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Jingsong Zhang - One of the best experts on this subject based on the ideXlab platform.

  • thermal decomposition of cyclohexane by Flash Pyrolysis vacuum ultraviolet photoionization time of flight mass spectrometry a study on the initial unimolecular decomposition mechanism
    Physical Chemistry Chemical Physics, 2021
    Co-Authors: Kuanliang Shao, Xinghua Liu, Paul J Jones, Ge Sun, Mariah Gomez, Blake Riser, Jingsong Zhang
    Abstract:

    Thermal decomposition of cyclohexane at temperatures up to 1310 K was performed using Flash Pyrolysis coupled with vacuum ultraviolet (118.2 nm) photoionization time-of-flight mass spectrometry. The experimental results revealed that the major initiation reaction of cyclohexane decomposition was C–C bond fission leading to the formation of 1,6-hexyl diradical. The 1,6-hexyl diradical could isomerize to 1-hexene and decompose into ˙C3H7 + ˙C3H5 and ˙C4H7 + ˙C2H5. The 1,6-hexyl diradical could also undergo direct dissociation; the C4H8 fragment via the 1,4-butyl diradical intermediate was observed, serving as evidence of the 1,6-hexyl diradical mechanism. Quantum chemistry calculations at UCCSD(T)/cc-pVDZ level of theory on the initial reaction pathways of cyclohexane were performed and found to be consistent with the experimental conclusions. Cyclohexyl radical was not observed as an initial intermediate in the Pyrolysis. Benzene was produced from sequential H2 eliminations of cyclohexane at high temperatures.

  • mechanistic study of thermal decomposition of hexamethyldisilane by Flash Pyrolysis vacuum ultraviolet photoionization time of flight mass spectrometry and density functional theory
    Journal of Physical Chemistry A, 2019
    Co-Authors: Xinghua Liu, Jingsong Zhang, Alexis Vazquez, Daxi Wang
    Abstract:

    Thermal decomposition of hexamethyldisilane (HMDS) was studied from room temperature to 1310 K using Flash Pyrolysis vacuum ultraviolet single-photon ionization time-of-flight mass spectrometry (VUV-SPI-TOFMS). Decomposition pathways of HMDS and initial reaction intermediates were also investigated using density functional theory (DFT) at the B3LYP/6-311++G(d,p) level. Unimolecular decomposition reactions of HMDS involving Si-Si and Si-C bond cleavage, as well as decomposition producing Me4Si and :SiMe2 via a three-centered elimination, were determined as the initiation reactions. Me3SiSi(Me)2•, Me4Si, Me3Si•, and :SiMe2 were major products of the initiation reactions. These initial products were apt to decompose by homolytic reactions. Me2Si═CH2, :SiMe2, and other silene/silylene intermediates preferred decomposing through molecular eliminations. Both homolytic and molecular elimination reactions are important in the Pyrolysis of HMDS.

  • mechanism of the thermal decomposition of tetramethylsilane a Flash Pyrolysis vacuum ultraviolet photoionization time of flight mass spectrometry and density functional theory study
    Physical Chemistry Chemical Physics, 2018
    Co-Authors: Jingsong Zhang, Alexis Vazquez, Daxi Wang, Shuyuan Li
    Abstract:

    The thermal decomposition of tetramethylsilane (TMS) was studied over the temperature range of 298–1450 K by combining Flash Pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry (VUV-PI-TOFMS) and density functional theory (DFT). The initial step in TMS Pyrolysis produced a methyl radical (Me˙) and Me3Si˙. Me3Si˙ underwent subsequent loss of a hydrogen atom to form Me2SiCH2 and loss of a methyl radical to form Me2Si:. Isomerizations via 1,2-shift and H2 eliminations were major secondary decomposition reactions of Me2SiCH2 and Me2Si:. Among the various isomers, silylene species containing Si–H bonds, such as :Si(H)CH2CH2CH3, :Si(H)CH2CHCH2, :Si(H)CH2CH3, and :Si(H)CHCH2, played an important role in H2 elimination reactions. On the other hand, silene species were insignificant in H2 eliminations. Unlike the silylene species, H2 elimination of :SiCH2 was energetically unfavorable.

