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《中国石油和化工标准与质量》2017,(12)
己二酸也就是肥酸,是一种有机二元酸,其作用是成盐反应、酯化反应、酰化反应等,同时也能够与二元胺与二元醇缩聚成高分子聚合物。己二酸在工业、医药、化工等领域中得到广泛的应用。当前,国内己二酸行业产能过剩,竞争激烈,一方面是在产品价格上的竞争,另一个更为主要的方面是产品质量的提高。己二酸质量主要受制于硝酸根和水分这两个指标,为此,加强己二酸产品质量的分析,尤其是对硝酸根和水分影响因素分析,采取针对性措施,对提高己二酸产品质量有举足轻重的作用。文中将对己二酸的当前质量标准进行阐述,分析影响己二酸质量的具体因素,并提出改进措施。 相似文献
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《合成纤维工业》2016,(5):70-73
为了探究己二酸生产过程中影响己二酸产品质量的微量杂质并加以控制,采用GC/MS-TQ8030气相色谱-质谱联用仪分析了环己烯水合法生产己二酸时中间产物环己醇中的杂质,采用酯化萃取与中和萃取的方法,分别对环己烯和环己醇重组分氧化产物以及己二酸结晶母液和己二酸产品进行了考察。结果表明:环己醇中的主要杂质为环己烯和环己醇重组分,环己烯硝酸氧化产物能够确定的有12种,影响己二酸的纯度,且氧化液颜色为深褐色,给后续吸附脱色造成困难,实际生产中应控制环己醇中环己烯含量低于100mg/kg;环己醇重组分硝酸氧化产物能够确定的有36种,且多为不溶于水的化合物,影响己二酸的色度,实际生产中应控制环己醇重组分含量低于500 mg/kg;己二酸结晶母液和己二酸产品中均检测到苯酚,反应器散热效率低,微量苯酚难从己二酸体系中分离是导致己二酸中微量苯酚存在的原因,实际生产中采用6台反应器串联,当1#,2#,3#反应器投料量占总投料量的70%,且3个反应器温度控制在80℃以下时,己二酸产品中苯酚等杂质明显下降。 相似文献
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灰分、硝酸盐含量是影响精己二酸产品质量的主要参数,在实际生产过程中,对影响上述参数的因素进行研究,通过改造空气过滤器、调整离心机的操作参数等手段,控制己二酸产品灰分及硝酸盐含量,实现产品质量优化的目的。 相似文献
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分光光度法测定轻质碳酸钙中硝酸根含量 总被引:1,自引:0,他引:1
轻质碳酸钙中含有杂质硝酸根,其含量是影响轻质碳酸钙产品质量的一个重要指标,用水杨酸钠分光光度法测定轻质碳酸钙中的硝酸根,建立了一个简单、快速、选择性好的轻质碳酸钙产品中硝酸根的测定方法。在410 nm波长处,硝酸根质量浓度在0.50~2.50 mg/L时与水杨酸钠吸光度呈线性关系,线性回归方程为y=0.102 2x+0.002 7,r=0.999 35,相对标准偏差优于10%,加标回收率在93%~104%,可用于测定轻质碳酸钙产品中硝酸根含量,操作简单,可行性强,可以满足测定要求,应用于实时监控。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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The miscibility of various amorphous polybutadienes with mixed microstructures of 1,4 addition units (cis, 1,4 and trans 1,4) and 1,2 addition units have been investigated. The studies here involved optical transparency, differential scanning calorimetry, and small angle light scattering. It was found that a 90 percent (cis) 1, 4 addition polybutadiene was immiscible with high (91 percent) 1,2 addition polybutadiene. Reduction of the 1,2 content to 71 percent induced an upper critical solution temperature (UCST) with the cis 1,4 polymer. Polybutadienes with 50 percent and 10 percent 1,2 contents were miscible above the crystalline melting temperature of the cis 1,4 polybutadiene. Immiscibility of the 91 percent 1,2 addition polymer was also found with a 10 percent 1,2 polybutadiene. The latter polymer also exhibits an UCST with the 71 percent 1,2 polymer. The results are used to interpret the characteristics of blends of polybutadienes of varying microstructure. 相似文献
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以F类粉煤灰为例,详细介绍了测定粉煤灰中烧失量的步骤、计算数学模型、影响测量不确定度的因素以及各项测量不确定度分量评定,人员、设备、材料、方法、环境都是影响测量不确定的因素。 相似文献
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我厂3号回转窑(Φ4m×60m)生产线在1996年年底由SP窑(产量912t/d)改为NSP窑(产量1320t/d),预分解系统为四级旋风预热器带离线式分解炉 相似文献
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Conclusions It is significant that the purification on a single passage of viscose through porous ceramic corresponds to the result of a two-stage filtration of it in industrial filter-presses with standard fillings.Kiev Combine. Kiev Technological Institute of Light Industry. Translated from Khimicheskie Volokna, No. 3, pp. 20–22, May–June, 1969. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献