The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
Geert-jan Witkamp - One of the best experts on this subject based on the ideXlab platform.
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Mechanical action in CO2 dry cleaning
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, M. J E Van Roosmalen, Geert-jan WitkampAbstract:High-pressure carbon dioxide (CO2) is a potential alternative for perchloroethylene (PER), a common but harmful textile dry cleaning solvent. Previous studies have indicated that the Particulate Soil removal with CO2 is lower compared to that with PER, because of the low amount of mechanical action in CO2. It is the objective of this study to get more insight in the influence of various types of mechanical action on the cleaning results in CO2 dry cleaning. In the experiments, various mechanisms of mechanical action, such as rotating drum, CO2 spray, and ultrasound were investigated. Several types of textiles stained with different kinds of Particulate Soils were cleaned using 25 L and 90 L CO2 dry cleaning set-ups. The washing results show that liquid CO2 spray may be a suitable additional mechanism to provide textile movement. The average CPI of CO2 over all Soils using the best combination of commercial machine and process was still 25% lower than the results with PER and 18% lower than the results with water, but 11% higher than K4 solvent while the average redeposition level was significantly lower, showing that CO2 has a good prospect as an alternative solvent to replace PER. An endoscopic camera has been installed in the 25 L set-up to get an insight in the textile movement inside the rotating drum. The results show that no plug formation occurs and the textile movement in CO2 is sluggish, which means that the mechanical movement of textile in CO2 dry cleaning does not follow the simplified tumbling-movement model which was developed in a previous study, and the mechanical action is much less than predicted.
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CO2 dry cleaning: Acoustic cavitation and other mechanisms to induce mechanical action
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, M. J E Van Roosmalen, Victoria Dutschk, Johannes Mankiewicz, Marijn M C G Warmoeskerken, Geert-jan WitkampAbstract:High pressure carbon dioxide (CO2) is a potential solvent for textile dry cleaning. However, the Particulate Soil (e.g. clay, sand) removal in CO2 is generally insufficient. Since cavitation has been proven to be beneficial in other CO2 cleaning applications, this study aims to investigate the possibility of improving the performance of CO2 textile dry cleaning by using ultrasound or other mechanisms to induce the mechanical action such as bubble spray and jet spray. In the experiments, several types of textiles Soiled with a mixture of motor oil and soot were cleaned using 1 L and 90 L CO2 dry cleaning set-ups. Using either ultrasound, stirring, liquid spray or bubble spray does not give a significant improvement on Particulate Soil removal from textile. It was also found that the additional use of ClipCOO detergent does not give a significant improvement on Particulate Soil removal either. The cleaning performance of CO2 is 50% lower than that of PER and thus another method to increase the Particulate Soil removal in CO2 textile dry cleaning still needs to be developed. ?? 2014 Elsevier B.V.
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Redeposition in CO2 textile dry cleaning
Journal of Supercritical Fluids, 2013Co-Authors: Stevia Sutanto, M J E Van Roosmalen, Geert-jan WitkampAbstract:Abstract Perchloroethylene (PER) is commonly used as cleaning solvent in the textile dry-cleaning industry but this chemical is toxic by nature. One of the potential PER replacements is carbon dioxide (CO2), which is non-toxic, cheap, and widely available. Previous studies have indicated that the Particulate Soil removal with CO2 is lower compared to that of PER. While the Particulate Soil removal of the CO2 dry-cleaning was studied, it was found that redeposition of Particulate Soil occurs. Several experiments have been carried out to study and reduce this problem. In these experiments, textiles stained with different kinds of Particulate Soils were cleaned using a 25 L CO2 dry-cleaning set-up. It was found that the redeposition level increases along with washing time, while rinsing has little influence. Modifying the filtration system by using scavenger textile, or adding a cellulose compound to the cleaning vessel as anti redeposition agent can significantly reduce redeposition.