  • mechanism of the thermal decomposition of tetramethylsilane a Flash Pyrolysis vacuum ultraviolet photoionization time of flight mass spectrometry and density functional theory study
    Physical Chemistry Chemical Physics, 2018
    Co-Authors: Xinghua Liu, Jingsong Zhang, Alexis Vazquez, Daxi Wang
    Abstract:

    The thermal decomposition of tetramethylsilane (TMS) was studied over the temperature range of 298-1450 K by combining Flash Pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry (VUV-PI-TOFMS) and density functional theory (DFT). The initial step in TMS Pyrolysis produced a methyl radical (Me˙) and Me3Si˙. Me3Si˙ underwent subsequent loss of a hydrogen atom to form Me2Si[double bond, length as m-dash]CH2 and loss of a methyl radical to form Me2Si:. Isomerizations via 1,2-shift and H2 eliminations were major secondary decomposition reactions of Me2Si[double bond, length as m-dash]CH2 and Me2Si:. Among the various isomers, silylene species containing Si-H bonds, such as :Si(H)CH2CH2CH3, :Si(H)CH2CH[double bond, length as m-dash]CH2, :Si(H)CH2CH3, and :Si(H)CH[double bond, length as m-dash]CH2, played an important role in H2 elimination reactions. On the other hand, silene species were insignificant in H2 eliminations. Unlike the silylene species, H2 elimination of :Si[double bond, length as m-dash]CH2 was energetically unfavorable.

  • thermal decomposition of tetramethylsilane and tetramethylgermane by Flash Pyrolysis vacuum ultraviolet photoionization time of flight mass spectrometry
    International Journal of Mass Spectrometry, 2014
    Co-Authors: Jessy M Lemieux, Jingsong Zhang
    Abstract:

    Abstract Thermal decomposition of tetramethylsilane (TMS) and tetramethylgermane (TMG) was studied on a short time scale of 20–100 μs using Flash Pyrolysis vacuum ultraviolet single-photon ionization time-of-flight mass spectrometry (VUV-SPI-TOFMS). Primary decomposition of TMS and TMG occurred via loss of a methyl radical to form Si(CH 3 ) 3 and Ge(CH 3 ) 3 , respectively. Both the Si(CH 3 ) 3 and Ge(CH 3 ) 3 radicals underwent secondary loss of a second methyl radical to form :Si(CH 3 ) 2 and :Ge(CH 3 ) 2 , respectively. A previously unobserved secondary decomposition process in TMS involving loss of H atom from Si(CH 3 ) 3 followed by elimination of H 2 to form SiC 3 H 8 , SiC 3 H 6 , and SiC 3 H 4 was also identified. Sequential loss of the third and fourth methyl radical with significant formation of Ge and Ge 2 was observed in the TMG Pyrolysis. Loss of a third methyl radical in the TMS Pyrolysis was not significant, while Si and SiC products were possibly produced. Secondary reactions of methyl to form unsaturated C x H y species, particularly in the TMG decomposition, were also observed.

Martin Olazar - One of the best experts on this subject based on the ideXlab platform.

  • waste truck tyre processing by Flash Pyrolysis in a conical spouted bed reactor
    Energy Conversion and Management, 2017
    Co-Authors: Gartzen Lopez, Maider Amutio, Jon Alvarez, Javier Bilbao, N M Mkhize, B Danon, P Van Der Gryp, Johann F Gorgens, Martin Olazar
    Abstract:

