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Johannes H. Knoetze - One of the best experts on this subject based on the ideXlab platform.
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concentration of wax like alcohol Ethoxylates with supercritical propane
Chemical Engineering & Technology, 2007Co-Authors: C E Schwarz, Izak Nieuwoudt, Johannes H. KnoetzeAbstract:The virtual insolubility of synthetic wax can be improved by ethoxylating the wax with a polyethylene glycol segment to form an alcohol ethoxylate. Current methods lead to a wide ethylene oxide distribution. This work shows that supercritical propane can fractionate alcohol Ethoxylates according to the ethylene oxide content. Solubility measurements in propane at 408 K show total solubility of an alcohol mixture (average 40 carbon atoms) below 140 bar and a region of immiscibility between 0.975 and 0.5 at pressures below 275 bar for the alcohol ethoxylate mixture (average 40 carbon atoms, 50% ethoxylation). This large solubility difference shows that fractionation of the alcohol ethoxylate with propane is possible. Countercurrent pilot plant runs proved that separation is possible and with energy integration and selection of the correct decompression process the technology is both technically and economically viable.
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solubility measurements of high molecular mass n alkanes n alcohols and alcohol Ethoxylates in supercritical propane
Fluid Phase Equilibria, 2006Co-Authors: C E Schwarz, Izak Nieuwoudt, Johannes H. KnoetzeAbstract:Abstract Pseudo binary high-pressure solubility measurements of a commercial mixture of high molecular mass n-alcohols (Mave = 566 g/mol) in propane and a commercial mixture of high molecular mass alcohol Ethoxylates (50% ethoxylated, Mave = 1100 g/mol) in propane were conducted at temperatures between 375 and 410 K and pressures up to 275 bar. The propane–n-alcohol solubility curve shows complete solubility at pressures below 150 bar. At these conditions the propane–alcohol ethoxylate solubility curve shows a region of liquid-fluid immiscibility as well as a solubility inversion with temperature. Comparing the solubility of an n-alkane, an n-alcohol and a 50% ethoxylated alcohol ethoxylate, all with the same average hydrocarbon backbone length, in propane it is seen that the n-alkane is the most soluble, followed by the n-alcohol and the alcohol ethoxylate is the least soluble.
C E Schwarz - One of the best experts on this subject based on the ideXlab platform.
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concentration of wax like alcohol Ethoxylates with supercritical propane
Chemical Engineering & Technology, 2007Co-Authors: C E Schwarz, Izak Nieuwoudt, Johannes H. KnoetzeAbstract:The virtual insolubility of synthetic wax can be improved by ethoxylating the wax with a polyethylene glycol segment to form an alcohol ethoxylate. Current methods lead to a wide ethylene oxide distribution. This work shows that supercritical propane can fractionate alcohol Ethoxylates according to the ethylene oxide content. Solubility measurements in propane at 408 K show total solubility of an alcohol mixture (average 40 carbon atoms) below 140 bar and a region of immiscibility between 0.975 and 0.5 at pressures below 275 bar for the alcohol ethoxylate mixture (average 40 carbon atoms, 50% ethoxylation). This large solubility difference shows that fractionation of the alcohol ethoxylate with propane is possible. Countercurrent pilot plant runs proved that separation is possible and with energy integration and selection of the correct decompression process the technology is both technically and economically viable.
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solubility measurements of high molecular mass n alkanes n alcohols and alcohol Ethoxylates in supercritical propane
Fluid Phase Equilibria, 2006Co-Authors: C E Schwarz, Izak Nieuwoudt, Johannes H. KnoetzeAbstract:Abstract Pseudo binary high-pressure solubility measurements of a commercial mixture of high molecular mass n-alcohols (Mave = 566 g/mol) in propane and a commercial mixture of high molecular mass alcohol Ethoxylates (50% ethoxylated, Mave = 1100 g/mol) in propane were conducted at temperatures between 375 and 410 K and pressures up to 275 bar. The propane–n-alcohol solubility curve shows complete solubility at pressures below 150 bar. At these conditions the propane–alcohol ethoxylate solubility curve shows a region of liquid-fluid immiscibility as well as a solubility inversion with temperature. Comparing the solubility of an n-alkane, an n-alcohol and a 50% ethoxylated alcohol ethoxylate, all with the same average hydrocarbon backbone length, in propane it is seen that the n-alkane is the most soluble, followed by the n-alcohol and the alcohol ethoxylate is the least soluble.
