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Mark J. Suto - One of the best experts on this subject based on the ideXlab platform.
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SolutIon-phase parallel synthesis using Ion-Exchange Resins
Tetrahedron, 1998Co-Authors: Mark J. Suto, Leah M. Gayo-fung, Moorthy S. S. Palanki, Sullivan RobertAbstract:Abstract Ion-Exchange Resins are useful as scavengers in solutIon-phase parallel synthesis. Ester and amide libraries have been generated using basic Ion-Exchange Resins to facilitate the formatIon of products and to remove reactIon byproducts. Acidic Ion-Exchange Resins have been used as selective amine scavengers in the synthesis of urea and amine libraries. Several compound libraries have been prepared using the basic Ion-Exchange resin Amberlyst 21 as part of our lead optimizatIon program. The utility of Ion-Exchange Resins as a means of generating both large and small focused libraries will be reviewed. Acidic and basic Ion-Exchange Resins are useful reagents in solutIon-phase parallel synthesis. Ester and amide libraries have been generated using basic Ion-Exchange Resins, and acidic Ion-Exchange Resins have been used as selective amine scavengers in the synthesis of urea and amine libraries. The utility of Ion-Exchange Resins as a means of generating focused libraries will be discussed.
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Ion-Exchange Resins for solutIon phase parallel synthesis of chemical libraries
Tetrahedron Letters, 1997Co-Authors: Leah M. Gayo, Mark J. SutoAbstract:Abstract Described are various techniques that employ Ion-Exchange Resins for the solutIon-phase synthesis of chemical libraries. We have found these Resins to be useful as reagents and/or scavengers in a variety of reactIons. Nine basic Ion-Exchange Resins were evaluated for the catalysis and purificatIon of an amide synthesized from an acid chloride. A number of the Resins examined provided products in >95% purity. Acidic Ion-Exchange Resins were also useful as scavengers in the synthesis of ureas. A demonstratIon of the utility of these Resins for the preparatIon of amide, ester and urea libraries is also described.
R.d. Sanders - One of the best experts on this subject based on the ideXlab platform.
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RadiatIon degradatIon in organic Ion Exchange Resins
Waste Management, 2003Co-Authors: J.w. Mcconnell, D.a. Johnson, R.d. SandersAbstract:Abstract The EPICOR-II Resin/Liner InvestigatIon: Low-Level Waste Data Base Development Program, funded by the U.S. Nuclear Regulatory CommissIon, studied the degradatIon effects in EPICOR-II organic Ion Exchange Resins caused by internal radiatIon. Results of the third sampling analysis of Ion Exchange Resins from prefilters PF-8 and PF-20 are compared with baseline data from tests performed on unirradiated Resins and with results from the first and second samplings to determine if degradatIon has occurred because of the high internal radiatIon dose. Those results are also compared to findings of other researchers.
Cosme Fernanda - One of the best experts on this subject based on the ideXlab platform.
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Tartrate stabilisatIon of Rosé wine using Ion Exchange Resins
2018Co-Authors: Borges Rita, Fernandes Conceição, Marques Celeste, Matos Carlos, Vilela Alice, Nunes, Fernando M., Cosme FernandaAbstract:Tartaric stabilisatIon is essential to satisfy the quality criteria of wines. To prevent wine tartaric precipitates, potassium hydrogen tartrate (KHT) and calcium tartrate (CaT), several techniques can be used. The additIon of oenological products, such as metatartaric acid and carboxymetilcelulose (CMC’s) as well as the use of Ion Exchange Resins are acceptable techniques for tartaric stabilizatIon by the OIV, according to ResolutIon 43/2000. The aim of this study was to evaluate the Ion Exchange Resins effect on wine tartaric stabilizatIon efficiency and wine quality, compared to effect of the additIon of different oenological additives. A Rosé wine from 2015 vintage, Douro regIon, was used for the experiments. Ion Exchange resin versus CMC’s, with different structural features (Guise et al. 2014), and metatartaric acid were tested concerning wine tartaric stabilizatIon, physicochemical and sensory characteristics. As expected, all treatments stabilized the Rosé wine. After treatment with Ion Exchange Resins, Rosé wine pH was lower and consequently wine acidity increased. Also, mineral compositIon (magnesium, calcium, potassium and sodium) decreased after treatment with Ion Exchange Resins. In general, in wines treated with Ion Exchange Resins, there are a decrease in polymeric pigments and colour intensity. Sensory analyses of this wine also showed, for the visual descriptor, colour intensity and limpidity attributes, that they were lesser and higher scored, respectively. Results from this preliminary study suggest that Ion Exchange Resins could be an effective alternative for wine tartaric stabilizatIon.This work was partially funded by the Chemical Research Center (CQ-UTAD). AdditIonal thanks to AEBBioquímica Portuguesa and to Gran Cruz.info:eu-repo/semantics/publishedVersio