    Abstract The Flash Pyrolysis of waste truck-tyres was studied in a conical spouted bed reactor (CSBR) operating in continuous regime. The influence of temperature on product distribution was analysed in the 425–575 °C range. A detailed characterization of the Pyrolysis products was carried out in order to assess their most feasible application. Moreover, special attention was paid to the sulphur distribution among the products. The analysis of gaseous products was carried out using a micro-GC and the tyre Pyrolysis oil (TPO) by means of GC-FID using peak areas for quantification, with GC/MS for identification and elemental analysis. Finally, the char was subjected to elemental analysis and surface characterization. According to the results, 475 °C is an appropriate temperature for the Pyrolysis of waste tyres, given that it ensures total devolatilisation of tyre rubber and a high TPO yield, 58.2 wt.%. Moreover, the quality of the oil is optimum at this temperature, especially in terms of high concentrations of valuable chemicals, such as limonene. An increase in temperature to 575 °C reduced the TPO yield to 53.9 wt.% and substantially changed its chemical composition by increasing the aromatic content. However, the quality of the recovered char was improved at high temperatures.

  • sewage sludge valorization by Flash Pyrolysis in a conical spouted bed reactor
    Chemical Engineering Journal, 2015
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Itsaso Barbarias, Martin Olazar
    Abstract:

    Abstract Sewage sludge valorization by Flash Pyrolysis has been carried out in a conical spouted bed reactor with continuous biomass feed and char removal. The effect of temperature on product yields and composition has been studied in the 450–600 °C range and a maximum liquid yield of 77 wt.% daf (dry and ash free basis) has been obtained at 500 °C. The liquid collected has a water content of 23–27 wt.% and is mainly composed of oxygen-containing compounds (phenols, ketones and acids amongst others), whose yield decreases with temperature, and nitrogen-containing compounds, such as amides and pyrroles. In addition, the importance of an efficient char removal system has been assessed by operating with and without char accumulation in the bed. The char fraction retains most of the heavy metals contained in the sludge and they may have applications in agriculture or as adsorbent.

  • Performance of a conical spouted bed pilot plant for bio-oil production by poplar Flash Pyrolysis
    Fuel Processing Technology, 2015
    Co-Authors: Jon Makibar, A. Ruth Fernandez-akarregi, Gartzen Lopez, Maider Amutio, Martin Olazar
    Abstract:

    Abstract Poplar (Populus nigra) Flash Pyrolysis has been performed at the IK4-Ikerlan 25 kg h-1pilot plant equipped with a conical spouted bed reactor. Gas, bio-oil and char yields and properties have been studied in the 425-525°C range. This reactor has been proven to be especially suitable for this process as high bio-oil yields have been obtained, with the maximum being 69 wt.% at 455°C. The bio-oil has been collected in two fractions: the lighter one, which accounts for 85 wt.% of the bio-oil, has a high water content and is composed mainly of acids and ketones, whereas the heavier fraction has a lower water content and is rich in phenols. These fractions are miscible, obtaining a bio-oil with a water content lower than 25 wt.% and a higher heating value in the 16-18 MJ kg-1range.

  • upgrading the rice husk char obtained by Flash Pyrolysis for the production of amorphous silica and high quality activated carbon
    Bioresource Technology, 2014
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Martin Olazar
    Abstract:

    Abstract The overall valorization of rice husk char obtained by Flash Pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous Flash Pyrolysis in a conical spouted bed reactor at 500 °C. Extraction with Na 2 CO 3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800 °C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365 m 2  g −1 at the end of 15 min.

  • Flash Pyrolysis of forestry residues from the portuguese central inland region within the framework of the biorefina ter project
    Bioresource Technology, 2013
    Co-Authors: Maider Amutio, Gartzen Lopez, Martin Olazar, Jon Alvarez, Rui Moreira, Gustavo V Duarte, Joao Osvaldo Rodrigues Nunes, Javier Bilbao
    Abstract:

    The feasibility of the valorization by Flash Pyrolysis of forest shrub wastes, namely bushes (Cytisus multiflorus, Spartium junceum, Acacia dealbata and Pterospartum tridentatum) has been studied in a conical spouted bed reactor operating at 500 °C, with a continuous biomass feed and char removal. High bio-oil yields in the 75-80 wt.% range have been obtained for all of the materials, with char yields between 16 and 23 wt.% and low gas yields (4-5 wt.%). Bio-oils are composed mainly of water (accounting for a concentration in the 34-40 wt.% range in the bio-oil), phenols, ketones, acids and furans, with lower contents of saccharides, aldehydes and alcohols. Although their composition depends on the raw material, the compounds are similar to those obtained with more conventional feedstocks.

