, homogenous microst... more In attempts to attain a SHS synthesized TiC‒Al2O3 composite with high density, homogenous microstructure and extra mechanical properties for using in aggressive media, addition of different reinforcements have to be studied and inspected. In this work, ductile nickel metal powder with different content (5‒20 wt. %) and 1 mole fraction dilution of alumina and zirconia with and without Ni addition are introduced to TiC‒Al2O3 ceramic and synthesized by combined self-propagating high temperature synthesis (SHS) and direct consolidation (DC) technique. The influence of nickel wt. % and dilution with zirconia and alumina on the phase composition, densification behavior, microstructure and mechanical properties of SHS synthesized TiC‒Al2O3 composite has been investigated and analyzed. Results revealed that, addition of 5 wt. % Ni gave the best densification behavior, microstructure and mechanical properties with exact formation of the target composite of TiC‒Al2O3. However, increasing Ni c...
This contribution aims to extract alumina (Al 2 O 3 ) with nanoscale grains in a doubly valuable ... more This contribution aims to extract alumina (Al 2 O 3 ) with nanoscale grains in a doubly valuable (profitable) manner, i.e. extraction of valuable alumina from cheap clays widespread in southern Libya using a simple chemical technique. Four clay samples selected from southern Libya were processed and investigated using XRD and XRF techniques. Alumina was extracted from the processed clay samples using KHSO 4 as a fluxing agent. The extracted alumina samples were investigated by means of XRD, XRF as well as of SEM attached with EDX unit. Nanoparticles of alumina ( 99.5 %) could be obtained from different clay samples. The optimum efficiency of alumina extraction is reached using Sebha clay and KHSO 4 in a molar ratio of 1:7 at a temperature of 500°C for a time period of 3 h. The quality (purity, grain size and efficiency) of the extracted alumina competes with the standard laboratory alumina compound (Alcoa) extracted from a usual bauxite source.
![Research paper thumbnail of Erratum to “Utilization of aluminum sludge and aluminum slag (dross) for the manufacture of calcium aluminate cement” [Ceram. Int. 35 (2009) 3381–3388]](https://attachments.academia-assets.com/101928289/thumbnails/1.jpg)
](Ceramics International, 2010
Interceram, 2009
... AHMED YMZ ; EWAIS EMM ; MOHAMED AM ; ELSHEIKH AM ; ASHOUR I. ; ... It was found that the cord... more ... AHMED YMZ ; EWAIS EMM ; MOHAMED AM ; ELSHEIKH AM ; ASHOUR I. ; ... It was found that the cordierite phase was completely formed at lower temperature of firing of 1300 °C for 2 h. On the other hand, a porous cordierite body was fabricated with Replica method. ...
Advances in Applied Ceramics, 2009
ABSTRACT
Refractories and Industrial Ceramics, 2021
This study aims to investigate the feasibility of alkali activated slag as a sole binder for refr... more This study aims to investigate the feasibility of alkali activated slag as a sole binder for refractory concretes. The concrete samples prepared are subjected to different firing temperatures at 850, 1100 and 1300°C. The mineralogical compositions of the fired concretes are investigated using x-ray diffraction (XRD), and the microstructure is examined using scanning electron microscope (SEM). Also, sintering parameters, mechanical properties as well as refractory properties in terms of permanent linear change (PLC), refractoriness under load (RUL) and thermal shock resistance (TSR) are tested. Variation in sintering parameters and mechanical properties is observed by changing firing temperatures. Refractory concretes based on geopolymers exhibit significant PLC only at 1300°C, the maximum PLC index (0.56%) is observed under load and with an increase in temperature. In addition refractory concretes have a good TSR index (up to 15 cycles). According to XPAanalysis data within fired concretes apart from the main phases within aggregates, there are readily melting phases formed at 850 and 1100°C. Apparently with an increase in temperature there is formation of hibonite and anorthite. A needle-shaped structure is noticed embedded in glassy matrix at 110°C, but the plate-like structure of hibonite is observed at higher temperature. On the whole XPA results reveal that alkali activated slag cement is a promising binder for refractory concretes at high temperature.
