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公开(公告)号：US4287132A
公开(公告)日：1981-09-01
申请号：US191543
申请日：1980-09-29
IPC分类号： C07C263/04 , C07C265/12 , C07C271/06 , C07C118/00 , C07C125/07
CPC分类号： C07C263/04
摘要： In the process of producing a diisocyanate comprising(a) condensing and rearranging alkyl phenylcarbamate and formaldehyde under acidic conditions to form dialkyl methylene bis(phenylcarbamate) and(b) thermally decomposing the dialkyl methylene bis(phenylcarbamate) to diphenylmethane diisocyanate,the improvement comprises prior to step (b) treating the reaction product of (a) by first distilling the reaction product of (a) under reduced pressure at a temperature below 120.degree. C. until all solvent is removed and 65-85% of the unreacted alkyl phenylcarbamate present is removed, discontinuing the distillation, adding a polar solvent to undistilled distillation residue and selectively crystallizing and separating dialkyl methylene bis(phenylcarbamate) from the distillation residue.
摘要翻译： 在制备二异氰酸酯的方法中，（a）在酸性条件下使苯基氨基甲酸烷基酯和甲醛缩合并重排，形成二烷基亚甲基双（苯基氨基甲酸酯）和（b）将二烷基亚甲基双（苯基氨基甲酸酯）热分解成二苯基甲烷二异氰酸酯， （b）处理（a）的反应产物，首先在低于120℃的温度下在减压下蒸馏（a）的反应产物，直至除去所有溶剂，并将65-85％的未反应的烷基苯基氨基甲酸铵存在 ，停止蒸馏，向未蒸馏残余物中加入极性溶剂，并选择性地从蒸馏残余物中结晶并分离二烷基亚甲基双（苯基氨基甲酸酯）。
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公开(公告)号：US4433173A
公开(公告)日：1984-02-21
申请号：US384317
申请日：1982-06-02
IPC分类号： C07C45/83
CPC分类号： C07C45/83
摘要： Purification of acetophenone containing difficultly separable impurities by extractive distillation with a solvent selected from the group consisting of oligomers of 1,2-glycols, said oligomers having from 4 to 9 carbon atoms per molecule.
摘要翻译： 通过萃取蒸馏纯化含有难分离杂质的苯乙酮，其中溶剂选自1,2-二醇的低聚物，所述低聚物每分子具有4至9个碳原子。
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公开(公告)号：US4578357A
公开(公告)日：1986-03-25
申请号：US507856
申请日：1983-06-27
申请人： Frank W. Melpolder
发明人： Frank W. Melpolder
CPC分类号： G01F23/04 , G01N31/22 , G01N31/221
摘要： A visual indicating paste composition for producing a detectable color change upon contact with an aqueous solution comprising an indicator dye capable of changing color in the pH range between about 7 and about 11, an inorganic base in the form of a caustic powder dispersed in a liquid carrier capable of absorbing water which is not rapidly leached by water or hydrocarbon, and a minor amount of a boron-containing compound, is provided. When applied to a measuring probe, the paste composition is particularly adapted for detecting the water level in the bottom of tanks and delivery systems containing gasoline, and especially gasoline containing oxygenated blending components, by producing a clear detectable color change without bleeding or run-off upon contact with an aqueous solution. The paste composition exhibits long shelf life and improved water tolerance.
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公开(公告)号：US4717671A
公开(公告)日：1988-01-05
申请号：US816038
申请日：1986-01-03
申请人： Frank W. Melpolder
发明人： Frank W. Melpolder
CPC分类号： G01F23/04 , G01N31/22 , G01N31/221
摘要： A visual indicating paste composition for producing a detectable color change upon contact with an aqueous solution comprising an indicator dye capable of changing color in the pH range between about 7 and about 11, an inorganic base in the form of a caustic powder dispersed in a liquid carrier capable of absorbing water which is not rapidly leached by water or hydrocarbon, and a minor amount of a boron-containing compound, is provided. When applied to a measuring probe, the paste composition is particularly adapted for detecting the water level in the bottom of tanks and delivery systems containing gasoline, and especially gasoline containing oxygenated blending components, by producing a clear detectable color change without bleeding or run-off upon contact with an aqueous solution. The paste composition exhibits long shelf life and improved water tolerance.
