常压微波消解分光光度法测定COD的研究

研究了常压微波消解分光光度法测定COD的方法,讨论了加热时间、硫酸银催化剂的用量、硫酸用量、硫酸磷酸的混酸体积比对微波消解法测定COD的影响.结果表明,微波加热60 s测定COD与国际标准测得COD基本一致,回收率达到96%;硫酸银用量对微波消解法影响不大,可实现无银催化,而硫酸用量不能减少;采用混酸代替硫酸后,V(硫酸):V(磷酸)=4:1时微波消解测定COD效果最佳.     

无催化微波消解法快速测定炼油污水中的化学需氧量

研究了无催化剂微波消解法测定炼油污水中的CODCr,详细考查了微波消解的有关条件,得到的最佳消解条件为:加入(S∶P=8∶1)混酸占总体积的55%,消解时间为12min,取样量为3.0mL,重铬酸钾溶液(浓度为0.15～2.0mol/L)3.0mL,功率720W。在最佳消解条件下跟踪一段时间,结果和回流法相符,相对误差在5%内。本法具有消解时间短,试剂用量少等优点,适合COD值在150～2000mg/L的炼油污水的测定。     

氧化铜（CuO）作催化剂测定废水化学需氧量(CODCr)试验

以CuO作为替代催化剂体系,协同硫磷混酸介质,探讨了无银催化法测定污水中化学需氧量(COD)的系列条件试验。结果表明测定最佳条件为CuO以粉末形式投加,投加量为0.05 g、硫酸∶磷酸(体积比)为5∶1、消解温度控制在160℃、消解时间为2 h,准确度、精密度与国标法有较好的可比性,其相对标准偏差为0.40%-0.58%。在实际废水测定中,与国标法测定结果比较,加标回收率为97.0%-103.3%。该方法完全可以成为常规实验室的适用方法。     

混酸催化甲醇液相合成二甲醚研究

研究了硫酸和磷酸混酸催化甲醇液相合成二甲醚过程。考察了混酸催化剂、反应温度、原料进料速率和催化剂寿命等对二甲醚收率的影响。实验结果表明,混酸催化剂能较好地催化甲醇液相脱水制二甲醚反应并可长期使用,当混酸催化剂的配比为w(硫酸)∶w(磷酸)=1.2∶1,反应温度为140℃,甲醇进料速度为1.00 mL/min时,二甲醚收率可达到84%。     

应用超声消解快速检测COD方法的实验研究

提出快速检测水样化学需氧量(COD)的新方法 ,即在常温常压下利用超声消解(UASD)水样,并结合分光光度法(SP)或氧化还原电位法(ORP)检测水样COD。实验表明,UASD法消解水样的最佳时间在4 min左右;用标准邻苯二甲酸氢钾溶液绘制工作曲线,采用UASD-SP法对污水样品的COD(经稀释COD500 mg/L)进行检测,测得的COD值与国标法测定值对比,准确度在-5.4%~-2.1%,实验精密度在0.42%~2.8%。实验证明了应用超声消解快速检测COD方法的可行性。     

籽瓜皮果胶的提取工艺研究

为探究提取分离新疆籽瓜皮中果胶的最佳工艺,采用酸提醇析法探讨了原料预处理、萃取剂的种类、浓度和加入量、萃取温度、时间和浓缩比例等因素对果胶产率的影响.运用正交实验确定最佳的工艺条件为:以细渣状沸水浴灭酶3 min,硫酸为萃取剂,萃取液pH值为1.5,料液比为1:15,萃取2次,萃取温度为90℃,萃取时间分别为2.5 h和1 h,浓缩比例为1/4,冷却后经1:1.5倍乙醇沉淀,果胶产率为19.5%.     

聚合氯化铝镁絮凝剂的制备及处理印染废水

以铝矾土、氧化镁粉和质量分数为20%的工业盐酸为原料,采用两段溶出工艺制备聚合氯化铝镁无机絮凝剂。通过正交实验考察了焙烧温度、焙烧时间、酸溶比例、酸溶时间和酸溶温度对氧化铝溶出的影响,确定了制备聚合氯化铝的最佳工艺条件。通过加入氧化镁粉提高产品盐基度得到聚合氯化铝镁絮凝剂。所得产品氧化铝含量9.6%,盐基度为46.3%。将该聚合氯化铝镁絮凝剂用于实际印染废水的处理,其COD和色度去除率比自制聚合氯化铝絮凝剂和市售聚合氯化铝絮凝剂均高出近20个百分点。     

高镁磷尾矿渣制取磷镁复合肥料的试验研究

采用正交试验设计方法组织实验，以确定磷、硫混酸制取磷镁复合肥料较优的工艺条件。研究结果表明，磷酸和硫酸的用量对混酸分解高镁尾矿渣的制取磷镁肥的影响比较显著，反应时间和反应温度影响较小。最佳工艺条件为：湿法磷酸用量95g，硫酸用量75g，反应时间30min，反应温度55℃，此时，MgO转化率为82．63％。     

高镁磷尾矿渣制取磷镁复合肥的工艺条件初步研究

介绍了以硫磷混酸和高镁磷尾矿粉为原料制备磷镁复合肥的工艺条件,并通过正交实验对其工艺条件进行优化。实验结果表明,最佳的工艺条件为硫酸用量15 g,磷酸用量110 g,反应温度50℃,反应时间20 min,此时P2O5、MgO转化率分别为91.34%和82.44%。     

