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Biodiesel production from canola in western australia / Ferry Rustandi in Industrial & engineering chemistry research, Vol. 49 N° 22 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11785–11796 Titre : Biodiesel production from canola in western australia : energy and carbon footprints and Land, water, and labour requirements Type de document : texte imprimé Auteurs : Ferry Rustandi, Auteur ; Hongwei Wu, Auteur Année de publication : 2011 Article en page(s) : pp. 11785–11796 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Biodiesel  Energy  Carbon Résumé : This study evaluates the energy and carbon footprints and land, water, and labor requirements of biodiesel production from canola in Western Australia (WA). The results show that canola-based biodiesel leads to limited energy profit and CO2 equivalent (CO2-e) emissions savings. Even when all byproduct are utilized, a relatively low output/input energy ratio of 1.72 and a CO2-e emissions savings of only 0.52 kg of CO2-e/L of biodiesel are obtained under the WA conditions considered in this study. A land requirement of 1.66 × 10−3 ha/L of biodiesel means that canola-based biodiesel seems to also be limited to <2% replacement of total diesel consumption in WA’s transport sector to avoid significant competition with food production for arable land. When some of the biodiesel is invested back into the production process to make the process independent of nonrenewable fuels, the competition for arable land use is even more severe, rendering it unfeasible to replace diesel fuel by the net biodiesel. Also, there would not be enough net biodiesel to support the transport activities that are usually supported by diesel fuel in the WA transport sector, and no CO2-e emissions savings would be achieved from replacing diesel fuel by net biodiesel. Overall, canola-based biodiesel is not sustainable to replace a significant fraction of diesel consumption in the WA transport sector. It can only play a limited role by offering some energy and CO2-e emissions savings and by providing immediate opportunities for introducing new transport fuels in the marketplace and developing familiarity among the consumers in our transition to a future sustainable biofuel supply. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1013162 [article] Biodiesel production from canola in western australia : energy and carbon footprints and Land, water, and labour requirements [texte imprimé] / Ferry Rustandi, Auteur ; Hongwei Wu, Auteur . - 2011 . - pp. 11785–11796. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 22 (Novembre 2010) . - pp. 11785–11796 Mots-clés : Biodiesel  Energy  Carbon Résumé : This study evaluates the energy and carbon footprints and land, water, and labor requirements of biodiesel production from canola in Western Australia (WA). The results show that canola-based biodiesel leads to limited energy profit and CO2 equivalent (CO2-e) emissions savings. Even when all byproduct are utilized, a relatively low output/input energy ratio of 1.72 and a CO2-e emissions savings of only 0.52 kg of CO2-e/L of biodiesel are obtained under the WA conditions considered in this study. A land requirement of 1.66 × 10−3 ha/L of biodiesel means that canola-based biodiesel seems to also be limited to <2% replacement of total diesel consumption in WA’s transport sector to avoid significant competition with food production for arable land. When some of the biodiesel is invested back into the production process to make the process independent of nonrenewable fuels, the competition for arable land use is even more severe, rendering it unfeasible to replace diesel fuel by the net biodiesel. Also, there would not be enough net biodiesel to support the transport activities that are usually supported by diesel fuel in the WA transport sector, and no CO2-e emissions savings would be achieved from replacing diesel fuel by net biodiesel. Overall, canola-based biodiesel is not sustainable to replace a significant fraction of diesel consumption in the WA transport sector. It can only play a limited role by offering some energy and CO2-e emissions savings and by providing immediate opportunities for introducing new transport fuels in the marketplace and developing familiarity among the consumers in our transition to a future sustainable biofuel supply. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1013162

