Joël Blin | CIRAD - Academia.edu (original) (raw)
Papers by Joël Blin
Ce document a vocation a presenter quelques elements d 'etat des lieux de la situation au Bur... more Ce document a vocation a presenter quelques elements d 'etat des lieux de la situation au Burkina Faso plutot qu'une analyse, en vue de faciliter les echanges et les comparaisons entre pays autour des enjeux et perspectives des biocarburants pour l'Afrique lors de la conference. Les themes abordes concernent le contexte general de l'agriculture, le contexte environnemental, le contexte energetique et le contexte des biocarburants. Les donnees sont quelquefois partielles mais seront completees apres la conference. Les principales sources statistiques et references bibliographiques utilisees sont listees en fin de document. (Resume d'auteur)
Journal of Renewable and Sustainable Energy, 2013
In West African countries, the objective of producer insertion in competitive markets is often as... more In West African countries, the objective of producer insertion in competitive markets is often associated with the need to modernize and mechanize production processes, i.e., replace labour by machines. This excludes traditional producers who can barely comply with the economic criteria but who must remain competitive to generate higher incomes. The challenge is to improve the efficiency of traditional methods in supply chains rather than imposing modern technologies that producers hardly adopt. Moreover, West African populations suffer from not having cheap and available energy sources. They, therefore, have to be imaginative for more efficient energy use in order to improve the productivity and quality of their products and support sustainable rural development and incomes. Building on the case study of the shea butter supply chain in Burkina Faso, this article proposes an original approach consisting of improved energy use for a more competitive and sustainable activity. The traditional butter production process consumes a great deal of energy from firewood and generates a lot of organic waste that could be used as an energy source. We examined the feasibility of using alternative energy techniques that could be taken on board as they are simple and designed from local resources, whilst using by-products from the shea butter production chain as biofuels to partially replace firewood. We showed that using alternative energy techniques, taken one by one or combined, can lead to lower energy use and thereby increase women's incomes, whilst helping to conserve forests. V C 2013 AIP Publishing LLC.
Renewable and Sustainable Energy Reviews, 2014
ABSTRACT The conversion of biomass by thermochemical means is very promising for the substitution... more ABSTRACT The conversion of biomass by thermochemical means is very promising for the substitution of fossil materials in many energy applications. Given the complexity of biomass the main challenge in its use is to obtain products with high yield and purity. For a better understanding of biomass thermochemical conversion, many authors have studied in TG analyzer or at bed scale the individual pyrolysis of its main constituents (i.e. cellulose, hemicelluloses and lignin). Based on these studies, this original work synthesizes the main steps of conversion and the composition of the products obtained from each constituent. Pyrolysis conversion can be described as the superposition of three main pathways (char formation, depolymerization and fragmentation) and secondary reactions. Lignin, which is composed of many benzene rings, gives the highest char yield and its depolymerization leads to various phenols. The depolymerization of the polysaccharides is a source of anhydro-saccharides and furan compounds. The fragmentation of the different constituents and the secondary reactions produce CO, CO2 and small chain compounds. For temperature higher than 500 °C, the residues obtained from the different constituents present a similar structure, which evolves towards a more condensed polyaromatic form by releasing CH4, CO and H2. As the aromatic rings and their substituent composition have a critical influence on the reactivity of pyrolysis products, a particular attention has been given to their formation. Some mechanisms are proposed to explain the formation of the main products. From the results of this study it is possible to predict the reactivity and energy content of the pyrolysis products and evaluate their potential use as biofuels in renewable applications.
Poor access to energy is now a key challenge to the development of many countries in the South. E... more Poor access to energy is now a key challenge to the development of many countries in the South. Energy supply has become a strategic priority for economic development policies, especially through developing renewable energies. In West Africa, more than 80 % of household energy is provided by biomass (firewood and charcoal). The challenge for developing countries is now moving from a domestic use of biomass energy to a modern use. The latter will help produce energy which remains essential to economic and social development. Indeed, despite their abundance on the African continent, many natural resources and raw materials are not valued and transformed into high value added products because of the lack of access to affordable power services. In 2004, biofuels aroused the enthusiasm of investors who invested on the sector while claiming their participation in the economic and social development of the continent. But in 2007, the rush for this green oil slowed down and the first review...