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Amino acid based surfactants for dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:Abstract The currently most used dry-cleaning solvent is perchloroethylene (PER). Carbon dioxide could be an ideal solvent to replace PER. Amino acid based surfactants have been studied for dry-cleaning with carbon dioxide. For the production of amino acid based surfactants, renewable, low-cost raw materials are used. Furthermore, these surfactants have a low toxicity, are biodegradable and not skin irritating. These characteristics make the amino acid based surfactants attractive for dry-cleaning with carbon dioxide. The amino acid based surfactants give good results for dry-cleaning with liquid CO2. The surfactant Amihope LL (N-lauroyl- l -lysine) gives the best cleaning-results. An important process parameter using this surfactant is the addition of water. The addition of water is required for sufficient removal of non-Particulate Soils. However, when no water is added to the system, there is a large increase in Particulate Soil removal. Therefore, a two-bath process is proposed. The first bath is for Particulate Soil removal and has optimal conditions for Particulate Soil removal; the second bath has optimal conditions for non-Particulate Soil removal. The two-bath process using Amihope LL gives excellent results: the result for Particulate Soil removal is 84% compared to the results for PER, the result for non-Particulate Soil removal is 98% compared to PER and the overall result is 92% compared to PER.
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surfactants for Particulate Soil removal in dry cleaning with high pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The removal of Particulate Soils from textile in dry-cleaning with CO2 is insufficient compared to perchloroethylene (PER). Especially the removal of relatively small particles (<20 μm) poses a problem. Various anionic and amine based surfactants have been investigated to enhance the removal of Particulate, but also of non-Particulate Soils in dry-cleaning with high-pressure CO2. The cleaning performance index for relatively small Particulate Soil (CPIpart) increased from 24% (when no surfactants were used) to a maximum of 51% (when surfactants were used), which shows that particle removal is possible in CO2 dry-cleaning. The use of these surfactants, however, does not bring particle removal up to the level of PER (CPIpart of 68%). The removal of non-Particulate Soils in CO2 with water, surfactant and co-solvent is better than in PER. The overall results using the investigated surfactants are promising; the overall result increases from 70% (when no surfactants are used) to 87% (when surfactants are used) compared to the level when using PER. Surfactant particles were formed in all experiments. In the case of the amines, these particles may be formed by reaction. The formed charged surfactant particles are probably responsible for the removal of the Soil particles from the textile. The charged surfactant particles may adhere to the Soil particles and/or fabric, thereby establishing an element of repulsion and/or a steric barrier. The use of a co-solvent (iso-propanol) had a positive effect on the removal of Particulate and non-Particulate Soils when using amines. However, when anionic surfactants were used, the addition of a co-solvent had a pronounced negative effect on Particulate Soil removal.
M. J E Van Roosmalen - One of the best experts on this subject based on the ideXlab platform.
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Mechanical action in CO2 dry cleaning
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, M. J E Van Roosmalen, Geert-jan WitkampAbstract:High-pressure carbon dioxide (CO2) is a potential alternative for perchloroethylene (PER), a common but harmful textile dry cleaning solvent. Previous studies have indicated that the Particulate Soil removal with CO2 is lower compared to that with PER, because of the low amount of mechanical action in CO2. It is the objective of this study to get more insight in the influence of various types of mechanical action on the cleaning results in CO2 dry cleaning. In the experiments, various mechanisms of mechanical action, such as rotating drum, CO2 spray, and ultrasound were investigated. Several types of textiles stained with different kinds of Particulate Soils were cleaned using 25 L and 90 L CO2 dry cleaning set-ups. The washing results show that liquid CO2 spray may be a suitable additional mechanism to provide textile movement. The average CPI of CO2 over all Soils using the best combination of commercial machine and process was still 25% lower than the results with PER and 18% lower than the results with water, but 11% higher than K4 solvent while the average redeposition level was significantly lower, showing that CO2 has a good prospect as an alternative solvent to replace PER. An endoscopic camera has been installed in the 25 L set-up to get an insight in the textile movement inside the rotating drum. The results show that no plug formation occurs and the textile movement in CO2 is sluggish, which means that the mechanical movement of textile in CO2 dry cleaning does not follow the simplified tumbling-movement model which was developed in a previous study, and the mechanical action is much less than predicted.