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Tartrate stabilisatIon of Rosé wine using Ion Exchange Resins
2018Co-Authors: Borges Rita, Fernandes Conceição, Marques Celeste, Matos Carlos, Vilela Alice, Nunes, Fernando M., Cosme FernandaAbstract:Tartaric stabilisatIon is essential to satisfy the quality criteria of wines. To prevent wine tartaric precipitates, potassium hydrogen tartrate (KHT) and calcium tartrate (CaT), several techniques can be used. The additIon of oenological products, such as metatartaric acid and carboxymetilcelulose (CMC’s) as well as the use of Ion Exchange Resins are acceptable techniques for tartaric stabilizatIon by the OIV, according to ResolutIon 43/2000. The aim of this study was to evaluate the Ion Exchange Resins effect on wine tartaric stabilizatIon efficiency and wine quality, compared to effect of the additIon of different oenological additives. A Rosé wine from 2015 vintage, Douro regIon, was used for the experiments. Ion Exchange resin versus CMC’s, with different structural features (Guise et al. 2014), and metatartaric acid were tested concerning wine tartaric stabilizatIon, physicochemical and sensory characteristics. As expected, all treatments stabilized the Rosé wine. After treatment with Ion Exchange Resins, Rosé wine pH was lower and consequently wine acidity increased. Also, mineral compositIon (magnesium, calcium, potassium and sodium) decreased after treatment with Ion Exchange Resins. In general, in wines treated with Ion Exchange Resins, there are a decrease in polymeric pigments and colour intensity. Sensory analyses of this wine also showed, for the visual descriptor, colour intensity and limpidity attributes, that they were lesser and higher scored, respectively. Results from this preliminary study suggest that Ion Exchange Resins could be an effective alternative for wine tartaric stabilizatIon.We appreciate the financial support provided to the CQ-VR Research unit in Vila Real (PEst-OE/QUI/UI0616/2014). AdditIonal thanks to AEB Bioquímica Portuguesainfo:eu-repo/semantics/publishedVersio
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Tartrate stabilizatIon of rosé wine using Ion Exchange Resins: Impact on wine sensory characteristics
2018Co-Authors: Borges Rita, Fernandes Conceição, Marques Celeste, Matos Carlos, Vilela Alice, Nunes, Fernando M., Filipe-ribeiro L., Cosme FernandaAbstract:Tartaric precipitatIon in bottled wine is an important problem for the wine industry by the sensory undesirable aspect and, therefore, wineries employed several treatments to prevent this precipitatIon to satisfy the quality criteria of wine consumers. For example, according to ResolutIon 43/2000 [1], the additIon of certain stabilizers, such as metatartaric acid and carboxymethylcellulose (CMC) or the treatment of the wine with Ion Exchange Resins, are accepted and have been successfully used to prevent tartaric precipitatIon in white and red wine [2,3]. However, there are few studies regarding rosé wine. The main difference concerning these two stabilizatIon processes is that the Ion Exchange Resins removes the compounds that contribute to tartrate instability. AnIon Exchangers are not allowed by the OIV [1] due to the negative effects on the wine physiochemical and sensory quality [4,5]. Therefore, the aim of this study was to evaluate the effect of catIon Exchange Resins on rosé wine tartaric stabilizatIon efficiency and wine sensory quality compared to the effect of the additIon of different enological stabilizers. In this study a rosé wine from the Douro Valley demarcated regIon, 2015 vintage, was used, and Ion Exchange resin versus tested concerning their tartaric stabilizatIon efficiency and sensory quality. In this work almost 30% from the total rosé wine volume was treated by Ion Exchange Resins. As expected, all treatments assayed stabilized the rosé wine. The catIon Exchange Resins process could be a useful tool to maintain wine quality, as the sensory analysis data showed. Main differences were obtained for the wine visual descriptor, namely limpidity attributes, which was higher scored in the wine treated with Ion Exchange Resins. These results show that Ion Exchange Resins could be an interesting process for rosé wine tartaric stabilizatIon.This work was funded by the Chemical Research Centre (CQ-UTAD). AdditIonal thanks to AEB Bioquímica Portuguesainfo:eu-repo/semantics/publishedVersio
S Rengaraj - One of the best experts on this subject based on the ideXlab platform.