Maider Amutio - One of the best experts on this subject based on the ideXlab platform.

  • waste truck tyre processing by Flash Pyrolysis in a conical spouted bed reactor
    Energy Conversion and Management, 2017
    Co-Authors: Gartzen Lopez, Maider Amutio, Jon Alvarez, Javier Bilbao, N M Mkhize, B Danon, P Van Der Gryp, Johann F Gorgens, Martin Olazar
    Abstract:

    Abstract The Flash Pyrolysis of waste truck-tyres was studied in a conical spouted bed reactor (CSBR) operating in continuous regime. The influence of temperature on product distribution was analysed in the 425–575 °C range. A detailed characterization of the Pyrolysis products was carried out in order to assess their most feasible application. Moreover, special attention was paid to the sulphur distribution among the products. The analysis of gaseous products was carried out using a micro-GC and the tyre Pyrolysis oil (TPO) by means of GC-FID using peak areas for quantification, with GC/MS for identification and elemental analysis. Finally, the char was subjected to elemental analysis and surface characterization. According to the results, 475 °C is an appropriate temperature for the Pyrolysis of waste tyres, given that it ensures total devolatilisation of tyre rubber and a high TPO yield, 58.2 wt.%. Moreover, the quality of the oil is optimum at this temperature, especially in terms of high concentrations of valuable chemicals, such as limonene. An increase in temperature to 575 °C reduced the TPO yield to 53.9 wt.% and substantially changed its chemical composition by increasing the aromatic content. However, the quality of the recovered char was improved at high temperatures.

  • sewage sludge valorization by Flash Pyrolysis in a conical spouted bed reactor
    Chemical Engineering Journal, 2015
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Itsaso Barbarias, Martin Olazar
    Abstract:

    Abstract Sewage sludge valorization by Flash Pyrolysis has been carried out in a conical spouted bed reactor with continuous biomass feed and char removal. The effect of temperature on product yields and composition has been studied in the 450–600 °C range and a maximum liquid yield of 77 wt.% daf (dry and ash free basis) has been obtained at 500 °C. The liquid collected has a water content of 23–27 wt.% and is mainly composed of oxygen-containing compounds (phenols, ketones and acids amongst others), whose yield decreases with temperature, and nitrogen-containing compounds, such as amides and pyrroles. In addition, the importance of an efficient char removal system has been assessed by operating with and without char accumulation in the bed. The char fraction retains most of the heavy metals contained in the sludge and they may have applications in agriculture or as adsorbent.

  • Performance of a conical spouted bed pilot plant for bio-oil production by poplar Flash Pyrolysis
    Fuel Processing Technology, 2015
    Co-Authors: Jon Makibar, A. Ruth Fernandez-akarregi, Gartzen Lopez, Maider Amutio, Martin Olazar
    Abstract:

    Abstract Poplar (Populus nigra) Flash Pyrolysis has been performed at the IK4-Ikerlan 25 kg h-1pilot plant equipped with a conical spouted bed reactor. Gas, bio-oil and char yields and properties have been studied in the 425-525°C range. This reactor has been proven to be especially suitable for this process as high bio-oil yields have been obtained, with the maximum being 69 wt.% at 455°C. The bio-oil has been collected in two fractions: the lighter one, which accounts for 85 wt.% of the bio-oil, has a high water content and is composed mainly of acids and ketones, whereas the heavier fraction has a lower water content and is rich in phenols. These fractions are miscible, obtaining a bio-oil with a water content lower than 25 wt.% and a higher heating value in the 16-18 MJ kg-1range.

  • upgrading the rice husk char obtained by Flash Pyrolysis for the production of amorphous silica and high quality activated carbon
    Bioresource Technology, 2014
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Martin Olazar
    Abstract:

    Abstract The overall valorization of rice husk char obtained by Flash Pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous Flash Pyrolysis in a conical spouted bed reactor at 500 °C. Extraction with Na 2 CO 3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800 °C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365 m 2  g −1 at the end of 15 min.