Renewable and Sustainable Energy Reviews, 2012
Biomass and Bioenergy, 2015
ABSTRACT In this work, we prepared iron- or nickel-impregnated cellulose to examine the influence... more ABSTRACT In this work, we prepared iron- or nickel-impregnated cellulose to examine the influence of the metal on the yield and composition of fast pyrolysis products. In order to identify the mechanisms promoted during the catalytic conversion, pyrolysis was investigated using an experimental set-up coupling TG (thermogravimetric) analysis and Micro-GC (Gas Chromatography). The results showed that with relatively low catalyst loading (mass fraction of 1.5% Fe or 1.7% Ni) impregnated metal can catalyze some rearrangement reactions such as dehydration and decarboxylation starting from 180 °C, promoting the char formation and thus inhibiting cellulose depolymerization. As a consequence metal impregnation led to a decrease of tar and CO yields balanced by an increase of char, H2O and CO2 yields. Depending on the applied metal, other primary reactions can be specifically catalyzed. In particular, in the presence of nickel TG analysis revealed an important mass loss at temperatures as low as 210 °C and an important increase of H2 production in the temperature range 400–500 °C. These findings open promising perspectives to optimize the production of fuels and chemicals from biomass.
Journal of the Chemical Society, Dalton Transactions, 1999
The lability of the SiO→M interaction unique to some bimetallic complexes may confer hemilabile p... more The lability of the SiO→M interaction unique to some bimetallic complexes may confer hemilabile properties to the Si(OR) 3 ligand and various bifunctional phosphines P-Z have been used in order to evaluate the possible competition for co-ordination between the bridging SiO→M interaction and P-Z chelation. Thus, treatment of the heterobimetallic complexes [(OC) 3 Fe{µ-Si(OMe) 2 (OMe)}(µ-dppm)MCl] (M = Pd 4 or Pt 6; dppm = Ph 2 PCH 2 PPh 2 ) and [(OC) 3 Fe{µ-Si(OMe) 2 (OMe)}(µ-dppa)PdCl] 5 (dppa = Ph 2 PNHPPh 2 ) with TlPF 6 in the presence of P-Z afforded the corresponding cationic compounds
Au Burkina Faso, les ressources énergétiques sont rares, et l’énergie importée coûte cher du fait... more Au Burkina Faso, les ressources énergétiques sont rares, et l’énergie importée coûte cher du fait de l’enclavement du pays. Dans ce contexte, le développement de la culture d’agrocarburants ne pourrait-elle pas être un levier pour le développement du pays et de son agriculture ?
ABSTRACT Présentation : L. VAN DE STEENE
Les filières de valorisation énergétique de la biomasse par voies thermochimiques présentent l’int... more Les filières de valorisation énergétique de la biomasse par voies thermochimiques présentent l’intérêt de pouvoir convertir toute matière ligno-cellulosique soit directement en énergie utile, soit en des vecteurs énergétiques solides, liquides ou gazeux. La gazéificationen particulier permet de générer un mélange de gaz combustibles qui peut être utilisé pour la production d’hydrogène ou d’hydrocarbures de synthèse linéaires. Ce procédé est présenté comme une des voies les plus intéressantes pour synthétiser des biocarburants de seconde génération. Cependant son développement est limité par la formation de goudrons contenus dans les gaz de gazéification qui abaissent les rendements et surtout désactivent les catalyseurs utilisés pour la synthèse des hydrocarbures ou de l’hydrogène. Une approche innovante consiste à introduire dans la biomasse des précurseurs de métaux connus pour leur activité catalytique pour le craquage de goudrons, afin qu’ils agissent dès la pyrolyse, qui est la pre...