Izak Nieuwoudt - One of the best experts on this subject based on the ideXlab platform.
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concentration of wax like alcohol Ethoxylates with supercritical propane
Chemical Engineering & Technology, 2007Co-Authors: C E Schwarz, Izak Nieuwoudt, Johannes H. KnoetzeAbstract:The virtual insolubility of synthetic wax can be improved by ethoxylating the wax with a polyethylene glycol segment to form an alcohol ethoxylate. Current methods lead to a wide ethylene oxide distribution. This work shows that supercritical propane can fractionate alcohol Ethoxylates according to the ethylene oxide content. Solubility measurements in propane at 408 K show total solubility of an alcohol mixture (average 40 carbon atoms) below 140 bar and a region of immiscibility between 0.975 and 0.5 at pressures below 275 bar for the alcohol ethoxylate mixture (average 40 carbon atoms, 50% ethoxylation). This large solubility difference shows that fractionation of the alcohol ethoxylate with propane is possible. Countercurrent pilot plant runs proved that separation is possible and with energy integration and selection of the correct decompression process the technology is both technically and economically viable.
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solubility measurements of high molecular mass n alkanes n alcohols and alcohol Ethoxylates in supercritical propane
Fluid Phase Equilibria, 2006Co-Authors: C E Schwarz, Izak Nieuwoudt, Johannes H. KnoetzeAbstract:Abstract Pseudo binary high-pressure solubility measurements of a commercial mixture of high molecular mass n-alcohols (Mave = 566 g/mol) in propane and a commercial mixture of high molecular mass alcohol Ethoxylates (50% ethoxylated, Mave = 1100 g/mol) in propane were conducted at temperatures between 375 and 410 K and pressures up to 275 bar. The propane–n-alcohol solubility curve shows complete solubility at pressures below 150 bar. At these conditions the propane–alcohol ethoxylate solubility curve shows a region of liquid-fluid immiscibility as well as a solubility inversion with temperature. Comparing the solubility of an n-alkane, an n-alcohol and a 50% ethoxylated alcohol ethoxylate, all with the same average hydrocarbon backbone length, in propane it is seen that the n-alkane is the most soluble, followed by the n-alcohol and the alcohol ethoxylate is the least soluble.
Christian Gauvrit - One of the best experts on this subject based on the ideXlab platform.
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Ethoxylated rapeseed oil derivatives as non-ionic adjuvants for glyphosate
Pest Management Science, 2007Co-Authors: Christian Gauvrit, Alain Milius, Thomas Müller, Gérard TrouveAbstract:In a study aimed at finding environmentally benign adjuvants for glyphosate, Ethoxylates of rapeseed oil and of methylated rapeseed oil were synthesized, with ethylene oxide (EO) content up to 40 and 8 respectively. They had less influence on spray retention by barley shoots than ethoxylated (15 EO) tallow amine (ETA). At 10 g L-1, ethoxylated rapeseed oil with 30 or 40 EO and ethoxylated methylated rapeseed oil with 6 or 8 EO promoted glyphosate uptake by barley leaves to a greater extent than ETA at the same concentration. However, uptake rates were similar when the concentration was lowered to 2.8 and 3.1 g L-1 for rapeseed oil derivatives and ETA respectively. In the case of ethoxylated methylated rapeseed oil with 8 EO (MeOil-8), glyphosate uptake increased when MeOil-8 concentration was raised from 5 to 10 g L-1. In bioassays under controlled conditions, ethoxylated rapeseed oil with 40 EO (Oil-40) and MeOil-8 were slightly less effective than ETA in favouring the efficacy of glyphosate on barley. The same was found on ryegrass. However, both rapeseed oil derivatives compared well with glyphosate formulants such as ethoxylated diethylamine and alkyl ethoxy phosphate. In one field experiment, the efficacy of glyphosate in the presence of Oil-40, MeOil-8 or ETA was comparable with that of a commercial formulation. In another trial, MeOil-8 was as effective as ETA, but Oil-40 performed less well. It is concluded that Ethoxylates of rapeseed oil and of methylated rapeseed oil are a promising chemistry for glyphosate adjuvants, provided that their ethylene oxide content is high. Copyright © 2007 Society of Chemical Industry
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Ethoxylated rapeseed oil derivatives as novel adjuvants for herbicides.