Characteristics and precipitation of glucose oligomers in the fresh liquid products obtained from the hydrolysis of cellulose in hot-compressed water / Yun Yu in Industrial & engineering chemistry research, Vol. 48 N° 23 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10682–10690 Titre : Characteristics and precipitation of glucose oligomers in the fresh liquid products obtained from the hydrolysis of cellulose in hot-compressed water Type de document : texte imprimé Auteurs : Yun Yu, Auteur ; Hongwei Wu, Auteur Année de publication : 2010 Article en page(s) : pp. 10682–10690 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Characteristics--Precipitation--Glucose--Oligomers--Fresh  Liquid--Products--Obtained--Hydrolysis--Cellulose--Hot-Compressed--Water Résumé : Using a high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), this study shows the presence of a wide range of glucose oligomers with the degrees of polymerization (DPs) up to 30 and their derivatives in the fresh liquid products produced from cellulose hydrolysis in hot-compressed water (HCW) using a semicontinuous reactor system at 280 °C and 20 MPa. None of those oligomers can be detected by a high-performance liquid chromatography with evaporative light scattering detector (HPLC-ELSD) that however can detect glucose oligomers with DPs up to 6 after the liquid solutions are concentrated by 25 times via vacuum evaporation at 40 °C, during which a large amount of precipitate is formed. While quantitative analysis of the glucose oligomers with DPs > 5 cannot be done due to the lack of standards, that of the glucose oligomers from glucose (DP = 1) to cellopentaose (DP = 5) using both HPAEC-PAD and HPLC-ELSD are in good agreement, suggesting that these low-DP glucose oligomers do not contribute to the precipitate formation. Results from a set of purposely designed precipitation experiments indicate that the precipitation starts as the fresh liquid sample is collected and is fast during the initial 8 h, levels off as the precipitation time increases further, and completes after 120 h (5 days). On the basis of a new approach developed for the quantification of glucose oligomer retention during the precipitation process, it is found that the contribution of glucose oligomers to precipitate formation increases with DP. The higher the DP is, the lower the solubility of the glucose oligomer is. The glucose oligomers from glucose to cellopentaose and their derivatives (DPs = 1−5) contribute little to the precipitate formation, which explains why HPLC-ELSD can correctly analyze these glucose oligomers in the concentrated solutions prepared by vacuum evaporation. The glucose oligomers and their derivatives with DP > 5, which are soluble in HCW but become supersaturated in the solutions under ambient conditions, are responsible for precipitate formation. Most (but not all) of the glucose oligomers and their derivatives with DPs > 16 contribute to the precipitate formation as tiny peaks of these glucose oligomers are still shown in the chromatograms, suggesting that these glucose oligomers have very low (but nonzero) solubilities in ambient water. The retentions of glucose oligomers and their derivatives increase substantially with the DP decreasing from 16 to 6, indicating that less of these lower-DP oligomers contribute to the precipitate formation. To avoid the effect of precipitation on oligomer analysis, the fresh liquid products must be analyzed immediately after sample collection. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900768m [article] Characteristics and precipitation of glucose oligomers in the fresh liquid products obtained from the hydrolysis of cellulose in hot-compressed water [texte imprimé] / Yun Yu, Auteur ; Hongwei Wu, Auteur . - 2010 . - pp. 10682–10690. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10682–10690 Mots-clés : Characteristics--Precipitation--Glucose--Oligomers--Fresh  Liquid--Products--Obtained--Hydrolysis--Cellulose--Hot-Compressed--Water Résumé : Using a high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), this study shows the presence of a wide range of glucose oligomers with the degrees of polymerization (DPs) up to 30 and their derivatives in the fresh liquid products produced from cellulose hydrolysis in hot-compressed water (HCW) using a semicontinuous reactor system at 280 °C and 20 MPa. None of those oligomers can be detected by a high-performance liquid chromatography with evaporative light scattering detector (HPLC-ELSD) that however can detect glucose oligomers with DPs up to 6 after the liquid solutions are concentrated by 25 times via vacuum evaporation at 40 °C, during which a large amount of precipitate is formed. While quantitative analysis of the glucose oligomers with DPs > 5 cannot be done due to the lack of standards, that of the glucose oligomers from glucose (DP = 1) to cellopentaose (DP = 5) using both HPAEC-PAD and HPLC-ELSD are in good agreement, suggesting that these low-DP glucose oligomers do not contribute to the precipitate formation. Results from a set of purposely designed precipitation experiments indicate that the precipitation starts as the fresh liquid sample is collected and is fast during the initial 8 h, levels off as the precipitation time increases further, and completes after 120 h (5 days). On the basis of a new approach developed for the quantification of glucose oligomer retention during the precipitation process, it is found that the contribution of glucose oligomers to