Pub Date : 2021-06-29DOI: 10.53063/synsint.2021.1228
H. Aghajani, S. A. N. Mehrabani, A. T. Tabrizi, Falih Hussein Saddam
In this paper, the synthesis of the copper matrix nanocomposite and the effect of adding TiB2 nanoparticles on the copper matrix was investigated. Three different amounts of TiB2 nanoparticles 5, 10, and 15 wt% were added and sintering was carried out at 900 oC for 4 hours under argon atmosphere. The phase formation of achieved nanocomposites was studied by X-ray diffractometer and the morphology of the synthesized samples was studied by field emission scanning electron microscopy and atomic force microscopy. The polarization and electrochemical impedance spectroscopy (EIS) at 3.5 wt% NaCl solution at room temperature was were carried out to evaluate the corrosion behavior of synthesized samples. Results show that adding the TiB2 nanoparticles decrease the corrosion resistance by the formation of galvanic couples, but the effect of amounts of porosities on the corrosion resistance is higher. It is revealed that the variation of the surface roughness is in direct relation to the value of polarization current density.
{"title":"Corrosion and mechanical behavior evaluation of in-situ synthesized Cu-TiB2 nanocomposite","authors":"H. Aghajani, S. A. N. Mehrabani, A. T. Tabrizi, Falih Hussein Saddam","doi":"10.53063/synsint.2021.1228","DOIUrl":"https://doi.org/10.53063/synsint.2021.1228","url":null,"abstract":"In this paper, the synthesis of the copper matrix nanocomposite and the effect of adding TiB2 nanoparticles on the copper matrix was investigated. Three different amounts of TiB2 nanoparticles 5, 10, and 15 wt% were added and sintering was carried out at 900 oC for 4 hours under argon atmosphere. The phase formation of achieved nanocomposites was studied by X-ray diffractometer and the morphology of the synthesized samples was studied by field emission scanning electron microscopy and atomic force microscopy. The polarization and electrochemical impedance spectroscopy (EIS) at 3.5 wt% NaCl solution at room temperature was were carried out to evaluate the corrosion behavior of synthesized samples. Results show that adding the TiB2 nanoparticles decrease the corrosion resistance by the formation of galvanic couples, but the effect of amounts of porosities on the corrosion resistance is higher. It is revealed that the variation of the surface roughness is in direct relation to the value of polarization current density.","PeriodicalId":22113,"journal":{"name":"Synthesis and Sintering","volume":"118 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87984173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-28DOI: 10.53063/synsint.2021.1229
Asieh Akhoondi, A. Osman, A. Eslami
Dimethyl ether (DME) is a synthetically produced alternative fuel to diesel-based fuel and could be used in ignition diesel engines due to increasing energy demand. DME is considered extremely clean transportation and green fuel because it has a high cetane number (around 60), low boiling point (−25 °C), and high oxygen amount (35 wt%) which allow fast evaporation and higher combustion quality (smoke-free operation and 90% fewer NOx emissions) than other alternative CO2-based fuels. DME can be synthesized from various routes such as coal, petroleum, and bio-based material (i.e., biomass and bio-oil). Dimethyl ether can be produced from CO2 to prevent greenhouse gas emissions. This review aims to summarize recent progress in the field of innovative catalysts for the direct synthesis of dimethyl ether from syngas (CO+H2) and operating conditions. The problems of this process have been raised based on the yield and selectivity of dimethyl ether. However, regardless of how syngas is produced, the estimated total capital and operating costs in the industrial process depend on the type of reactor and the separation method.