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CO2 dry cleaning: Acoustic cavitation and other mechanisms to induce mechanical action
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, M. J E Van Roosmalen, Victoria Dutschk, Johannes Mankiewicz, Marijn M C G Warmoeskerken, Geert-jan WitkampAbstract:High pressure carbon dioxide (CO2) is a potential solvent for textile dry cleaning. However, the Particulate Soil (e.g. clay, sand) removal in CO2 is generally insufficient. Since cavitation has been proven to be beneficial in other CO2 cleaning applications, this study aims to investigate the possibility of improving the performance of CO2 textile dry cleaning by using ultrasound or other mechanisms to induce the mechanical action such as bubble spray and jet spray. In the experiments, several types of textiles Soiled with a mixture of motor oil and soot were cleaned using 1 L and 90 L CO2 dry cleaning set-ups. Using either ultrasound, stirring, liquid spray or bubble spray does not give a significant improvement on Particulate Soil removal from textile. It was also found that the additional use of ClipCOO detergent does not give a significant improvement on Particulate Soil removal either. The cleaning performance of CO2 is 50% lower than that of PER and thus another method to increase the Particulate Soil removal in CO2 textile dry cleaning still needs to be developed. ?? 2014 Elsevier B.V.
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Amino acid based surfactants for dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M. J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The currently most used dry-cleaning solvent is perchloroethylene (PER). Carbon dioxide could be an ideal solvent to replace PER. Amino acid based surfactants have been studied for dry-cleaning with carbon dioxide. For the production of amino acid based surfactants, renewable, low-cost raw materials are used. Furthermore, these surfactants have a low toxicity, are biodegradable and not skin irritating. These characteristics make the amino acid based surfactants attractive for dry-cleaning with carbon dioxide. The amino acid based surfactants give good results for dry-cleaning with liquid CO2. The surfactant Amihope LL (N-lauroyl-L-lysine) gives the best cleaning-results. An important process parameter using this surfactant is the addition of water. The addition of water is required for sufficient removal of non-Particulate Soils. However, when no water is added to the system, there is a large increase in Particulate Soil removal. Therefore, a two-bath process is proposed. The first bath is for Particulate Soil removal and has optimal conditions for Particulate Soil removal; the second bath has optimal conditions for non-Particulate Soil removal. The two-bath process using Amihope LL gives excellent results: the result for Particulate Soil removal is 84% compared to the results for PER, the result for non-Particulate Soil removal is 98% compared to PER and the overall result is 92% compared to PER. ?? 2004 Elsevier B.V. All rights reserved.
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Surfactants for Particulate Soil removal in dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M. J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The removal of Particulate Soils from textile in dry-cleaning with CO 2 is insufficient compared to perchloroethylene (PER). Especially the removal of relatively small particles (
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Dry-cleaning with high-pressure carbon dioxide - The influence of mechanical action on washing-results
Journal of Supercritical Fluids, 2003Co-Authors: M. J E Van Roosmalen, M. Van Diggelen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:Previous studies indicate that the removal of non-polar Soils in CO 2 is comparable to the level of dry-cleaning in perchloroethylene (PER). However, these studies show that the removal of Particulate Soil is insufficient in CO2 compared to PER. Particle removal can be increased by the use of more mechanical action and/or the use of surfactants. From experiments, it is concluded that the removal of relatively large particles like sand increases with increasing mechanical action. However, the level of mechanical action has no influence on the removal of relatively small Particulate and non-Particulate Soils (with the exception of clay on wool). Increasing the amount of mechanical action is therefore not the solution that will lead to the increase of the washing-results for relatively small particles (like carbon black and clay) up to the level of the washing-results using PER. The removal of relatively small Particulate Soils in CO2 can be improved by the use of suitable surfactants that reduce adhesion forces. A model for quantifying the amount of mechanical action has been developed. This model can be used to predict the optimal process conditions for relatively large particle removal. It is concluded (from the model and experiments) that the level of highest mechanical action in CO2 is obtained in a two-phase environment at low pressure and temperature and that 75 RPM is the optimal number of revolutions in our system. At these conditions, however, the washing-results for small particles are not as good as the washing-results for these particles in PER. ?? 2002 Elsevier Science B.V. All rights reserved.