precipitate formation increases with DP. The higher the DP is, the lower the solubility of the glucose oligomer is. The glucose oligomers from glucose to cellopentaose and their derivatives (DPs = 1−5) contribute little to the precipitate formation, which explains why HPLC-ELSD can correctly analyze these glucose oligomers in the concentrated solutions prepared by vacuum evaporation. The glucose oligomers and their derivatives with DP > 5, which are soluble in HCW but become supersaturated in the solutions under ambient conditions, are responsible for precipitate formation. Most (but not all) of the glucose oligomers and their derivatives with DPs > 16 contribute to the precipitate formation as tiny peaks of these glucose oligomers are still shown in the chromatograms, suggesting that these glucose oligomers have very low (but nonzero) solubilities in ambient water. The retentions of glucose oligomers and their derivatives increase substantially with the DP decreasing from 16 to 6, indicating that less of these lower-DP oligomers contribute to the precipitate formation. To avoid the effect of precipitation on oligomer analysis, the fresh liquid products must be analyzed immediately after sample collection. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900768m

Effect of hydrodistillation on 1,8 - cineole extraction from mallee leal and the fuel properties of spent biomass / Hongwei Wu in Industrial & engineering chemistry research, Vol. 50 N° 19 (Octobre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 19 (Octobre 2011) . - pp. 11280-11287 Titre : Effect of hydrodistillation on 1,8 - cineole extraction from mallee leal and the fuel properties of spent biomass Type de document : texte imprimé Auteurs : Hongwei Wu, Auteur ; William Hendrawinata, Auteur ; Yun Yu, Auteur Année de publication : 2011 Article en page(s) : pp. 11280-11287 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Biomass  Fuel Résumé : Many mallee eucalyptus species have leaves that contain terpenoid oils commonly known as eucalyptus oil, of which 1,8-cineole is the major constituent. 1,8-Cineole is potentially a high-value product that might improve the economic viability of a mallee-based biomass industry. It can be extracted by hydrodistillation, but the extraction process may affect the fuel properties of spent biomass. It was found that extraction of 1,8-cineole from mallee biomass is fast initially and tapers off to completion after 30 min of hydrodistillation. The distillation process has little effect on the fuel chemistry or the mass energy density of the spent biomass. However, hydrodistillation can potentially extract a substantial proportion of the alkali and alkaline earth metallic species from the raw biomass, depending on the biomass component (leaf, wood, and bark). Typically, Na and K are easily extracted while Mg and Ca are hard to extract. After hydrodistillation, the spent leaf becomes more difficult to grind than the raw leaf, apparently because ofthe poorer grindiability ofthe oil gland enclosures and vascular bundles after hydrodistillation. However, hydrodistillation appears to have little effect on the grindability of spent wood and bark fractions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24573325 [article] Effect of hydrodistillation on 1,8 - cineole extraction from mallee leal and the fuel properties of spent biomass [texte imprimé] / Hongwei Wu, Auteur ; William Hendrawinata, Auteur ; Yun Yu, Auteur . - 2011 . - pp. 11280-11287. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 19 (Octobre 2011) . - pp. 11280-11287 Mots-clés : Biomass  Fuel Résumé : Many mallee eucalyptus species have leaves that contain terpenoid oils commonly known as eucalyptus oil, of which 1,8-cineole is the major constituent. 1,8-Cineole is potentially a high-value product that might improve the economic viability of a mallee-based biomass industry. It can be extracted by hydrodistillation, but the extraction process may affect the fuel properties of spent biomass. It was found that extraction of 1,8-cineole from mallee biomass is fast initially and tapers off to completion after 30 min of hydrodistillation. The distillation process has little effect on the fuel chemistry or the mass energy density of the spent biomass. However, hydrodistillation can potentially extract a substantial proportion of the alkali and alkaline earth metallic species from the raw biomass, depending on the biomass component (leaf, wood, and bark). Typically, Na and K are easily extracted while Mg and Ca are hard to extract. After hydrodistillation, the spent leaf becomes more difficult to grind than the raw leaf, apparently because ofthe poorer grindiability ofthe oil gland enclosures and vascular bundles after hydrodistillation. However, hydrodistillation appears to have little effect on the grindability of spent wood and bark fractions. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24573325