Pest Management Science, 2002Co-Authors: Thomas Müller, Bernard Brancq, Alain Milius, Nathalie Okori, Claude Vaille, Christian GauvritAbstract:Ethoxylates of rapeseed oil and of methylated rapeseed oil were synthesized and tested as adjuvants for 2,4-D and phenmedipham. Provided they had less than 6 units of ethylene oxide (EO), 1.0 to 10 g litre−1 Ethoxylates in water induced droplet spreading on barley leaves. In an acetone-based medium all derivatives strongly promoted the foliar uptake of 2,4-D, with no clear influence of the ethoxylation degree. In the same medium there was a negative influence of ethoxylate chain length on the foliar uptake of phenmedipham. In a water-based medium, phenmedipham applied with rapeseed oil emulsified with ethoxylated (20 EO) rapeseed oil displayed uptake rates close to a commercial preparation. The same was true for phenmedipham applied with ethoxylated (2 EO) methylated rapeseed oil. In bioassays, phenmedipham prepared with methylated rapeseed oil emulsified with ethoxylated (20 EO) rapeseed oil was as efficacious on barley as a commercial formulation. The same was true for phenmedipham prepared with ethoxylated (2 EO) methylated rapeseed oil. However, neither rapeseed oil nor methylated rapeseed oil emulsified with ethoxylated (2 EO) methylated rapeseed oil conferred good efficacy to phenmedipham. Hence, ethoxylated rapeseed oil derivatives are promising adjuvants or formulants for herbicides. © 2002 Society of Chemical Industry
Pablo A Laramartin - One of the best experts on this subject based on the ideXlab platform.
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environmental analysis of alcohol Ethoxylates and nonylphenol ethoxylate metabolites by ultra performance liquid chromatography tandem mass spectrometry
Analytical and Bioanalytical Chemistry, 2012Co-Authors: Eduardo Gonzalezmazo, Pablo A Laramartin, Bruce J BrownawellAbstract:Surfactants and their metabolites can be found in aquatic environments at relatively high concentrations compared with other micropollutants due in part to the exceptionally large volumes produced every year. We have focused our attention here on the most widely used nonionic surfactants, alcohol Ethoxylates (AEOs), and on nonylphenol ethoxylate (NPEO) degradation products (short-chain nonylphenol Ethoxylates, NP1-3EO, nonylphenol, NP, and nonylphenol ethoxycarboxylates, NP1-2EC), which are endocrine-disrupting compounds. Our main objective in this work was to develop a methodology aimed at the extraction, isolation, and improved analysis of these analytes in environmental samples at trace levels. Extraction recoveries of target compounds were determined for sediment samples after ultrasonic extraction and purification using HLB or C18 solid-phase extraction minicolumns. Recovery percentages were usually between 61 and 102% but were lower for longer AEO ethoxymers. Identification and quantification of target compounds was carried out using a novel ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC–MS-MS) approach, a combination that provides higher sensitivity and faster analysis than prior methods using conventional high-performance liquid chromatography–mass spectrometry. Limits of detection were usually below 0.5 ng/g, being higher for monoethoxylate species (>5 ng/g) because of poor ionization. The method was used for analyzing surface sediment samples collected at Jamaica Bay (NY) in 2008. The highest values (28,500 ng/g for NP, 4,200 ng/g for NP1-3EO, 22,400 ng/g for NP1-2EC, and 1,500 ng/g for AEOs) were found in a sampling station from a restricted water circulation area that is heavily impacted by wastewater discharges.