NOVYE OGNEUPORY (NEW REFRACTORIES), 2021
Journal of the Korean Ceramic Society
This research presents the possibility of producing durable foam glasses from glass cullet using ... more This research presents the possibility of producing durable foam glasses from glass cullet using SiC/AlN foaming agent. The foaming agent generated by the SiC and AlN couple results in a more homogeneous microstructure and thus the emergence of foam glasses with better properties compared to the nitride foaming agent used alone in our previous work. The fabricated foam had a crack-free, 3-D cellular structure with macropores whose geometries varied between elliptical-, pentagonal-, and hexagonal-shaped constructions. It also had a lightweight (≥ 0.18 g/cm3), high cold crushing strength (≤ 4.5 MPa), low thermal conductivity (0.09–0.16 W/m K), and contained more than ~ 89 vol.% gas bubbles enclosed between 11 vol.% impervious glass walls. The properties accomplished by the foam prepared in this work conform with the requirements of international standard for commercial glass foams, demonstrating its strong capability to be utilized in potential applications in sustainable buildings an...
International Journal of Materials Technology and Innovation
Hydroxyapatite (HA) crystals were synthesized from calcium acetate monohydrate and phosphoric aci... more Hydroxyapatite (HA) crystals were synthesized from calcium acetate monohydrate and phosphoric acid using hydrothermal method. The various interactions of reactant concentrations (1-3 Molar), surfactant {aminotris (methylene phosphonic acid) [N(CH2PO3H2)3] (ATMP)} concentrations (0-100 ppm), and hydrothermal times (6-24 hours) were investigated and their effects on the mean diameter of the HA crystals were obtained using the Box-Behnken experimental statistical design. Results have shown that surfactant has no effect on the mean diameter of the crystals. On the other hand, the results revealed that time and reactant concentration are major parameters in changing the particle size of hydroxyapatite crystals. Without addition of the surfactant, well elongated crystals with high degree of crystallinity were synthesized. With addition of the surfactant, the agglomeration of HA particles as well as hardness of HA pressed discs are significantly increased. HA particles were ranged from 2.7 µm to 7.2 µm as crystal aggregates whereas the obtained crystallite sizes ranged from 17.3 nm to 30.3 nm. Highlights • The paper involves new findings on the synthesis of high hardness hydroxyapatite. • 15 synthesis tests via experimental statistical design were performed with discussion of the results. • Investigations of hydroxyapatite with and without the ATNP surfactant are reported. • The hydroxyapatite hardness is increased with the addition of surfactant.
Refractories and Industrial Ceramics, 2017
Insulating refractory bricks with different densities have been successfully produced from firing... more Insulating refractory bricks with different densities have been successfully produced from firing of sludge of water treatment produced from the water treatment plant at El-Kureimat power station (Giza, Egypt) and rice husk ash mixtures. Different batches from the sludge of water treatment (SWT) with varying amounts of rice husk ash (RHA) were well mixed, formed, dried, and finally fired at different temperatures ranging (800-1200°C). The filter pressed sludge was dried and fired at the same temperature range. The physico-mechanical properties of the fired specimens of sludge-rice husk ash batches and the filtered press sludge were investigated and evaluated. The results showed that the sludge of water treatment plant can be used successfully to produce high quality insulating refractory bricks for various thermal insulating applications.
International Journal of Materials Technology and Innovation
This research presents the possibility of producing durable foam glasses from soda-lime glass was... more This research presents the possibility of producing durable foam glasses from soda-lime glass waste using SiC foaming agent via viscous flow sintering at 900 ℃. The use of SiC instead of the nitride foaming agent applied in a previous work results in a more homogeneous microstructure and thus the emergence of foamed glass with better mechanical properties. The fabricated foam had a crack-free, 3-D cellular structure with closed pores of various geometries. It also had a lightweight (~ 0.233 g/cm 3), high cold crushing strength (CCS) (3.37 MPa), low thermal conductivity (0.105 W/m-K), and contained more than ~ 92.7 vol.% gas bubbles enclosed between 7.3 vol.% impervious glass walls. The properties accomplished by the glass foam prepared in this work conform with the requirements of the international standard for commercial glass foams, demonstrating its strong capability to be utilized in potential applications in sustainable buildings and energy efficiency in the industry.
Engineering non-oxide ceramics have recently been implied in many advanced applications based on ... more Engineering non-oxide ceramics have recently been implied in many advanced applications based on their high temperature capability, outstanding strength, and low fabrication cost. As solar energy has become an economic trend and a clean source of energy; the utilization of ceramic materials as solar receivers in a solar thermal system has been widely considered. Various ceramic materials have shown their ability as heat absorber material due to their oxidation resistance, bending strength, thermal conductivity, and solar absorptance. Ceramics as Si3N4 and SiC can be valuable solar receiver materials; however, due to the high sintering temperature required for Si3N4 and the non-oxidizing nature of SiC; modification of these ceramics with AIN, oxide materials, and other additives is required. One of the highly promising trials that have proved its ability in a solar thermal system is modifying Si3N4 with Al2O3 and AIN that typically results in developing sialon-based ceramics. The lat...
