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在含有溴离子和大量的碳酸钙的葡萄糖溶液中,通以直流电,使溴离子在阳极(正极)被电化学氧化成溴单质,与水结合成溴水,进一步用于氧化葡萄糖制备葡萄糖酸,葡萄糖酸与碳酸钙反应生成葡萄糖酸钙,溴变为溴离子,形成了电化学辅助溴催化氧化葡萄糖制备葡萄糖酸钙的循环系统。所制备出的葡萄糖酸钙溶液与可溶性的硫酸钠,硫酸钾,硫酸锌和硫酸亚铁通过复分解反应制备出葡萄糖酸钠,葡萄糖酸钾,葡萄糖酸锌和葡萄糖酸铁,产率大于90%。 相似文献
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本工作研究了D-核糖的工业制备方法。葡萄糖在氢氧化钾溶液中氧化制取D-阿拉伯糖酸钙,通过D-核糖酸-γ-内酯再电解还原,是制取D-核糖较好的工业生产方法。经过试验研究和中间试制,获得了良好的收率和适宜的工业生产条件,D-核糖对葡萄糖收率为35.85%。 本文报导了本研究工作的第一部分D-阿拉伯糖酸钙的制备。作者对D-阿拉伯糖酸钙的制取方法,进行了研究和改进。对葡萄糖在不同温度和氢氧化钾浓度下的分解情况进行了考察。将葡萄糖溶于1.182—1.224N浓度氢氧化钾溶液中,于38—40℃及1—1.5公斤/厘米~2表压及强烈搅拌下用氧气氧化。并采取分步加碱和直接浓缩反应液分离D-阿拉伯糖酸钾的方法。分离钾盐时不采用溶媒,操作方便,设备简单。然后以氯化钙置换成D-阿拉伯糖酸钙。D-阿拉伯糖酸钙对葡萄糖的收率可达65.80%。 相似文献
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以D-葡萄糖和氧化锌为原料,在四氧化三铁固定化葡萄糖氧化酶催化下,用简便方法合成葡萄糖酸锌,并通过单因素试验确定各因素的合理范围。以反应温度、缓冲溶液pH、D-葡萄糖体积量为考察因素,以葡萄糖酸锌的产量为因变量,通过Box-Benhnken设计-响应面法优化葡萄糖酸锌制备工艺条件。根据建立的各因素与响应值之间的数学模型,确定最佳制备工艺条件为反应温度38℃、缓冲溶液pH 7.3、D-葡萄糖体积量3 mL,获得葡萄糖酸锌量的最高值为406.16 mg,与模型预测值偏差0.58%。结果表明,固定化酶法制备葡萄糖酸锌工艺简单、成本较低,具有较高的工业应用价值。 相似文献
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葡萄糖酸合成方法研究进展 总被引:2,自引:0,他引:2
介绍了葡萄糖氧化制备葡萄糖酸的各种氧化方法及进展,并讨论其原理及优缺点,主要讨论了工业上广泛使用的生物发酵法和近年来发展比较快的多相催化氧化法,重点介绍了催化氧化法制葡萄糖酸的催化剂失活和制备的研究情况. 相似文献
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以活性炭为载体通过浸渍一焙烧法制备了活性炭载铁(Fe/AC)催化剂,并考察了铁盐种类、煅烧温度、铁盐水溶液中铁离子浓度对催化臭氧化污泥的影响及处理后污泥的相关性质变化。结果表明.采用铁离子浓度为O.20mol·L^-1的FeCl3作为铁盐水溶液、煅烧温度为500℃所制备的活性炭栽铁催化剂催化臭氧化污泥的效果最佳;处理后污泥滤饼的含水率下降近9%,污泥滤液的COD值下降46.39mg·L^-1,污泥的沉降性能优于原污泥,滤液中的铁离子能更好地固化。XRD分析表明活性炭表面所负载的铁氧化物为Fe2O3。 相似文献
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A paired electrooxidative method has been developed to synthesize D-arabinose in a divided cell. D-arabinose is a material which has an important role in the production of vitamin B2 and DNA. Sodium gluconate was directly oxidized at the anode and indirectly oxidized in the catholyte by bubbling oxygen which was reduced to H2O2 and OH free radicals. In the catholyte, indirect oxidation of sodium gluconate was mediated by Fe3+ and OH free radicals. The optimal current efficiencies for D-arabinose production in the anolyte and catholyte were found to be 88.37% and 39.12%, respectively, and the total current efficiency of the paired electrooxidation was 127.49%. The paired electrosynthesis of D-arabinose is more economical in terms of power consumption than electrosynthesis that employ a single anode or cathode as the working electrode. The influence of cathodic/anodic CV and I/E curves, redox mediators and the amount of charge passed were also examined. 相似文献
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The effect of gluconate on the deposition rate and the deposit composition was examined at low pH of solution. The deposition rate exhibit a maximum and the content of copper present a minimum when the gluconate concentration changes between 0 and 40 g/l. The kinetic study carried out by cyclic voltammetry and electrochemical impedance showed that the gluconate acts on the anodic and cathodic reactions. The activation energy of the alloy deposition was determined. In addition, gluconate does not affect the crystallinity of the Ni-Cu-P deposit. 相似文献
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T. dos Santos C.I. Pereira R. Gonçalves V.R. Salvini C. Zetterström C. Wöhrmeyer C. Parr V.C. Pandolfelli 《Journal of the European Ceramic Society》2019,39(8):2748-2759
Considering the production of stable CAC aqueous suspensions, this work addressed the action of gluconate anion as a Ca2+ complexing agent and retarder of CAC hydration. Using quantum simulations, the complexation energy of gluconate complexes was calculated. The pH range of stability for the complexes was estimated and aqueous suspensions containing CAC and sodium gluconate (NaG), stable up to 4 days at room temperature, were prepared. Afterwards, their hydration reactions were reactivated by adjusting the systems’ pH. Results of solidification kinetics and mineralogical characterisation highlighted that, after reactivation, calcium aluminate hydrates were formed. Thermodynamics simulations indicated that using NaG up to 1 wt% would not be deleterious to the systems refractoriness up to 1700 °C. These systems could be applied in less explored processing routes for CAC-based refractory compositions (e.g. slip casting, direct foaming and additive manufacturing), resulting in innovations to produce advanced refractory ceramics. 相似文献
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文章采用了分光光度法测定葡萄糖催化氧化产物葡萄糖酸钠的含量,并与碘量法测定产品中残糖的含量进行比较。结果表明,采用分光光度法,操作简便易行,结果可靠,可作为葡萄糖催化氧化产物葡萄糖酸及其盐类的常规分析。 相似文献