Renewable & Sustainable Energy Reviews, 2011
This paper discusses the opportunity for substituting fossil fuels with biofuels in a Sahelian co... more This paper discusses the opportunity for substituting fossil fuels with biofuels in a Sahelian country, Burkina Faso. Bearing in mind the strong link between energy and development, and given the country's heavy reliance on imported fossil fuels, our study showed that the overall economy (private and public companies and basic social services) and the State Budget could be seriously affected
ChemInform, 2004
Using a CO 2 Laser. -Glass-like films of the title compound are synthesized by gas-phase decompos... more Using a CO 2 Laser. -Glass-like films of the title compound are synthesized by gas-phase decomposition of (tBuOAlH 2 ) 2 on metallic substrates heated to 240-250°C at 0.01-0.1 atm. The samples are characterized by powder XRD, IR, NMR MAS, and XPS spectroscopy. The HAlO layer, when heated to 450°C or when exposed to a CO 2 laser, transforms to an almost stoichiometric Al/Al 2 O 3 composite. Microstructures that are characterized by different chemical compositions and different optical contrasts of the "drawing", relative to the surrounding matrix, may be generated with an X/Y-table and a CO 2 laser. -(VEITH*, M.; ANDRES, K.; FABER, S.; BLIN, J.; ZIMMER, M.; WOLF, Y.; SCHNOECKEL, H.; KOEPPE, R.; DE MASI, R.; HUEFNER, S.; Eur.
Journal of Physical Chemistry C, 2013
ABSTRACT In order to promote process intensification in syngas production from biomass gasificati... more ABSTRACT In order to promote process intensification in syngas production from biomass gasification, our research team has already considered the integration of transition metal-based nanocatalysts in the biomass feedstock through its impregnation with metal salt aqueous solutions. The purpose of this work is to provide new insights into the complex physicochemical and catalytic mechanisms involved in this catalytic pathway from nickel salt. Applying a primary vacuum during impregnation allowed the rate of nickel insertion to be optimized and the generation of strong interactions between the metal cations and the lignocellulosic matrix. During biomass pyrolysis, Ni0 nanoparticles (NPs) form in situ below 500 °C through carbothermal reduction and provide the active sites for adsorption of aromatic hydrocarbons and subsequent catalytic conversion. In order to test whether it was possible to improve the catalytic efficiency of Ni0 NPs by making them available right from the pyrolysis onset, some preformed Ni0 NPs were inserted into the biomass prior to pyrolysis. The in situ generated Ni0 NPs exhibit higher catalytic efficiency, particularly for aromatic tar conversion, than preformed Ni0 NPs. The high decrease in hard-to-destroy aromatic hydrocarbons formation during pyrolysis is of particular interest in the overall gasification process. The proposed catalytic strategy reveals promising for simplifying the cleaning up of the producer gas.
Zeitschrift für anorganische und allgemeine Chemie, 2002
ABSTRACT
Renewable Energy, 2009
The need to decrease the consumption of materials and energy and to promote the use of renewable ... more The need to decrease the consumption of materials and energy and to promote the use of renewable resources, such as biofuels, stress the importance of evaluating the performance of engines based on the second law of thermodynamics. This paper suggests the use of exergy analysis (as an environmental assessment tool to account wastes and determine the exergy efficiency) combined with gas emissions analysis to optimize the performance of a compression ignition (CI) engine using biofuels such as cottonseed and palm oils, pure or blended with diesel for different engine loads. The results show that the combination of exergy and gas emissions analyses is a very effective tool for evaluating the optimal loads that can be supplied by CI engines. Taking into account technical constraints of engines, a tradeoff zone of engine loads (60% and 70% of the maximum load) was established between the gas emissions (NO and CO 2 ) and the exergy efficiency for optimal performance of the CI engine.