Biologia plantarum, 1992
SECTION 5-IN VITRO CULTURES Uptake of 14C-sucrose and 14C-NAA by tissue cultures ofNicotiana taba... more SECTION 5-IN VITRO CULTURES Uptake of 14C-sucrose and 14C-NAA by tissue cultures ofNicotiana tabacum and Brassica oleracea in regenerating and non-regenerating cultures
Environmental Science and Pollution Research
For the tendency toward cleaner production and safe conversion of undesired toxic wastes to highl... more For the tendency toward cleaner production and safe conversion of undesired toxic wastes to highly priced advanced products, this work introduces new ceramics/glass composites of Cr2O3/Fe2O3/lead silicate glass (LSG) from industrial LSG wastes. Both chromia Cr2O3 and hematite Fe2O3 ceramics are added equally to the LSG wastes with different percentages (10, 20, and 30 wt.%) via the pressureless sintering method. The competitiveness of this work is dependent on the conversion of undesired waste materials into advanced/smart optical materials with a low cost and an environmentally friendly method. Hence, the influence of both Cr2O3 and Fe2O3 additions on the behavior and the different characteristics of the lead silicate wastes are comprehensively investigated. Evaluation of the final ceramics/glass composites was achieved through their phase composition, microstructure, optical, and magnetic characteristics. The results verified that the insertion of both chromia and hematite togethe...
Refractories and Industrial Ceramics
Hydroxyapatite (HA) synthesized with the hydrothermal method was studied under various preparatio... more Hydroxyapatite (HA) synthesized with the hydrothermal method was studied under various preparation conditions including variations of time, concentration of reactants, and concentration of surfactant, Aminotris (methylenephosphonic acid) [N(CH2PO3H2)3] (ATMP). Well elongated crystals with high degree of crystallinity were synthesized at 150 C, initial pH adjusted to 9.0 ± 0.1 with no surfactant and a high concentration of reactants. Addition of the surfactant helped in increasing particle agglomeration and formation of clusters of micron sizes. HA crystal sizes were ranged from 1.4 μm to 5.1 μm whereas the crystallite sizes ranged from 26 nm to 38 nm. The antiviral screening of the hydroxyapatite was performed against Viruses that represent a threat to the public health community due to their minimal symptomatic control such as HAV, HSV-1, Adenovirus and MERS. The antiviral activities of the synthesized compound were evaluated In vitro by viral infectivity Plaque assay. The obtained...
A successful utilization of two waste metal oxides (Al-slag and silica fumes) in preparing valuab... more A successful utilization of two waste metal oxides (Al-slag and silica fumes) in preparing valuable cordierite ceramic material and the fabrication of the produced cordierite in a 3D porous structure have been achieved through this investigation. The optimum sintering conditions (in terms of sintering temperature and time) for producing dense mixture compact containing lower amount of undesirable phases beside the main desired cordierite phase were determined. The results revealed that a sintering temperature of 1325C and a sintering time of 2 h were the most appropriate conditions during cordierite synthesis. However, the key role for the successful fabrication of a porous ceramic body via replica method is to prepare a well-dispersed suspension from the mixture of raw materials. Herein the optimum conditions for preparing a well-dispersed suspension in terms of type and concentration of additives as well as suspension pH were evaluated. The using of 0.2% sodium silicate and a susp...
NOVYE OGNEUPORY (NEW REFRACTORIES), 2020
In an attempt to optimize a qualified ceramic material with enhanced and outstanding characterist... more In an attempt to optimize a qualified ceramic material with enhanced and outstanding characteristics, the current work aims to study the processing of dense Si 3 N 4 based ceramic composites by hot pressing method. The proposed material consists of an equimolecular mixture of α and β-Si 3 N 4 with adding of variant amounts of MgO‒Al 2 O 3 spinel as sintering additive. Investigation of the different characteristics of the obtained ceramics with respect to densification parameters, hardness, fracture toughness, bending strength and cold crushing strength was performed and correlated to their microstructure behavior. Results indicated that dense well distributed structure of silicon nitride ceramics was attained by adding of variant amounts of the magnesium aluminate spinel structure. Moreover, insertion of MgO‒ Al 2 O 3 mixtures to Si 3 N 4 ceramics was established to enhance their grains growth demeanor, increased the elongated β-Si 3 N 4 grains and their aspect ratio. Furthermore, it was revealed that, increasing MgO ratio relative to Al 2 O 3 one in the spinel structure was responsible for enhancing the different properties of the produced nitride ceramics. Results suggested that the obtained hot pressed Si 3 N 4 ceramics seeded with β-Si 3 N 4 particles can be a successful candidate in automotive industry as alternative parts for the vehicle engines.