  • Flash Pyrolysis of forestry residues from the portuguese central inland region within the framework of the biorefina ter project
    Bioresource Technology, 2013
    Co-Authors: Maider Amutio, Gartzen Lopez, Martin Olazar, Jon Alvarez, Rui Moreira, Gustavo V Duarte, Joao Osvaldo Rodrigues Nunes, Javier Bilbao
    Abstract:

    The feasibility of the valorization by Flash Pyrolysis of forest shrub wastes, namely bushes (Cytisus multiflorus, Spartium junceum, Acacia dealbata and Pterospartum tridentatum) has been studied in a conical spouted bed reactor operating at 500 °C, with a continuous biomass feed and char removal. High bio-oil yields in the 75-80 wt.% range have been obtained for all of the materials, with char yields between 16 and 23 wt.% and low gas yields (4-5 wt.%). Bio-oils are composed mainly of water (accounting for a concentration in the 34-40 wt.% range in the bio-oil), phenols, ketones, acids and furans, with lower contents of saccharides, aldehydes and alcohols. Although their composition depends on the raw material, the compounds are similar to those obtained with more conventional feedstocks.

Gartzen Lopez - One of the best experts on this subject based on the ideXlab platform.

  • waste truck tyre processing by Flash Pyrolysis in a conical spouted bed reactor
    Energy Conversion and Management, 2017
    Co-Authors: Gartzen Lopez, Maider Amutio, Jon Alvarez, Javier Bilbao, N M Mkhize, B Danon, P Van Der Gryp, Johann F Gorgens, Martin Olazar
    Abstract:

    Abstract The Flash Pyrolysis of waste truck-tyres was studied in a conical spouted bed reactor (CSBR) operating in continuous regime. The influence of temperature on product distribution was analysed in the 425–575 °C range. A detailed characterization of the Pyrolysis products was carried out in order to assess their most feasible application. Moreover, special attention was paid to the sulphur distribution among the products. The analysis of gaseous products was carried out using a micro-GC and the tyre Pyrolysis oil (TPO) by means of GC-FID using peak areas for quantification, with GC/MS for identification and elemental analysis. Finally, the char was subjected to elemental analysis and surface characterization. According to the results, 475 °C is an appropriate temperature for the Pyrolysis of waste tyres, given that it ensures total devolatilisation of tyre rubber and a high TPO yield, 58.2 wt.%. Moreover, the quality of the oil is optimum at this temperature, especially in terms of high concentrations of valuable chemicals, such as limonene. An increase in temperature to 575 °C reduced the TPO yield to 53.9 wt.% and substantially changed its chemical composition by increasing the aromatic content. However, the quality of the recovered char was improved at high temperatures.

  • sewage sludge valorization by Flash Pyrolysis in a conical spouted bed reactor
    Chemical Engineering Journal, 2015
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Itsaso Barbarias, Martin Olazar
    Abstract:

    Abstract Sewage sludge valorization by Flash Pyrolysis has been carried out in a conical spouted bed reactor with continuous biomass feed and char removal. The effect of temperature on product yields and composition has been studied in the 450–600 °C range and a maximum liquid yield of 77 wt.% daf (dry and ash free basis) has been obtained at 500 °C. The liquid collected has a water content of 23–27 wt.% and is mainly composed of oxygen-containing compounds (phenols, ketones and acids amongst others), whose yield decreases with temperature, and nitrogen-containing compounds, such as amides and pyrroles. In addition, the importance of an efficient char removal system has been assessed by operating with and without char accumulation in the bed. The char fraction retains most of the heavy metals contained in the sludge and they may have applications in agriculture or as adsorbent.

