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一步法常温合成甲基橙刘建国*孙笃周(湘中地质实验研究所,娄底417000)甲基橙的合成已有较长历史。目前试剂生产厂家一般还是沿用经典的合成方法,即以对氨基苯磺酸为原料,用“逆加法”低温重氮化,其重氮盐在弱酸性介质中再与N,N-二甲基苯胺偶联反应而制得... 相似文献
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项晓燕 《中国石油和化工标准与质量》2011,31(7):35
以α-氯乙酰乙酸乙酯、甲酰胺、工业硫酸为原料制得4-甲基-5咪唑甲酸乙酯,再在金属钠-液氨体系还原成4-甲基-5-羟甲基咪唑。此方法缺点是:工艺路线长,操作繁杂,成本高。本文介绍采用以4-甲基咪唑为起始原料与多聚甲醛于酸性溶液中羟甲基化合成4-甲基-5-羟甲基咪唑盐酸盐工艺,具有设备简单,工艺流程及反应时间短,操作简便,收率高。 相似文献
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通过酸处理活性碳催化环氧苯乙烷制备苯乙醛,收率可达97.5%。并筛选了缩合反应催化剂,以三乙醇胺为催化剂实现了苯乙醛与海因的直接缩合。5-苯乙叉基海因收率50%。 相似文献
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研究了一步法合成4 - 亚硝基二苯胺的影响因素,得出最佳工艺条件:n( 氯化氢)∶n( 二苯胺) = 3∶1 ,反应温度20 ~30 ℃,反应时间4 h,pH 值6 ~7。产品收率大于98% ,产品质量分数在99% 以上。 相似文献
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PET一步法异收缩丝的成形研究 总被引:1,自引:0,他引:1
通过在FDY纺丝拉伸设备上作异收缩丝的成形试验,探索出利用喷丝头喷出的丝束单丝线密度不同,在特定的纺丝拉伸条件下,一步法纺出异收缩丝是可能的。 相似文献
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论述了国内NaSCN一步法腈纶生产的技术现状及质量改进的效果。进一步提出并分析了一步法工艺需继续改进的不足与方向,指出提高NaSCN一步法腈纶质量已成为提高竞争能力的关键。 相似文献
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一步法生产涤纶FDY工艺的探讨 总被引:1,自引:3,他引:1
利用KV731纺丝设备一步法生产出涤纶FDY,探讨了热辊拉伸和熔体温度对纤维质量的影响。采用高特性粘数的聚酯切片,严格控制纺丝工艺,可以在5000m/min的纺丝速度下纺制高质量的细旦涤纶FDY。 相似文献
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介绍了在涤纶FDY 复合丝生产线上生产一步法三异混纤丝的设备、工艺流程,并对生产工艺作了粗浅的探讨。 相似文献
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采用原位水热合成法在多孔α-Al2O3陶瓷管和工业Rasching环2种载体上一次合成制得结晶良好的Na-ZSM-5沸石分子筛膜,为制备新型催化精馏内构件奠定了基础。以四丙基溴化胺(tetrapropyl ammonium bromide,TPABr)为模板剂,硅溶胶为硅源,铝酸钠为铝源,氢氧化钠为碱源,按照20TPABr-5NaOH-Na2AlO2-30SiO2-900H2O的质量配比制成合成胶体溶液,晶化温度为180℃,晶化时间为120h。X射线衍射的结果表明:2种载体上所合成的分子筛膜均为典型的ZSM-5沸石膜。扫描电子显微镜的照片显示:载体表面完全被分子筛膜覆盖且表面晶体生长良好,晶粒尺寸在20~30μm之间,晶层厚度为20μm左右,载体表面的晶体普遍交连生长.晶体与载体结合牢固。详细比较和分析了2种载体上生长的沸石分子筛膜的晶形及晶貌。 相似文献
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The catalytic activity of a zeolite, HZSM-5, was evaluated for the synthesis of methyl tertiary-butyl ether (MTBE) in a fixed bed micro-reactor at temperatures from 75 to 115°C and pressures of 20 to 40?bar, Isobutene was used as the limiting reactant as it is in commercial operations. Isobutene conversions ranged from 10 to 89 percent and were completely selective to the formation of MTBE. Dimer formation was hindered by the unique pore size of the zeolite. Temperature and isobutene to catalyst ratio were the significant process variables. Pressure had no significant effect on conversion of the liquid phase reaction. The reaction rate was zero order with respect to methanol concentration and was correlated by a first order reversible reaction equation. This zeolite may have selectivity and stability advantages over the present commercial catalyst. 相似文献
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The catalytic activity of a zeolite, HZSM-5, was evaluated for the synthesis of methyl tertiary-butyl ether (MTBE) in a fixed bed micro-reactor at temperatures from 75 to 115°C and pressures of 20 to 40 bar, Isobutene was used as the limiting reactant as it is in commercial operations. Isobutene conversions ranged from 10 to 89 percent and were completely selective to the formation of MTBE. Dimer formation was hindered by the unique pore size of the zeolite. Temperature and isobutene to catalyst ratio were the significant process variables. Pressure had no significant effect on conversion of the liquid phase reaction. The reaction rate was zero order with respect to methanol concentration and was correlated by a first order reversible reaction equation. This zeolite may have selectivity and stability advantages over the present commercial catalyst. 相似文献