{"title":"Direct catalytic production of dimethyl ether from CO and CO2: A review","authors":"Asieh Akhoondi, A. Osman, A. Eslami","doi":"10.53063/synsint.2021.1229","DOIUrl":"https://doi.org/10.53063/synsint.2021.1229","url":null,"abstract":"Dimethyl ether (DME) is a synthetically produced alternative fuel to diesel-based fuel and could be used in ignition diesel engines due to increasing energy demand. DME is considered extremely clean transportation and green fuel because it has a high cetane number (around 60), low boiling point (−25 °C), and high oxygen amount (35 wt%) which allow fast evaporation and higher combustion quality (smoke-free operation and 90% fewer NOx emissions) than other alternative CO2-based fuels. DME can be synthesized from various routes such as coal, petroleum, and bio-based material (i.e., biomass and bio-oil). Dimethyl ether can be produced from CO2 to prevent greenhouse gas emissions. This review aims to summarize recent progress in the field of innovative catalysts for the direct synthesis of dimethyl ether from syngas (CO+H2) and operating conditions. The problems of this process have been raised based on the yield and selectivity of dimethyl ether. However, regardless of how syngas is produced, the estimated total capital and operating costs in the industrial process depend on the type of reactor and the separation method.","PeriodicalId":22113,"journal":{"name":"Synthesis and Sintering","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76830673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-27DOI: 10.53063/synsint.2021.1231
I. Farahbakhsh, R. Antiochia, Ho Won Jang
This research is dedicated to the role of different amounts of hexagonal BN (hBN: 0, 1.5, 3, and 4.5 wt%) on the pressureless sinterability of ZrB2–25 vol% SiC ceramics. Phenolic resin (5 wt%) with a carbon yield of ~40 % was incorporated as a binder to the powder mixtures and after initial cold pressing, the final sintering process was performed at 1900 °C for 100 min in a vacuum furnace. The as-sintered specimens were characterized by X-ray diffractometry, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The results disclosed that the incorporation of 1.5 wt% hBN could increase the relative density to ~92%, while the sample with zero hBN content just reached ~81% of full densification. Appropriate hBN content not only facilitated the particle rearrangement during the cold pressing, but also removed the harmful oxide impurities during the final sintering. Nevertheless, the addition of higher amounts of hBN remarkably lessened the densification because of more delamination of the non-reacted hBN flakes and release and entrapment of more gaseous by-products induced by the reacted hBN phases.
{"title":"Pressureless sinterability study of ZrB2–SiC composites containing hexagonal BN and phenolic resin additives","authors":"I. Farahbakhsh, R. Antiochia, Ho Won Jang","doi":"10.53063/synsint.2021.1231","DOIUrl":"https://doi.org/10.53063/synsint.2021.1231","url":null,"abstract":"This research is dedicated to the role of different amounts of hexagonal BN (hBN: 0, 1.5, 3, and 4.5 wt%) on the pressureless sinterability of ZrB2–25 vol% SiC ceramics. Phenolic resin (5 wt%) with a carbon yield of ~40 % was incorporated as a binder to the powder mixtures and after initial cold pressing, the final sintering process was performed at 1900 °C for 100 min in a vacuum furnace. The as-sintered specimens were characterized by X-ray diffractometry, field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The results disclosed that the incorporation of 1.5 wt% hBN could increase the relative density to ~92%, while the sample with zero hBN content just reached ~81% of full densification. Appropriate hBN content not only facilitated the particle rearrangement during the cold pressing, but also removed the harmful oxide impurities during the final sintering. Nevertheless, the addition of higher amounts of hBN remarkably lessened the densification because of more delamination of the non-reacted hBN flakes and release and entrapment of more gaseous by-products induced by the reacted hBN phases.","PeriodicalId":22113,"journal":{"name":"Synthesis and Sintering","volume":"45 4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82731376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The microbial corrosion of reinforced concrete sewers was inhibited by synthesized cuprous oxide (Cu2O) nanoparticles. The antibacterial characteristics of Cu2O on Acidithiobacillus thiooxidans were investigated by temporal variation of pH, turbidity, and bacterial counting. Three reinforced concrete samples with different weight percentages of electrodeposited Cu2O (0.06 wt%, 0.055 wt %, 0.05 wt %) were used. The bacterial counting showed that the number of bacteria in samples with 0.06, 0.055, and 0.05 wt% of Cu2O was 4.82, 4.42, and 2.94 times lower than the blank sample (BS), respectively. After bacterial growth, the optical density measurement showed that the percentage of turbidity enhancement for samples with 0.06, 0.055, and 0.05 wt% of Cu2O were 108%, 118%, 165%, respectively, while it was 412% for the BS. Moreover, the pilot stage's pH monitoring revealed that the electrodeposited Cu2O lowered the concentration of hydronium between 7 to 81 times compared to the BS. Experiments indicated that slight changes in the amount of electrodeposited Cu2O lead to significant changes in samples' ability to hinder bacterial growth and microbial-induced corrosion.