  • Performance of a conical spouted bed pilot plant for bio-oil production by poplar Flash Pyrolysis
    Fuel Processing Technology, 2015
    Co-Authors: Jon Makibar, A. Ruth Fernandez-akarregi, Gartzen Lopez, Maider Amutio, Martin Olazar
    Abstract:

    Abstract Poplar (Populus nigra) Flash Pyrolysis has been performed at the IK4-Ikerlan 25 kg h-1pilot plant equipped with a conical spouted bed reactor. Gas, bio-oil and char yields and properties have been studied in the 425-525°C range. This reactor has been proven to be especially suitable for this process as high bio-oil yields have been obtained, with the maximum being 69 wt.% at 455°C. The bio-oil has been collected in two fractions: the lighter one, which accounts for 85 wt.% of the bio-oil, has a high water content and is composed mainly of acids and ketones, whereas the heavier fraction has a lower water content and is rich in phenols. These fractions are miscible, obtaining a bio-oil with a water content lower than 25 wt.% and a higher heating value in the 16-18 MJ kg-1range.

  • upgrading the rice husk char obtained by Flash Pyrolysis for the production of amorphous silica and high quality activated carbon
    Bioresource Technology, 2014
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Martin Olazar
    Abstract:

    Abstract The overall valorization of rice husk char obtained by Flash Pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous Flash Pyrolysis in a conical spouted bed reactor at 500 °C. Extraction with Na 2 CO 3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800 °C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365 m 2  g −1 at the end of 15 min.

  • Flash Pyrolysis of forestry residues from the portuguese central inland region within the framework of the biorefina ter project
    Bioresource Technology, 2013
    Co-Authors: Maider Amutio, Gartzen Lopez, Martin Olazar, Jon Alvarez, Rui Moreira, Gustavo V Duarte, Joao Osvaldo Rodrigues Nunes, Javier Bilbao
    Abstract:

    The feasibility of the valorization by Flash Pyrolysis of forest shrub wastes, namely bushes (Cytisus multiflorus, Spartium junceum, Acacia dealbata and Pterospartum tridentatum) has been studied in a conical spouted bed reactor operating at 500 °C, with a continuous biomass feed and char removal. High bio-oil yields in the 75-80 wt.% range have been obtained for all of the materials, with char yields between 16 and 23 wt.% and low gas yields (4-5 wt.%). Bio-oils are composed mainly of water (accounting for a concentration in the 34-40 wt.% range in the bio-oil), phenols, ketones, acids and furans, with lower contents of saccharides, aldehydes and alcohols. Although their composition depends on the raw material, the compounds are similar to those obtained with more conventional feedstocks.

Javier Bilbao - One of the best experts on this subject based on the ideXlab platform.

  • waste truck tyre processing by Flash Pyrolysis in a conical spouted bed reactor
    Energy Conversion and Management, 2017
    Co-Authors: Gartzen Lopez, Maider Amutio, Jon Alvarez, Javier Bilbao, N M Mkhize, B Danon, P Van Der Gryp, Johann F Gorgens, Martin Olazar
    Abstract:

    Abstract The Flash Pyrolysis of waste truck-tyres was studied in a conical spouted bed reactor (CSBR) operating in continuous regime. The influence of temperature on product distribution was analysed in the 425–575 °C range. A detailed characterization of the Pyrolysis products was carried out in order to assess their most feasible application. Moreover, special attention was paid to the sulphur distribution among the products. The analysis of gaseous products was carried out using a micro-GC and the tyre Pyrolysis oil (TPO) by means of GC-FID using peak areas for quantification, with GC/MS for identification and elemental analysis. Finally, the char was subjected to elemental analysis and surface characterization. According to the results, 475 °C is an appropriate temperature for the Pyrolysis of waste tyres, given that it ensures total devolatilisation of tyre rubber and a high TPO yield, 58.2 wt.%. Moreover, the quality of the oil is optimum at this temperature, especially in terms of high concentrations of valuable chemicals, such as limonene. An increase in temperature to 575 °C reduced the TPO yield to 53.9 wt.% and substantially changed its chemical composition by increasing the aromatic content. However, the quality of the recovered char was improved at high temperatures.