GREERT FEYE WOERLEE - One of the best experts on this subject based on the ideXlab platform.
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Amino acid based surfactants for dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:Abstract The currently most used dry-cleaning solvent is perchloroethylene (PER). Carbon dioxide could be an ideal solvent to replace PER. Amino acid based surfactants have been studied for dry-cleaning with carbon dioxide. For the production of amino acid based surfactants, renewable, low-cost raw materials are used. Furthermore, these surfactants have a low toxicity, are biodegradable and not skin irritating. These characteristics make the amino acid based surfactants attractive for dry-cleaning with carbon dioxide. The amino acid based surfactants give good results for dry-cleaning with liquid CO2. The surfactant Amihope LL (N-lauroyl- l -lysine) gives the best cleaning-results. An important process parameter using this surfactant is the addition of water. The addition of water is required for sufficient removal of non-Particulate Soils. However, when no water is added to the system, there is a large increase in Particulate Soil removal. Therefore, a two-bath process is proposed. The first bath is for Particulate Soil removal and has optimal conditions for Particulate Soil removal; the second bath has optimal conditions for non-Particulate Soil removal. The two-bath process using Amihope LL gives excellent results: the result for Particulate Soil removal is 84% compared to the results for PER, the result for non-Particulate Soil removal is 98% compared to PER and the overall result is 92% compared to PER.
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surfactants for Particulate Soil removal in dry cleaning with high pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The removal of Particulate Soils from textile in dry-cleaning with CO2 is insufficient compared to perchloroethylene (PER). Especially the removal of relatively small particles (<20 μm) poses a problem. Various anionic and amine based surfactants have been investigated to enhance the removal of Particulate, but also of non-Particulate Soils in dry-cleaning with high-pressure CO2. The cleaning performance index for relatively small Particulate Soil (CPIpart) increased from 24% (when no surfactants were used) to a maximum of 51% (when surfactants were used), which shows that particle removal is possible in CO2 dry-cleaning. The use of these surfactants, however, does not bring particle removal up to the level of PER (CPIpart of 68%). The removal of non-Particulate Soils in CO2 with water, surfactant and co-solvent is better than in PER. The overall results using the investigated surfactants are promising; the overall result increases from 70% (when no surfactants are used) to 87% (when surfactants are used) compared to the level when using PER. Surfactant particles were formed in all experiments. In the case of the amines, these particles may be formed by reaction. The formed charged surfactant particles are probably responsible for the removal of the Soil particles from the textile. The charged surfactant particles may adhere to the Soil particles and/or fabric, thereby establishing an element of repulsion and/or a steric barrier. The use of a co-solvent (iso-propanol) had a positive effect on the removal of Particulate and non-Particulate Soils when using amines. However, when anionic surfactants were used, the addition of a co-solvent had a pronounced negative effect on Particulate Soil removal.
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Amino acid based surfactants for dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M. J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The currently most used dry-cleaning solvent is perchloroethylene (PER). Carbon dioxide could be an ideal solvent to replace PER. Amino acid based surfactants have been studied for dry-cleaning with carbon dioxide. For the production of amino acid based surfactants, renewable, low-cost raw materials are used. Furthermore, these surfactants have a low toxicity, are biodegradable and not skin irritating. These characteristics make the amino acid based surfactants attractive for dry-cleaning with carbon dioxide. The amino acid based surfactants give good results for dry-cleaning with liquid CO2. The surfactant Amihope LL (N-lauroyl-L-lysine) gives the best cleaning-results. An important process parameter using this surfactant is the addition of water. The addition of water is required for sufficient removal of non-Particulate Soils. However, when no water is added to the system, there is a large increase in Particulate Soil removal. Therefore, a two-bath process is proposed. The first bath is for Particulate Soil removal and has optimal conditions for Particulate Soil removal; the second bath has optimal conditions for non-Particulate Soil removal. The two-bath process using Amihope LL gives excellent results: the result for Particulate Soil removal is 84% compared to the results for PER, the result for non-Particulate Soil removal is 98% compared to PER and the overall result is 92% compared to PER. ?? 2004 Elsevier B.V. All rights reserved.
