...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of the Chilean Chemical Society >COMPARISON BETWEEN UV SPECTROPHOTOMETRY AND ANION EXCHANGE CHROMATOGRAPHY TECHNIQUES FOR QUANTIFICATION OF HEXENURONIC ACID (HEXA) IN UNBLEACHED KRAFT PULPS OF EUCALYPTUS GLOBULUS
【24h】

COMPARISON BETWEEN UV SPECTROPHOTOMETRY AND ANION EXCHANGE CHROMATOGRAPHY TECHNIQUES FOR QUANTIFICATION OF HEXENURONIC ACID (HEXA) IN UNBLEACHED KRAFT PULPS OF EUCALYPTUS GLOBULUS

机译：紫外分光光度法与阴离子交换层析技术定量分析真叶芥末草浆中正己酸（HEXA）的比较

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Two different methodologies were optimized for hexenuronic acid (HexA) quantification in E. globulus kraft pulps. In one, pulps were hydrolyzed with mercuric chloride/sodium acetate and quantified by ultraviolet spectrophotometry (UV technique); in the other one, the hydrolysis was performed with sulfuric acid and the degradation products of HexA quantified by anion exchange chromatography (AEC technique). In order to determine the optimal conditions for maximum removal of HexA from pulps by acid hydrolysis, the variables time, pH, and temperature were studied. The influences of these three variables were determined by means of a response surface methodology (RSM). The optimized conditions for the hydrolysis by the UV technique were: 45 mill, pH 5.7 and 80 degrees C. While, for hydrolysis using the AEC technique, the optimized conditions were: 3.1 h, pH 0.7 and 97 degrees C. Both AEC and UV methods presented good reproducibility with 2.1% and 1.4% relative standard deviation (RSD), respectively. However, HexA values measured by the AEC technique method were 11-30% lower than those measured using the UV technique. For additional information, five selected pulps were analyzed by other methods, known as KTH and HUT. The results obtained by the four methods employed showed significant variations in the HexA quantification. The highest HexA values were obtained using the UV technique. The KTH, AEC and HUT methods provided HexA amounts in 7-16%, 17-24% and 24-30% lower than the values obtained by UV method, respectively, for the same set of pulps. The UV technique is more susceptible to be interfered with pulp hydrolysis by products, attributed mainly to lignin solubilization, while the AEC technique allows direct measurement of HexA hydrolysis products without interference from other compounds.
机译：优化了两种不同的方法，用于在E. globulus牛皮纸浆中对己糖醛酸（HexA）进行定量。一种是将纸浆用氯化汞/乙酸钠水解，并通过紫外分光光度法（UV技术）进行定量。在另一种方法中，用硫酸进行水解，并通过阴离子交换色谱法（AEC技术）对HexA的降解产物进行定量。为了确定通过酸水解从纸浆中最大程度去除HexA的最佳条件，研究了变量时间，pH和温度。这三个变量的影响通过响应面方法（RSM）确定。通过UV技术进行水解的最适条件为：45磨，pH 5.7和80摄氏度。对于使用AEC技术进行水解的最适条件为：3.1 h，pH 0.7和97摄氏度。AEC和UV这些方法具有良好的重现性，相对标准偏差（RSD）分别为2.1％和1.4％。但是，通过AEC技术方法测得的HexA值比使用UV技术测得的HexA值低11-30％。有关其他信息，通过其他方法（称为KTH和HUT）分析了五种选定的纸浆。通过四种方法获得的结果显示出HexA定量的显着变化。使用UV技术可获得最高的HexA值。对于相同的纸浆，KTH，AEC和HUT方法分别提供的HexA量比通过UV方法获得的值分别低7-16％，17-24％和24-30％。 UV技术更容易受到纸浆水解产物的干扰，这主要归因于木质素的溶解，而AEC技术可以直接测量HexA水解产物而不受其他化合物的干扰。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号