摘要翻译： 一种用于在与包含能够在约7至约11之间的pH范围内变色的指示剂染料的水溶液接触时产生可检测颜色变化的视觉指示糊组合物，分散在液体中的苛性粉末形式的无机碱 能够吸收不被水或烃快速浸出的水的载体和少量的含硼化合物。 当应用于测量探针时，该糊剂组合物特别适用于通过产生清晰可检测的颜色变化而没有出血或流出来检测含有汽油的罐和输送系统的底部的水位，特别是含有含氧混合组分的汽油 与水溶液接触。 糊剂组合物具有长的保质期和改善的耐水性。
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公开(公告)号：US4699885A
公开(公告)日：1987-10-13
申请号：US490744
申请日：1983-05-02
CPC分类号： G01F23/04 , G01N31/22 , G01N31/221
摘要： A visual indicating paste composition for producing a detectable color change upon contact with an aqueous solution comprising an indicator dye capable of changing color in the pH range between about 7 and about 11, said base being dispersed in a liquid carrier capable of absorbing water but which is not rapidly leached by water or hydrocarbon, is provided. When applied to a measuring probe, the paste composition is particularly adapted for detecting the water level in the bottom of tanks and delivery systems containing gasoline, and especially gasoline containing oxygenated blending components, by producing a clear detectable color change without bleeding or run-off upon contact with an aqueous solution.
摘要翻译： 一种视觉指示糊组合物，用于在与包含能够在约7至约11之间的pH范围内变色的指示剂染料的水溶液接触时产生可检测的颜色变化，所述碱分散在能够吸收水的液体载体中， 不被水或烃快速浸出。 当应用于测量探针时，该糊剂组合物特别适用于通过产生清晰可检测的颜色变化而没有出血或流出来检测含有汽油的罐和输送系统的底部的水位，特别是含有含氧混合组分的汽油 与水溶液接触。
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公开(公告)号：US4198530A
公开(公告)日：1980-04-15
申请号：US912622
申请日：1978-06-29
CPC分类号： B01D3/009 , C07C41/06 , Y02P20/127
摘要： A mixed C.sub.4 hydrocarbon stream containing from 5 to 60% isobutene is mixed with methanol providing from about 2% to about 20% excess methanol (stoichiometry based on isobutene content) to provide fresh feed for preparing tertiary butyl methyl ether in a reaction zone containing acidic ion exchange catalyst. Formation of trouble-some amounts of diisobutylene is repressed by the presence of the excess methanol. The effluent comprising TBME, excess methanol, and unreacted C.sub.4 hydrocarbons is directed to a unique purification zone. The butenes are distilled from the effluent at a pressure from about 7 to 25 atmospheres, preferably at about 12 to 20 atmospheres. Surprisingly all of the excess methanol is azeotropically removed with the C.sub.4 hydrocarbons by the pressurized azeotropic distillation, leaving a bottoms consisting of a technical grade of TBME free from troublesome amounts of methanol.
摘要翻译： 将含有5至60％异丁烯的混合C4烃流与甲醇混合，提供约2％至约20％的过量甲醇（基于异丁烯含量的化学计量），以在含有酸的反应区中提供用于制备叔丁基甲基醚的新鲜进料 离子交换催化剂。 形成麻烦 - 一些量的二异丁烯被过量的甲醇的存在所抑制。 包含TBME，过量甲醇和未反应的C 4烃的流出物被引导到独特的纯化区。 在约7至25个大气压，优选约12至20个大气压的压力下，从流出物中蒸馏丁烯。 令人惊奇的是，通过加压共沸蒸馏与C4烃共沸除去所有过量的甲醇，留下由不含麻烦量甲醇的工业级TBME组成的塔底物。
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