NOVYE OGNEUPORY (NEW REFRACTORIES), 2020
In attempts to attain a SHS synthesized TiC‒Al2O3 composite with high density, homogenous microst... more In attempts to attain a SHS synthesized TiC‒Al2O3 composite with high density, homogenous microstructure and extra mechanical properties for using in aggressive media, addition of different reinforcements have to be studied and inspected. In this work, ductile nickel metal powder with different content (5‒20 wt. %) and 1 mole fraction dilution of alumina and zirconia with and without Ni addition are introduced to TiC‒Al2O3 ceramic and synthesized by combined self-propagating high temperature synthesis (SHS) and direct consolidation (DC) technique. The influence of nickel wt. % and dilution with zirconia and alumina on the phase composition, densification behavior, microstructure and mechanical properties of SHS synthesized TiC‒Al2O3 composite has been investigated and analyzed. Results revealed that, addition of 5 wt. % Ni gave the best densification behavior, microstructure and mechanical properties with exact formation of the target composite of TiC‒Al2O3. However, increasing Ni c...
This contribution aims to extract alumina (Al 2 O 3 ) with nanoscale grains in a doubly valuable ... more This contribution aims to extract alumina (Al 2 O 3 ) with nanoscale grains in a doubly valuable (profitable) manner, i.e. extraction of valuable alumina from cheap clays widespread in southern Libya using a simple chemical technique. Four clay samples selected from southern Libya were processed and investigated using XRD and XRF techniques. Alumina was extracted from the processed clay samples using KHSO 4 as a fluxing agent. The extracted alumina samples were investigated by means of XRD, XRF as well as of SEM attached with EDX unit. Nanoparticles of alumina ( 99.5 %) could be obtained from different clay samples. The optimum efficiency of alumina extraction is reached using Sebha clay and KHSO 4 in a molar ratio of 1:7 at a temperature of 500°C for a time period of 3 h. The quality (purity, grain size and efficiency) of the extracted alumina competes with the standard laboratory alumina compound (Alcoa) extracted from a usual bauxite source.
Ceramics International, 2010
Interceram, 2009
... AHMED YMZ ; EWAIS EMM ; MOHAMED AM ; ELSHEIKH AM ; ASHOUR I. ; ... It was found that the cord... more ... AHMED YMZ ; EWAIS EMM ; MOHAMED AM ; ELSHEIKH AM ; ASHOUR I. ; ... It was found that the cordierite phase was completely formed at lower temperature of firing of 1300 °C for 2 h. On the other hand, a porous cordierite body was fabricated with Replica method. ...
Advances in Applied Ceramics, 2009
ABSTRACT
Refractories and Industrial Ceramics, 2021
This study aims to investigate the feasibility of alkali activated slag as a sole binder for refr... more This study aims to investigate the feasibility of alkali activated slag as a sole binder for refractory concretes. The concrete samples prepared are subjected to different firing temperatures at 850, 1100 and 1300°C. The mineralogical compositions of the fired concretes are investigated using x-ray diffraction (XRD), and the microstructure is examined using scanning electron microscope (SEM). Also, sintering parameters, mechanical properties as well as refractory properties in terms of permanent linear change (PLC), refractoriness under load (RUL) and thermal shock resistance (TSR) are tested. Variation in sintering parameters and mechanical properties is observed by changing firing temperatures. Refractory concretes based on geopolymers exhibit significant PLC only at 1300°C, the maximum PLC index (0.56%) is observed under load and with an increase in temperature. In addition refractory concretes have a good TSR index (up to 15 cycles). According to XPAanalysis data within fired concretes apart from the main phases within aggregates, there are readily melting phases formed at 850 and 1100°C. Apparently with an increase in temperature there is formation of hibonite and anorthite. A needle-shaped structure is noticed embedded in glassy matrix at 110°C, but the plate-like structure of hibonite is observed at higher temperature. On the whole XPA results reveal that alkali activated slag cement is a promising binder for refractory concretes at high temperature.
NOVYE OGNEUPORY (NEW REFRACTORIES), 2021
Journal of the Korean Ceramic Society
This research presents the possibility of producing durable foam glasses from glass cullet using ... more This research presents the possibility of producing durable foam glasses from glass cullet using SiC/AlN foaming agent. The foaming agent generated by the SiC and AlN couple results in a more homogeneous microstructure and thus the emergence of foam glasses with better properties compared to the nitride foaming agent used alone in our previous work. The fabricated foam had a crack-free, 3-D cellular structure with macropores whose geometries varied between elliptical-, pentagonal-, and hexagonal-shaped constructions. It also had a lightweight (≥ 0.18 g/cm3), high cold crushing strength (≤ 4.5 MPa), low thermal conductivity (0.09–0.16 W/m K), and contained more than ~ 89 vol.% gas bubbles enclosed between 11 vol.% impervious glass walls. The properties accomplished by the foam prepared in this work conform with the requirements of international standard for commercial glass foams, demonstrating its strong capability to be utilized in potential applications in sustainable buildings an...