{"title":"The effect of synthesized Cu2O on the microbial corrosion inhibition of urban concrete sewer systems","authors":"Zahra Khademmodaresi, Fereshteh Bakhtiari, Mohammadmehdi Azizi","doi":"10.53063/synsint.2021.1233","DOIUrl":"https://doi.org/10.53063/synsint.2021.1233","url":null,"abstract":"The microbial corrosion of reinforced concrete sewers was inhibited by synthesized cuprous oxide (Cu2O) nanoparticles. The antibacterial characteristics of Cu2O on Acidithiobacillus thiooxidans were investigated by temporal variation of pH, turbidity, and bacterial counting. Three reinforced concrete samples with different weight percentages of electrodeposited Cu2O (0.06 wt%, 0.055 wt %, 0.05 wt %) were used. The bacterial counting showed that the number of bacteria in samples with 0.06, 0.055, and 0.05 wt% of Cu2O was 4.82, 4.42, and 2.94 times lower than the blank sample (BS), respectively. After bacterial growth, the optical density measurement showed that the percentage of turbidity enhancement for samples with 0.06, 0.055, and 0.05 wt% of Cu2O were 108%, 118%, 165%, respectively, while it was 412% for the BS. Moreover, the pilot stage's pH monitoring revealed that the electrodeposited Cu2O lowered the concentration of hydronium between 7 to 81 times compared to the BS. Experiments indicated that slight changes in the amount of electrodeposited Cu2O lead to significant changes in samples' ability to hinder bacterial growth and microbial-induced corrosion. ","PeriodicalId":22113,"journal":{"name":"Synthesis and Sintering","volume":" 63","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91415444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-03-29DOI: 10.53063/SYNSINT.2021.116
Iman Salahshoori, A. Seyfaee, A. Babapoor
Researchers are currently considering membranes separation processes due to their eco-friendly, process simplicity and high efficiency. Selecting a suitable and efficient operation is the primary concern of researchers in the field of separation industries. In recent decades, polymeric and inorganic membranes in the separation industry have made significant progress. The polymeric and inorganic membranes have been challenged due to their competitiveness in permeability and selectivity factors. A combination of nanoparticle fillers within the polymer matrix is an effective method to increase polymeric and inorganic membranes’ efficiency in separation processes. Mixed matrix membranes (MMMs) have been considered by the separation industry due to high mechanical and physicochemical, and transfer properties. Moreover, gas separation, oil treatment, heavy metal ions removal, water treatment and oil-water separation are common MMMs applications. Selecting suitable polymer blends and fillers is the key to the MMMs construction. The combination of rubbery and glassy polymers with close solubility parameters increases the MMMs performance. The filler type and synthesis methods also affect the morphological and transfer properties of MMMs significantly. Zeolites, graphene oxide (GO), nanosilica, carbon nanotubes (CNTs), zeolite imidazole frameworks (ZIFs) and metal-organic frameworks (MOFs) are used in the MMMs synthesis as fillers. Finally, solution mixing, polymerization in situ and sol-gel are the primary synthesising MMMs methods.