Evolution of char structure during the steam gasification of biochars produced from the pyrolysis of various mallee biomass components / Hongwei Wu in Industrial & engineering chemistry research, Vol. 48 N° 23 (Décembre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10431–10438 Titre : Evolution of char structure during the steam gasification of biochars produced from the pyrolysis of various mallee biomass components Type de document : texte imprimé Auteurs : Hongwei Wu, Auteur ; Kongvui Yip, Auteur ; Fujun Tian, Auteur Année de publication : 2010 Article en page(s) : pp. 10431–10438 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Evolution--Structure--during--Steam--Gasification--Biochars--Produced--Pyrolysis--Various--Mallee--Biomass--Components Résumé : This study reports the evolution of char structure during the steam gasification of biochars under chemical-reaction-controlled conditions. Partially gasified samples were collected at various conversion levels during the steam gasification of both the raw biochars and the acid-treated biochars that had been prepared via acid-washing of the raw biochars. Results from FT-Raman spectroscopy show that the biochars have highly heterogeneous and disordered structures, which are selectively consumed with progress of steam gasification, leading to enrichment of larger aromatic ring systems, hence the so-called “selective gasification”. Selective gasification of biochar can be significantly influenced by the inherent alkali and alkaline earth metallic (AAEM) species in the biochars. The abundant catalysts present in the raw biochars can alter the gasification reaction pathway, but such an alteration appears to have little effect on the evolution of pore surface area, which increases significantly with conversion. While the wood biochar has too low a content of AAEM species to have an apparent effect on selective gasification, for the raw leaf and bark biochars with high contents of AAEM species, selective gasification is considerably less significant in comparison with the respective acid-treated biochars. For acid-treated biochars, gasification seems to take place slowly throughout the biochar on carbon active sites to consume the smaller rings selectively; the reactivity is controlled by the biochar carbon structure. However, for the raw leaf and bark biochars, gasification would be more focused or localized on the catalytic sites so that the activity of carbon active sites becomes less important. The catalytic effect of the inherent AAEM species seems to in turn depend on the carbon structure that probably affects the catalyst dispersion. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901025d [article] Evolution of char structure during the steam gasification of biochars produced from the pyrolysis of various mallee biomass components [texte imprimé] / Hongwei Wu, Auteur ; Kongvui Yip, Auteur ; Fujun Tian, Auteur . - 2010 . - pp. 10431–10438. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 23 (Décembre 2009) . - pp. 10431–10438 Mots-clés : Evolution--Structure--during--Steam--Gasification--Biochars--Produced--Pyrolysis--Various--Mallee--Biomass--Components Résumé : This study reports the evolution of char structure during the steam gasification of biochars under chemical-reaction-controlled conditions. Partially gasified samples were collected at various conversion levels during the steam gasification of both the raw biochars and the acid-treated biochars that had been prepared via acid-washing of the raw biochars. Results from FT-Raman spectroscopy show that the biochars have highly heterogeneous and disordered structures, which are selectively consumed with progress of steam gasification, leading to enrichment of larger aromatic ring systems, hence the so-called “selective gasification”. Selective gasification of biochar can be significantly influenced by the inherent alkali and alkaline earth metallic (AAEM) species in the biochars. The abundant catalysts present in the raw biochars can alter the gasification reaction pathway, but such an alteration appears to have little effect on the evolution of pore surface area, which increases significantly with conversion. While the wood biochar has too low a content of AAEM species to have an apparent effect on selective gasification, for the raw leaf and bark biochars with high contents of AAEM species, selective gasification is considerably less significant in comparison with the respective acid-treated biochars. For acid-treated biochars, gasification seems to take place slowly throughout the biochar on carbon active sites to consume the smaller rings selectively; the reactivity is controlled by the biochar carbon structure. However, for the raw leaf and bark biochars, gasification would be more focused or localized on the catalytic sites so that the activity of carbon active sites becomes less important. The catalytic effect of the inherent AAEM species seems to in turn depend on the carbon structure that probably affects the catalyst dispersion. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901025d