International Journal of Materials Technology and Innovation
Hydroxyapatite (HA) crystals were synthesized from calcium acetate monohydrate and phosphoric aci... more Hydroxyapatite (HA) crystals were synthesized from calcium acetate monohydrate and phosphoric acid using hydrothermal method. The various interactions of reactant concentrations (1-3 Molar), surfactant {aminotris (methylene phosphonic acid) [N(CH2PO3H2)3] (ATMP)} concentrations (0-100 ppm), and hydrothermal times (6-24 hours) were investigated and their effects on the mean diameter of the HA crystals were obtained using the Box-Behnken experimental statistical design. Results have shown that surfactant has no effect on the mean diameter of the crystals. On the other hand, the results revealed that time and reactant concentration are major parameters in changing the particle size of hydroxyapatite crystals. Without addition of the surfactant, well elongated crystals with high degree of crystallinity were synthesized. With addition of the surfactant, the agglomeration of HA particles as well as hardness of HA pressed discs are significantly increased. HA particles were ranged from 2.7 µm to 7.2 µm as crystal aggregates whereas the obtained crystallite sizes ranged from 17.3 nm to 30.3 nm. Highlights • The paper involves new findings on the synthesis of high hardness hydroxyapatite. • 15 synthesis tests via experimental statistical design were performed with discussion of the results. • Investigations of hydroxyapatite with and without the ATNP surfactant are reported. • The hydroxyapatite hardness is increased with the addition of surfactant.
Refractories and Industrial Ceramics, 2017
Insulating refractory bricks with different densities have been successfully produced from firing... more Insulating refractory bricks with different densities have been successfully produced from firing of sludge of water treatment produced from the water treatment plant at El-Kureimat power station (Giza, Egypt) and rice husk ash mixtures. Different batches from the sludge of water treatment (SWT) with varying amounts of rice husk ash (RHA) were well mixed, formed, dried, and finally fired at different temperatures ranging (800-1200°C). The filter pressed sludge was dried and fired at the same temperature range. The physico-mechanical properties of the fired specimens of sludge-rice husk ash batches and the filtered press sludge were investigated and evaluated. The results showed that the sludge of water treatment plant can be used successfully to produce high quality insulating refractory bricks for various thermal insulating applications.
International Journal of Materials Technology and Innovation
This research presents the possibility of producing durable foam glasses from soda-lime glass was... more This research presents the possibility of producing durable foam glasses from soda-lime glass waste using SiC foaming agent via viscous flow sintering at 900 ℃. The use of SiC instead of the nitride foaming agent applied in a previous work results in a more homogeneous microstructure and thus the emergence of foamed glass with better mechanical properties. The fabricated foam had a crack-free, 3-D cellular structure with closed pores of various geometries. It also had a lightweight (~ 0.233 g/cm 3), high cold crushing strength (CCS) (3.37 MPa), low thermal conductivity (0.105 W/m-K), and contained more than ~ 92.7 vol.% gas bubbles enclosed between 7.3 vol.% impervious glass walls. The properties accomplished by the glass foam prepared in this work conform with the requirements of the international standard for commercial glass foams, demonstrating its strong capability to be utilized in potential applications in sustainable buildings and energy efficiency in the industry.
Engineering non-oxide ceramics have recently been implied in many advanced applications based on ... more Engineering non-oxide ceramics have recently been implied in many advanced applications based on their high temperature capability, outstanding strength, and low fabrication cost. As solar energy has become an economic trend and a clean source of energy; the utilization of ceramic materials as solar receivers in a solar thermal system has been widely considered. Various ceramic materials have shown their ability as heat absorber material due to their oxidation resistance, bending strength, thermal conductivity, and solar absorptance. Ceramics as Si3N4 and SiC can be valuable solar receiver materials; however, due to the high sintering temperature required for Si3N4 and the non-oxidizing nature of SiC; modification of these ceramics with AIN, oxide materials, and other additives is required. One of the highly promising trials that have proved its ability in a solar thermal system is modifying Si3N4 with Al2O3 and AIN that typically results in developing sialon-based ceramics. The lat...