{"title":"Recent advances in synthesis and applications of mixed matrix membranes","authors":"Iman Salahshoori, A. Seyfaee, A. Babapoor","doi":"10.53063/SYNSINT.2021.116","DOIUrl":"https://doi.org/10.53063/SYNSINT.2021.116","url":null,"abstract":"Researchers are currently considering membranes separation processes due to their eco-friendly, process simplicity and high efficiency. Selecting a suitable and efficient operation is the primary concern of researchers in the field of separation industries. In recent decades, polymeric and inorganic membranes in the separation industry have made significant progress. The polymeric and inorganic membranes have been challenged due to their competitiveness in permeability and selectivity factors. A combination of nanoparticle fillers within the polymer matrix is an effective method to increase polymeric and inorganic membranes’ efficiency in separation processes. Mixed matrix membranes (MMMs) have been considered by the separation industry due to high mechanical and physicochemical, and transfer properties. Moreover, gas separation, oil treatment, heavy metal ions removal, water treatment and oil-water separation are common MMMs applications. Selecting suitable polymer blends and fillers is the key to the MMMs construction. The combination of rubbery and glassy polymers with close solubility parameters increases the MMMs performance. The filler type and synthesis methods also affect the morphological and transfer properties of MMMs significantly. Zeolites, graphene oxide (GO), nanosilica, carbon nanotubes (CNTs), zeolite imidazole frameworks (ZIFs) and metal-organic frameworks (MOFs) are used in the MMMs synthesis as fillers. Finally, solution mixing, polymerization in situ and sol-gel are the primary synthesising MMMs methods.","PeriodicalId":22113,"journal":{"name":"Synthesis and Sintering","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83856149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-01-01DOI: 10.53063/synsint.2021.1332
H. Aghajani, M. Roostaei, Shaya Sharif Javaherian, Arvin Taghizadeh Tabrizi, Ali Abdoli Silabi, N. Farzam Mehr
In this paper, the copper-based nanocomposites with TiO2 nanoparticles were synthesized by the self-propagating high-temperature synthesis (SHS) process. The effect of the different amounts of excess copper, in comparison with the stoichiometric ratio (CuO:Ti ratios of 1:1, 2:1, and 3:1), on the phase formation of achieved samples was studied. A thermodynamical study showed that increasing the excess copper powder reduces the adiabatic temperature, which helps the phase formation. The maximum Brinell hardness (89) was obtained for the sample with the CuO:Ti ratio of 1:1. Finally, the wear behavior of the synthesized nanocomposites was evaluated by the pin on disk test, and the variation of friction coefficient and lost weight were measured. The friction coefficient decreased by the formation of phases and distribution of titanium oxide particles during the SHS process in the presence of the stoichiometric ratio of CuO:Ti. Therefore, the wear behavior was improved. The lowest depth of wear trace was measured 0.68 where the ratio of CuO: Ti was 1:1.
{"title":"Wear behavior of self-propagating high-temperature synthesized Cu-TiO2 nanocomposites","authors":"H. Aghajani, M. Roostaei, Shaya Sharif Javaherian, Arvin Taghizadeh Tabrizi, Ali Abdoli Silabi, N. Farzam Mehr","doi":"10.53063/synsint.2021.1332","DOIUrl":"https://doi.org/10.53063/synsint.2021.1332","url":null,"abstract":"In this paper, the copper-based nanocomposites with TiO2 nanoparticles were synthesized by the self-propagating high-temperature synthesis (SHS) process. The effect of the different amounts of excess copper, in comparison with the stoichiometric ratio (CuO:Ti ratios of 1:1, 2:1, and 3:1), on the phase formation of achieved samples was studied. A thermodynamical study showed that increasing the excess copper powder reduces the adiabatic temperature, which helps the phase formation. The maximum Brinell hardness (89) was obtained for the sample with the CuO:Ti ratio of 1:1. Finally, the wear behavior of the synthesized nanocomposites was evaluated by the pin on disk test, and the variation of friction coefficient and lost weight were measured. The friction coefficient decreased by the formation of phases and distribution of titanium oxide particles during the SHS process in the presence of the stoichiometric ratio of CuO:Ti. Therefore, the wear behavior was improved. The lowest depth of wear trace was measured 0.68 where the ratio of CuO: Ti was 1:1.","PeriodicalId":22113,"journal":{"name":"Synthesis and Sintering","volume":"82 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81453613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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