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Surfactants for Particulate Soil removal in dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M. J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The removal of Particulate Soils from textile in dry-cleaning with CO 2 is insufficient compared to perchloroethylene (PER). Especially the removal of relatively small particles (
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Dry-cleaning with high-pressure carbon dioxide—the influence of mechanical action on washing-results
Journal of Supercritical Fluids, 2003Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, M. Van Diggelen, Geert-jan WitkampAbstract:Abstract Previous studies indicate that the removal of non-polar Soils in CO2 is comparable to the level of dry-cleaning in perchloroethylene (PER). However, these studies show that the removal of Particulate Soil is insufficient in CO2 compared to PER. Particle removal can be increased by the use of more mechanical action and/or the use of surfactants. From experiments, it is concluded that the removal of relatively large particles like sand increases with increasing mechanical action. However, the level of mechanical action has no influence on the removal of relatively small Particulate and non-Particulate Soils (with the exception of clay on wool). Increasing the amount of mechanical action is therefore not the solution that will lead to the increase of the washing-results for relatively small particles (like carbon black and clay) up to the level of the washing-results using PER. The removal of relatively small Particulate Soils in CO2 can be improved by the use of suitable surfactants that reduce adhesion forces. A model for quantifying the amount of mechanical action has been developed. This model can be used to predict the optimal process conditions for relatively large particle removal. It is concluded (from the model and experiments) that the level of highest mechanical action in CO2 is obtained in a two-phase environment at low pressure and temperature and that 75 RPM is the optimal number of revolutions in our system. At these conditions, however, the washing-results for small particles are not as good as the washing-results for these particles in PER.
Stevia Sutanto - One of the best experts on this subject based on the ideXlab platform.
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CO2 dry cleaning: Acoustic cavitation and other mechanisms to induce mechanical action
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, Victoria Dutschk, Johannes Mankiewicz, M. Van Roosmaalen, Marijn M C G WarmoeskerkenAbstract:High pressure carbon dioxide (CO2) is a potential solvent for textile dry cleaning. However, the Particulate Soil (e.g. clay, sand) removal in CO2 is generally insufficient. Since cavitation has been proven to be beneficial in other CO2 cleaning applications, this study aims to investigate the possibility of improving the performance of CO2 textile dry cleaning by using ultrasound or other mechanisms to induce the mechanical action such as bubble spray and jet spray. In the experiments, several types of textiles Soiled with a mixture of motor oil and soot were cleaned using 1 Land 90 L CO2 dry cleaning set-ups. Using either ultrasound, stirring, liquid spray or bubble spray does not give a significant improvement on Particulate Soil removal from textile. It was also found that the additional use of ClipCOO detergent does not give a significant improvement on Particulate Soil removal either. The cleaning performance of CO2 is 50% lower than that of PER and thus another method to increase the Particulate Soil removal in CO2 textile dry cleaning still needs to be developed.
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Mechanical action in CO2 dry cleaning
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, M. J E Van Roosmalen, Geert-jan WitkampAbstract:High-pressure carbon dioxide (CO2) is a potential alternative for perchloroethylene (PER), a common but harmful textile dry cleaning solvent. Previous studies have indicated that the Particulate Soil removal with CO2 is lower compared to that with PER, because of the low amount of mechanical action in CO2. It is the objective of this study to get more insight in the influence of various types of mechanical action on the cleaning results in CO2 dry cleaning. In the experiments, various mechanisms of mechanical action, such as rotating drum, CO2 spray, and ultrasound were investigated. Several types of textiles stained with different kinds of Particulate Soils were cleaned using 25 L and 90 L CO2 dry cleaning set-ups. The washing results show that liquid CO2 spray may be a suitable additional mechanism to provide textile movement. The average CPI of CO2 over all Soils using the best combination of commercial machine and process was still 25% lower than the results with PER and 18% lower than the results with water, but 11% higher than K4 solvent while the average redeposition level was significantly lower, showing that CO2 has a good prospect as an alternative solvent to replace PER. An endoscopic camera has been installed in the 25 L set-up to get an insight in the textile movement inside the rotating drum. The results show that no plug formation occurs and the textile movement in CO2 is sluggish, which means that the mechanical movement of textile in CO2 dry cleaning does not follow the simplified tumbling-movement model which was developed in a previous study, and the mechanical action is much less than predicted.