  • sewage sludge valorization by Flash Pyrolysis in a conical spouted bed reactor
    Chemical Engineering Journal, 2015
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Itsaso Barbarias, Martin Olazar
    Abstract:

    Abstract Sewage sludge valorization by Flash Pyrolysis has been carried out in a conical spouted bed reactor with continuous biomass feed and char removal. The effect of temperature on product yields and composition has been studied in the 450–600 °C range and a maximum liquid yield of 77 wt.% daf (dry and ash free basis) has been obtained at 500 °C. The liquid collected has a water content of 23–27 wt.% and is mainly composed of oxygen-containing compounds (phenols, ketones and acids amongst others), whose yield decreases with temperature, and nitrogen-containing compounds, such as amides and pyrroles. In addition, the importance of an efficient char removal system has been assessed by operating with and without char accumulation in the bed. The char fraction retains most of the heavy metals contained in the sludge and they may have applications in agriculture or as adsorbent.

  • upgrading the rice husk char obtained by Flash Pyrolysis for the production of amorphous silica and high quality activated carbon
    Bioresource Technology, 2014
    Co-Authors: Jon Alvarez, Gartzen Lopez, Maider Amutio, Javier Bilbao, Martin Olazar
    Abstract:

    Abstract The overall valorization of rice husk char obtained by Flash Pyrolysis in a conical spouted bed reactor (CSBR) has been studied in a two-step process. Thus, silica has been recovered in a first step and the remaining carbon material has been subjected to steam activation. The char samples used in this study have been obtained by continuous Flash Pyrolysis in a conical spouted bed reactor at 500 °C. Extraction with Na 2 CO 3 allows recovering 88% of the silica contained in the rice husk char. Activation of the silica-free rice husk char has been carried out in a fixed bed reactor at 800 °C using steam as activating agent. The porous structure of the activated carbons produced includes a combination of micropores and mesopores, with a BET surface area of up to 1365 m 2  g −1 at the end of 15 min.

  • Flash Pyrolysis of forestry residues from the portuguese central inland region within the framework of the biorefina ter project
    Bioresource Technology, 2013
    Co-Authors: Maider Amutio, Gartzen Lopez, Martin Olazar, Jon Alvarez, Rui Moreira, Gustavo V Duarte, Joao Osvaldo Rodrigues Nunes, Javier Bilbao
    Abstract:

    The feasibility of the valorization by Flash Pyrolysis of forest shrub wastes, namely bushes (Cytisus multiflorus, Spartium junceum, Acacia dealbata and Pterospartum tridentatum) has been studied in a conical spouted bed reactor operating at 500 °C, with a continuous biomass feed and char removal. High bio-oil yields in the 75-80 wt.% range have been obtained for all of the materials, with char yields between 16 and 23 wt.% and low gas yields (4-5 wt.%). Bio-oils are composed mainly of water (accounting for a concentration in the 34-40 wt.% range in the bio-oil), phenols, ketones, acids and furans, with lower contents of saccharides, aldehydes and alcohols. Although their composition depends on the raw material, the compounds are similar to those obtained with more conventional feedstocks.

  • biomass oxidative Flash Pyrolysis autothermal operation yields and product properties
    Energy & Fuels, 2012
    Co-Authors: Maider Amutio, Gartzen Lopez, Javier Bilbao, Roberto Aguado, Martin Olazar
    Abstract:

    Biomass autothermal Flash Pyrolysis has been carried out by adding oxygen to the reaction environment in a bench-scale plant provided with a conical spouted bed reactor, at 500 °C and using two oxygen concentrations in the inlet gas stream (2.5 and 4.1 vol %, which correspond to equivalence ratios of 15 and 25, respectively). An increase in the oxygen concentration leads to an increase in gas and water yields, whereas there is a decrease in the yield of both char (partially burned) and organic compounds in the bio-oil, albeit only slightly in the latter case. Bio-oil composition undergoes only minor changes for certain individual components. The experimental results highlight the advantages of the conical spouted bed reactor (CSBR) for scaling up the autothermal operation. A study on energy requirements reveals that the oxygen concentration needed to achieve autothermal operation decreases as the scale is larger. The oxygen content required in the inlet gas stream for autothermal operation in an industria...