Renewable and Sustainable Energy Reviews, 2010
Ce document a vocation a presenter quelques elements d 'etat des lieux de la situation au Bur... more Ce document a vocation a presenter quelques elements d 'etat des lieux de la situation au Burkina Faso plutot qu'une analyse, en vue de faciliter les echanges et les comparaisons entre pays autour des enjeux et perspectives des biocarburants pour l'Afrique lors de la conference. Les themes abordes concernent le contexte general de l'agriculture, le contexte environnemental, le contexte energetique et le contexte des biocarburants. Les donnees sont quelquefois partielles mais seront completees apres la conference. Les principales sources statistiques et references bibliographiques utilisees sont listees en fin de document. (Resume d'auteur)
Journal of Renewable and Sustainable Energy, 2013
In West African countries, the objective of producer insertion in competitive markets is often as... more In West African countries, the objective of producer insertion in competitive markets is often associated with the need to modernize and mechanize production processes, i.e., replace labour by machines. This excludes traditional producers who can barely comply with the economic criteria but who must remain competitive to generate higher incomes. The challenge is to improve the efficiency of traditional methods in supply chains rather than imposing modern technologies that producers hardly adopt. Moreover, West African populations suffer from not having cheap and available energy sources. They, therefore, have to be imaginative for more efficient energy use in order to improve the productivity and quality of their products and support sustainable rural development and incomes. Building on the case study of the shea butter supply chain in Burkina Faso, this article proposes an original approach consisting of improved energy use for a more competitive and sustainable activity. The traditional butter production process consumes a great deal of energy from firewood and generates a lot of organic waste that could be used as an energy source. We examined the feasibility of using alternative energy techniques that could be taken on board as they are simple and designed from local resources, whilst using by-products from the shea butter production chain as biofuels to partially replace firewood. We showed that using alternative energy techniques, taken one by one or combined, can lead to lower energy use and thereby increase women's incomes, whilst helping to conserve forests. V C 2013 AIP Publishing LLC.
Renewable and Sustainable Energy Reviews, 2014
ABSTRACT The conversion of biomass by thermochemical means is very promising for the substitution... more ABSTRACT The conversion of biomass by thermochemical means is very promising for the substitution of fossil materials in many energy applications. Given the complexity of biomass the main challenge in its use is to obtain products with high yield and purity. For a better understanding of biomass thermochemical conversion, many authors have studied in TG analyzer or at bed scale the individual pyrolysis of its main constituents (i.e. cellulose, hemicelluloses and lignin). Based on these studies, this original work synthesizes the main steps of conversion and the composition of the products obtained from each constituent. Pyrolysis conversion can be described as the superposition of three main pathways (char formation, depolymerization and fragmentation) and secondary reactions. Lignin, which is composed of many benzene rings, gives the highest char yield and its depolymerization leads to various phenols. The depolymerization of the polysaccharides is a source of anhydro-saccharides and furan compounds. The fragmentation of the different constituents and the secondary reactions produce CO, CO2 and small chain compounds. For temperature higher than 500 °C, the residues obtained from the different constituents present a similar structure, which evolves towards a more condensed polyaromatic form by releasing CH4, CO and H2. As the aromatic rings and their substituent composition have a critical influence on the reactivity of pyrolysis products, a particular attention has been given to their formation. Some mechanisms are proposed to explain the formation of the main products. From the results of this study it is possible to predict the reactivity and energy content of the pyrolysis products and evaluate their potential use as biofuels in renewable applications.
Poor access to energy is now a key challenge to the development of many countries in the South. E... more Poor access to energy is now a key challenge to the development of many countries in the South. Energy supply has become a strategic priority for economic development policies, especially through developing renewable energies. In West Africa, more than 80 % of household energy is provided by biomass (firewood and charcoal). The challenge for developing countries is now moving from a domestic use of biomass energy to a modern use. The latter will help produce energy which remains essential to economic and social development. Indeed, despite their abundance on the African continent, many natural resources and raw materials are not valued and transformed into high value added products because of the lack of access to affordable power services. In 2004, biofuels aroused the enthusiasm of investors who invested on the sector while claiming their participation in the economic and social development of the continent. But in 2007, the rush for this green oil slowed down and the first review...