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CO2 dry cleaning: Acoustic cavitation and other mechanisms to induce mechanical action
Journal of Supercritical Fluids, 2014Co-Authors: Stevia Sutanto, M. J E Van Roosmalen, Victoria Dutschk, Johannes Mankiewicz, Marijn M C G Warmoeskerken, Geert-jan WitkampAbstract:High pressure carbon dioxide (CO2) is a potential solvent for textile dry cleaning. However, the Particulate Soil (e.g. clay, sand) removal in CO2 is generally insufficient. Since cavitation has been proven to be beneficial in other CO2 cleaning applications, this study aims to investigate the possibility of improving the performance of CO2 textile dry cleaning by using ultrasound or other mechanisms to induce the mechanical action such as bubble spray and jet spray. In the experiments, several types of textiles Soiled with a mixture of motor oil and soot were cleaned using 1 L and 90 L CO2 dry cleaning set-ups. Using either ultrasound, stirring, liquid spray or bubble spray does not give a significant improvement on Particulate Soil removal from textile. It was also found that the additional use of ClipCOO detergent does not give a significant improvement on Particulate Soil removal either. The cleaning performance of CO2 is 50% lower than that of PER and thus another method to increase the Particulate Soil removal in CO2 textile dry cleaning still needs to be developed. ?? 2014 Elsevier B.V.
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Redeposition in CO2 textile dry cleaning
Journal of Supercritical Fluids, 2013Co-Authors: Stevia Sutanto, M J E Van Roosmalen, Geert-jan WitkampAbstract:Abstract Perchloroethylene (PER) is commonly used as cleaning solvent in the textile dry-cleaning industry but this chemical is toxic by nature. One of the potential PER replacements is carbon dioxide (CO2), which is non-toxic, cheap, and widely available. Previous studies have indicated that the Particulate Soil removal with CO2 is lower compared to that of PER. While the Particulate Soil removal of the CO2 dry-cleaning was studied, it was found that redeposition of Particulate Soil occurs. Several experiments have been carried out to study and reduce this problem. In these experiments, textiles stained with different kinds of Particulate Soils were cleaned using a 25 L CO2 dry-cleaning set-up. It was found that the redeposition level increases along with washing time, while rinsing has little influence. Modifying the filtration system by using scavenger textile, or adding a cellulose compound to the cleaning vessel as anti redeposition agent can significantly reduce redeposition.
M J E Van Roosmalen - One of the best experts on this subject based on the ideXlab platform.
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Redeposition in CO2 textile dry cleaning
Journal of Supercritical Fluids, 2013Co-Authors: Stevia Sutanto, M J E Van Roosmalen, Geert-jan WitkampAbstract:Abstract Perchloroethylene (PER) is commonly used as cleaning solvent in the textile dry-cleaning industry but this chemical is toxic by nature. One of the potential PER replacements is carbon dioxide (CO2), which is non-toxic, cheap, and widely available. Previous studies have indicated that the Particulate Soil removal with CO2 is lower compared to that of PER. While the Particulate Soil removal of the CO2 dry-cleaning was studied, it was found that redeposition of Particulate Soil occurs. Several experiments have been carried out to study and reduce this problem. In these experiments, textiles stained with different kinds of Particulate Soils were cleaned using a 25 L CO2 dry-cleaning set-up. It was found that the redeposition level increases along with washing time, while rinsing has little influence. Modifying the filtration system by using scavenger textile, or adding a cellulose compound to the cleaning vessel as anti redeposition agent can significantly reduce redeposition.