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batch adsorptive removal of copper Ions in aqueous solutIons by Ion Exchange Resins 1200h and irn97h
Korean Journal of Chemical Engineering, 2004Co-Authors: S Rengaraj, Cheol Kyun Joo, Younghun Kim, Kyunghee ChoiAbstract:The removal of copper from aqueous solutIon by Ion Exchange Resins, such as 1200H and IRN97H, is described. Effect of initial metal Ion concentratIon, agitatIon time and pH on adsorptIon capacities of Ion Exchange Resins was investigated in a batch mode. The adsorptIon process, which is pH dependent, shows maximum removal of copper in the pH range 2-7 for an initial copper concentratIon of 10 mg/L. The experimental data have been analyzed by using the Freundlich, Langmuir, Redlich-Peterson, Temkin and Dubinin-Radushkevich isotherm models. The batch sorptIon kinetics have been tested for a first-order, pseudo-first order and pseudo-second order kinetic reactIon models. The rate constants of adsorptIon for all these kinetic models have been calculated. Results showed that the intraparticle diffusIon and initial sorptIon into Resins of Cu(II) in the Ion Exchange Resins was the main rate limiting step. The uptake of copper by the Ion Exchange Resins was reversible and thus has good potential for the removal/recovery of copper from aqueous solutIons. We conclude that such Ion Exchange Resins can be used for the efficient removal of copper from water and wastewater.
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kinetics of removal of chromium from water and electronic process wastewater by Ion Exchange Resins 1200h 1500h and irn97h
Journal of Hazardous Materials, 2003Co-Authors: S Rengaraj, Cheol Kyun Joo, Younghun KimAbstract:The removal of chromium from aqueous solutIon by an Ion Exchange resin is described. Ion Exchange Resins 1200H, 1500H and IRN97H show a remarkable increase in sorptIon capacity for chromium, compared to other adsorbents. The adsorptIon process, which is pH dependent show maximum removal of chromium in the pH range 2-6 for an initial chromium concentratIon of 10mg/l. The metal Ion adsorptIon obeyed linear, Langmuir and Freundlich isotherms. The adsorptIon of chromium on these catIon Exchange Resins follows first-order reversible kinetics and pseudo-first-order kinetics. The intraparticle diffusIon of chromium on Ion Exchange Resins represents the rate-limiting step. The uptake of chromium by the Ion Exchange Resins was reversible and thus have good potential for the removal/recovery of chromium from aqueous solutIons. We conclude that such Ion Exchange Resins can be used for the efficient removal of chromium from water and wastewater.
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kinetics of adsorptIon of co ii removal from water and wastewater by Ion Exchange Resins
Water Research, 2002Co-Authors: S Rengaraj, Seunghyeo MooAbstract:The capacity of Ion Exchange Resins, IRN77 and SKN1, for removal of cobalt from aqueous solutIon has been investigated under different conditIons namely initial solutIon pH, initial metal-Ion concentratIon, and contact time. The equilibrium data obtained in this study have been found to fit both the Langmuir and Freundlich adsorptIon isotherms. The adsorptIon of Co(II) on these Resins follows first-order reversible kinetics. The film diffusIon of Co(II) in these Ion Exchange Resins was shown to be the main rate limiting step. The studies showed that these catIon Exchange Resins can be used as efficient adsorbent material for the removal of Co(II) from aqueous solutIons.
J.w. Mcconnell - One of the best experts on this subject based on the ideXlab platform.
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RadiatIon degradatIon in organic Ion Exchange Resins
Waste Management, 2003Co-Authors: J.w. Mcconnell, D.a. Johnson, R.d. SandersAbstract:Abstract The EPICOR-II Resin/Liner InvestigatIon: Low-Level Waste Data Base Development Program, funded by the U.S. Nuclear Regulatory CommissIon, studied the degradatIon effects in EPICOR-II organic Ion Exchange Resins caused by internal radiatIon. Results of the third sampling analysis of Ion Exchange Resins from prefilters PF-8 and PF-20 are compared with baseline data from tests performed on unirradiated Resins and with results from the first and second samplings to determine if degradatIon has occurred because of the high internal radiatIon dose. Those results are also compared to findings of other researchers.