Renewable and Sustainable Energy Reviews, 2012
Biomass and Bioenergy, 2015
ABSTRACT In this work, we prepared iron- or nickel-impregnated cellulose to examine the influence... more ABSTRACT In this work, we prepared iron- or nickel-impregnated cellulose to examine the influence of the metal on the yield and composition of fast pyrolysis products. In order to identify the mechanisms promoted during the catalytic conversion, pyrolysis was investigated using an experimental set-up coupling TG (thermogravimetric) analysis and Micro-GC (Gas Chromatography). The results showed that with relatively low catalyst loading (mass fraction of 1.5% Fe or 1.7% Ni) impregnated metal can catalyze some rearrangement reactions such as dehydration and decarboxylation starting from 180 °C, promoting the char formation and thus inhibiting cellulose depolymerization. As a consequence metal impregnation led to a decrease of tar and CO yields balanced by an increase of char, H2O and CO2 yields. Depending on the applied metal, other primary reactions can be specifically catalyzed. In particular, in the presence of nickel TG analysis revealed an important mass loss at temperatures as low as 210 °C and an important increase of H2 production in the temperature range 400–500 °C. These findings open promising perspectives to optimize the production of fuels and chemicals from biomass.
Journal of the Chemical Society, Dalton Transactions, 1999
The lability of the SiO→M interaction unique to some bimetallic complexes may confer hemilabile p... more The lability of the SiO→M interaction unique to some bimetallic complexes may confer hemilabile properties to the Si(OR) 3 ligand and various bifunctional phosphines P-Z have been used in order to evaluate the possible competition for co-ordination between the bridging SiO→M interaction and P-Z chelation. Thus, treatment of the heterobimetallic complexes [(OC) 3 Fe{µ-Si(OMe) 2 (OMe)}(µ-dppm)MCl] (M = Pd 4 or Pt 6; dppm = Ph 2 PCH 2 PPh 2 ) and [(OC) 3 Fe{µ-Si(OMe) 2 (OMe)}(µ-dppa)PdCl] 5 (dppa = Ph 2 PNHPPh 2 ) with TlPF 6 in the presence of P-Z afforded the corresponding cationic compounds
Au Burkina Faso, les ressources énergétiques sont rares, et l’énergie importée coûte cher du fait... more Au Burkina Faso, les ressources énergétiques sont rares, et l’énergie importée coûte cher du fait de l’enclavement du pays. Dans ce contexte, le développement de la culture d’agrocarburants ne pourrait-elle pas être un levier pour le développement du pays et de son agriculture ?
ABSTRACT Présentation : L. VAN DE STEENE
Les filières de valorisation énergétique de la biomasse par voies thermochimiques présentent l’int... more Les filières de valorisation énergétique de la biomasse par voies thermochimiques présentent l’intérêt de pouvoir convertir toute matière ligno-cellulosique soit directement en énergie utile, soit en des vecteurs énergétiques solides, liquides ou gazeux. La gazéificationen particulier permet de générer un mélange de gaz combustibles qui peut être utilisé pour la production d’hydrogène ou d’hydrocarbures de synthèse linéaires. Ce procédé est présenté comme une des voies les plus intéressantes pour synthétiser des biocarburants de seconde génération. Cependant son développement est limité par la formation de goudrons contenus dans les gaz de gazéification qui abaissent les rendements et surtout désactivent les catalyseurs utilisés pour la synthèse des hydrocarbures ou de l’hydrogène. Une approche innovante consiste à introduire dans la biomasse des précurseurs de métaux connus pour leur activité catalytique pour le craquage de goudrons, afin qu’ils agissent dès la pyrolyse, qui est la pre...