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Amino acid based surfactants for dry-cleaning with high-pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:Abstract The currently most used dry-cleaning solvent is perchloroethylene (PER). Carbon dioxide could be an ideal solvent to replace PER. Amino acid based surfactants have been studied for dry-cleaning with carbon dioxide. For the production of amino acid based surfactants, renewable, low-cost raw materials are used. Furthermore, these surfactants have a low toxicity, are biodegradable and not skin irritating. These characteristics make the amino acid based surfactants attractive for dry-cleaning with carbon dioxide. The amino acid based surfactants give good results for dry-cleaning with liquid CO2. The surfactant Amihope LL (N-lauroyl- l -lysine) gives the best cleaning-results. An important process parameter using this surfactant is the addition of water. The addition of water is required for sufficient removal of non-Particulate Soils. However, when no water is added to the system, there is a large increase in Particulate Soil removal. Therefore, a two-bath process is proposed. The first bath is for Particulate Soil removal and has optimal conditions for Particulate Soil removal; the second bath has optimal conditions for non-Particulate Soil removal. The two-bath process using Amihope LL gives excellent results: the result for Particulate Soil removal is 84% compared to the results for PER, the result for non-Particulate Soil removal is 98% compared to PER and the overall result is 92% compared to PER.
-
surfactants for Particulate Soil removal in dry cleaning with high pressure carbon dioxide
Journal of Supercritical Fluids, 2004Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, Geert-jan WitkampAbstract:The removal of Particulate Soils from textile in dry-cleaning with CO2 is insufficient compared to perchloroethylene (PER). Especially the removal of relatively small particles (<20 μm) poses a problem. Various anionic and amine based surfactants have been investigated to enhance the removal of Particulate, but also of non-Particulate Soils in dry-cleaning with high-pressure CO2. The cleaning performance index for relatively small Particulate Soil (CPIpart) increased from 24% (when no surfactants were used) to a maximum of 51% (when surfactants were used), which shows that particle removal is possible in CO2 dry-cleaning. The use of these surfactants, however, does not bring particle removal up to the level of PER (CPIpart of 68%). The removal of non-Particulate Soils in CO2 with water, surfactant and co-solvent is better than in PER. The overall results using the investigated surfactants are promising; the overall result increases from 70% (when no surfactants are used) to 87% (when surfactants are used) compared to the level when using PER. Surfactant particles were formed in all experiments. In the case of the amines, these particles may be formed by reaction. The formed charged surfactant particles are probably responsible for the removal of the Soil particles from the textile. The charged surfactant particles may adhere to the Soil particles and/or fabric, thereby establishing an element of repulsion and/or a steric barrier. The use of a co-solvent (iso-propanol) had a positive effect on the removal of Particulate and non-Particulate Soils when using amines. However, when anionic surfactants were used, the addition of a co-solvent had a pronounced negative effect on Particulate Soil removal.
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Dry-cleaning with high-pressure carbon dioxide—the influence of mechanical action on washing-results
Journal of Supercritical Fluids, 2003Co-Authors: M J E Van Roosmalen, GREERT FEYE WOERLEE, M. Van Diggelen, Geert-jan WitkampAbstract:Abstract Previous studies indicate that the removal of non-polar Soils in CO2 is comparable to the level of dry-cleaning in perchloroethylene (PER). However, these studies show that the removal of Particulate Soil is insufficient in CO2 compared to PER. Particle removal can be increased by the use of more mechanical action and/or the use of surfactants. From experiments, it is concluded that the removal of relatively large particles like sand increases with increasing mechanical action. However, the level of mechanical action has no influence on the removal of relatively small Particulate and non-Particulate Soils (with the exception of clay on wool). Increasing the amount of mechanical action is therefore not the solution that will lead to the increase of the washing-results for relatively small particles (like carbon black and clay) up to the level of the washing-results using PER. The removal of relatively small Particulate Soils in CO2 can be improved by the use of suitable surfactants that reduce adhesion forces. A model for quantifying the amount of mechanical action has been developed. This model can be used to predict the optimal process conditions for relatively large particle removal. It is concluded (from the model and experiments) that the level of highest mechanical action in CO2 is obtained in a two-phase environment at low pressure and temperature and that 75 RPM is the optimal number of revolutions in our system. At these conditions, however, the washing-results for small particles are not as good as the washing-results for these particles in PER.