Evolution of primary liquid products and evidence of in situ structural changes in cellulose with conversion during hydrolysis in hot-compressed water / Yun Yu in Industrial & engineering chemistry research, Vol. 49 N° 8 (Avril 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 8 (Avril 2010) . - pp. 3919–3925 Titre : Evolution of primary liquid products and evidence of in situ structural changes in cellulose with conversion during hydrolysis in hot-compressed water Type de document : texte imprimé Auteurs : Yun Yu, Auteur ; Hongwei Wu, Auteur Année de publication : 2010 Article en page(s) : pp. 3919–3925 Note générale : Industrial Chemistry Langues : Anglais (eng) Mots-clés : Liquid  Evidence  Cellulose  Hydrolysis  Hot-Compressed  Water Résumé : This study shows the dynamic evolution of the primary liquid products with conversion during the hydrolysis of both amorphous and crystalline cellulose in hot-compressed water (HCW). The results suggest that the dynamic changes in cellulose structure occur during conversion and strongly depend on reaction temperature. Results from a set of purposely designed two-step experiments further confirm at least two mechanisms which may be responsible for such structural changes. One is the selective consumption of the reactive components within the intrinsically heterogeneous cellulose at early conversions. This mechanism dominates during the hydrolysis of at low temperatures, e.g., 180−200 °C for amorphous cellulose and 230 °C for microcrystalline cellulose. The other is the combined effects of various parallel reactions during hydrolysis in HCW, including cleavage of hydrogen bonds, degradation reactions, and cross-linking reactions. Enhanced hydrogen bond cleavage increases the production of glucose oligomers. However, parallel degradation reactions and cross-linking reactions decrease the selectivity of glucose oligomers. The effect of cross-linking of cellulose in HCW appears to increase with temperature and becomes significant at 270 °C, leading to a structural condensation and hence a reduction in the specific reactivity of cellulose and the selectivity of glucose oligomers in the primary liquid products. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902020t [article] Evolution of primary liquid products and evidence of in situ structural changes in cellulose with conversion during hydrolysis in hot-compressed water [texte imprimé] / Yun Yu, Auteur ; Hongwei Wu, Auteur . - 2010 . - pp. 3919–3925. Industrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 8 (Avril 2010) . - pp. 3919–3925 Mots-clés : Liquid  Evidence  Cellulose  Hydrolysis  Hot-Compressed  Water Résumé : This study shows the dynamic evolution of the primary liquid products with conversion during the hydrolysis of both amorphous and crystalline cellulose in hot-compressed water (HCW). The results suggest that the dynamic changes in cellulose structure occur during conversion and strongly depend on reaction temperature. Results from a set of purposely designed two-step experiments further confirm at least two mechanisms which may be responsible for such structural changes. One is the selective consumption of the reactive components within the intrinsically heterogeneous cellulose at early conversions. This mechanism dominates during the hydrolysis of at low temperatures, e.g., 180−200 °C for amorphous cellulose and 230 °C for microcrystalline cellulose. The other is the combined effects of various parallel reactions during hydrolysis in HCW, including cleavage of hydrogen bonds, degradation reactions, and cross-linking reactions. Enhanced hydrogen bond cleavage increases the production of glucose oligomers. However, parallel degradation reactions and cross-linking reactions decrease the selectivity of glucose oligomers. The effect of cross-linking of cellulose in HCW appears to increase with temperature and becomes significant at 270 °C, leading to a structural condensation and hence a reduction in the specific reactivity of cellulose and the selectivity of glucose oligomers in the primary liquid products. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie902020t

Kinetics and mechanism of glucose decomposition in hot-compressed water / Yun Yu in Industrial & engineering chemistry research, Vol. 50 N° 18 (Septembre 2011) 

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Removal and recycling of inherent inorganic nutrient species in mallee biomass and derived biochars by water leaching / Hongwei Wu in Industrial & engineering chemistry research, Vol. 50 N° 21 (Novembre 2011) 

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Significant differences in the hydrolysis behavior of amorphous and crystalline portions within microcrystalline cellulose in hot-compressed water / Yun Yu in Industrial & engineering chemistry research, Vol. 49 N° 8 (Avril 2010) 

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