Renewable & Sustainable Energy Reviews, 2011
This paper discusses the opportunity for substituting fossil fuels with biofuels in a Sahelian co... more This paper discusses the opportunity for substituting fossil fuels with biofuels in a Sahelian country, Burkina Faso. Bearing in mind the strong link between energy and development, and given the country's heavy reliance on imported fossil fuels, our study showed that the overall economy (private and public companies and basic social services) and the State Budget could be seriously affected
ChemInform, 2004
Using a CO 2 Laser. -Glass-like films of the title compound are synthesized by gas-phase decompos... more Using a CO 2 Laser. -Glass-like films of the title compound are synthesized by gas-phase decomposition of (tBuOAlH 2 ) 2 on metallic substrates heated to 240-250°C at 0.01-0.1 atm. The samples are characterized by powder XRD, IR, NMR MAS, and XPS spectroscopy. The HAlO layer, when heated to 450°C or when exposed to a CO 2 laser, transforms to an almost stoichiometric Al/Al 2 O 3 composite. Microstructures that are characterized by different chemical compositions and different optical contrasts of the "drawing", relative to the surrounding matrix, may be generated with an X/Y-table and a CO 2 laser. -(VEITH*, M.; ANDRES, K.; FABER, S.; BLIN, J.; ZIMMER, M.; WOLF, Y.; SCHNOECKEL, H.; KOEPPE, R.; DE MASI, R.; HUEFNER, S.; Eur.
Journal of Physical Chemistry C, 2013
ABSTRACT In order to promote process intensification in syngas production from biomass gasificati... more ABSTRACT In order to promote process intensification in syngas production from biomass gasification, our research team has already considered the integration of transition metal-based nanocatalysts in the biomass feedstock through its impregnation with metal salt aqueous solutions. The purpose of this work is to provide new insights into the complex physicochemical and catalytic mechanisms involved in this catalytic pathway from nickel salt. Applying a primary vacuum during impregnation allowed the rate of nickel insertion to be optimized and the generation of strong interactions between the metal cations and the lignocellulosic matrix. During biomass pyrolysis, Ni0 nanoparticles (NPs) form in situ below 500 °C through carbothermal reduction and provide the active sites for adsorption of aromatic hydrocarbons and subsequent catalytic conversion. In order to test whether it was possible to improve the catalytic efficiency of Ni0 NPs by making them available right from the pyrolysis onset, some preformed Ni0 NPs were inserted into the biomass prior to pyrolysis. The in situ generated Ni0 NPs exhibit higher catalytic efficiency, particularly for aromatic tar conversion, than preformed Ni0 NPs. The high decrease in hard-to-destroy aromatic hydrocarbons formation during pyrolysis is of particular interest in the overall gasification process. The proposed catalytic strategy reveals promising for simplifying the cleaning up of the producer gas.
Zeitschrift für anorganische und allgemeine Chemie, 2002
ABSTRACT
Renewable Energy, 2009
The need to decrease the consumption of materials and energy and to promote the use of renewable ... more The need to decrease the consumption of materials and energy and to promote the use of renewable resources, such as biofuels, stress the importance of evaluating the performance of engines based on the second law of thermodynamics. This paper suggests the use of exergy analysis (as an environmental assessment tool to account wastes and determine the exergy efficiency) combined with gas emissions analysis to optimize the performance of a compression ignition (CI) engine using biofuels such as cottonseed and palm oils, pure or blended with diesel for different engine loads. The results show that the combination of exergy and gas emissions analyses is a very effective tool for evaluating the optimal loads that can be supplied by CI engines. Taking into account technical constraints of engines, a tradeoff zone of engine loads (60% and 70% of the maximum load) was established between the gas emissions (NO and CO 2 ) and the exergy efficiency for optimal performance of the CI engine.
Renewable and Sustainable Energy Reviews, 2010