硫磷混酸分解高镁尾矿渣制取磷镁复合肥的工艺条件研究

介绍了以硫磷混酸和高镁磷尾矿粉为原料制备磷镁复合肥的工艺条件,研究了硫酸用量、磷酸用量、反应时间和反应温度对五氧化二磷、氧化镁转化率的影响。通过单因素实验得到最佳的工艺条件:磷酸用量为110 g、硫酸用量为15 g、反应时间为20 min、反应温度为50℃。在此条件下,磷尾矿渣中五氧化二磷的转化率大于90%,氧化镁转化率大于80%。     

玻璃及其原料的化学分析方法现状简评

论述了玻璃及其原料的化学分析结果准确度在玻璃质量控制中的重要性,介绍了玻璃及其原料的标准化学分析方法,并将国内现行的国家标准或行业标准与国外先进国家同类标准进行了比较.     

Effect of aluminum-containing raw materials on the melting of borosilicate glass for fiber

Aluminum-containing raw materials for the synthesis of aluminum-borosilicate glasses for E-glass fiber should be rationally chosen to comprehensively assess their effect on the glass melting processes. The characteristic properties of the chemical, phase, and granulometric composition of the raw materials such as metallurgical alumina, non-metallurgical alumina, disthene, and kaolin were under study. It was revealed that the type of aluminum-containing raw materials significantly influenced the rate of glass formation processes and heat consumption required for these processes. The efficiency of aluminum-containing raw materials is influenced by the following factors: the phase composition, which determines the sequence and rate of phase transformations, as well as the heat-absorbing ability of the furnace batch and glass melt. The most energy-efficient material is non-metallurgical alumina of the White Alumina brand. Using it facilitates saving energy resources for glass formation processes from 2.64% to 16.30% as compared with other types of aluminum-containing raw materials. The use of kaolin proves to be the least efficient due to the additional energy consumption for the process of destruction of the crystal structure of kaolinite, the reduced thermal conductivity of the batch, and the thermal transparency of the borosilicate glass melt.     

Use of Technogenic Raw Materials of the Mining Plants of Murmansk Region for Manufacturing Glass and Glassy-Crystalline Materials

The main conditions for obtaining decorative glass and glassy-crystalline materials from technogenic raw materials (overburden rocks, enrichment wastes, by-products of processing ores and concentrates, wastes of chemical industries) are considered. Relationships between the composition of the secondary raw materials and a number of important technological properties are established. The compositions and conditions of the production of decorative glass and glass with special properties made of technogenic raw materials from Murmansk region are developed. The efficiency of the compaction of glass batches is studied and the increase in the melting speed of the tableted batch and the clarification rate of the glass mass are experimentally observed.     

Use of secondary resources for increasing the chemical stability of glass enamels

The chemical stability of glass enamels obtained with available synthetic and close to synthetic raw materials is investigated. The charge and chemical compositions of two enamels based on available raw materials are presented. The developed enamels are recommended for the chemical and metallurgical industries as acid-resistant coatings.Translated from Steklo i Keramika, No. 10, pp. 30 – 32, October, 1995.     

低介电常数NaF-ZnO-P_2O_5-B_2O_3玻璃的研究

低介电常数材料分为有机和无机低介电常数材料,含氟低介电常数材料主要应用于电子行业,可以降低集成电路的漏电电流、导线之间的电容效应和集成电路发热等。选定氧化锌、氧化磷、氧化硼以及氟化钠作为低温低介电常数玻璃的原料,研究了不同ZnO、B2O3配比下的玻璃样品的介电性能和耐水性能,结果表明,随着ZnO摩尔分数的增加,材料的介电常数有所下降;随着B2O3摩尔分数的增加,材料的耐水性能有所下降。     

电磁屏蔽玻璃的生产和质量控制

电磁屏蔽玻璃的制作是采用夹层玻璃的工艺完成的.各种材料的清洗、蒸压时的温度制度、金属丝网的化学浸镀等都会造成产品质量问题.只有严格挑选材料、严格工艺制度,从细微处入手,才能逐步提高产品的成品率.     

用铬渣为主要原料制备微晶玻璃

本文介绍了用铬渣为主要原料制备微晶玻璃的方法，用ＤＴＡ、ＸＲＤ和ＯＭ观察和分析了该材料的晶相和显微结构，并对其主要理化进行了测试。     

基于Rietveld法TOPAS定量分析在玻璃原料中的应用研究

以XRD为工具,对玻璃原料进行定性分析,运用TOPAS软件对其进行定量分析研究,考察TOPAS定量分析的应用可能性。结果表明,基于Rietveld法的TOPAS定量分析对于玻璃原料的物相鉴定很有意义,无需标样校正,可用于多相复杂的粉末谱相定量,不因物相的增多、衍射峰重叠而发生困难,解决化学分析仅能辨别氧化物组成的劣势,且比传统的定量分析手段更简便。     

Prompt Calculation and Correction of the Glass Batch Formula

A new program for the calculation of a glass batch formula has been developed that accelerates and improves the calculation process, makes it possible to simulate the variation of the glass composition with the chemical composition and ratio of raw materials, and quickly perform multiple recalculations of different variants.     

Andalusite: An amazing refractory raw material with excellent corrosion resistance to sodium vapours

The chemical attack of alumina refractories by sodium vapours is far from been completely understood. In order to contribute to a better knowledge of this attack, a laboratory test was developed to simulate the sodium gaseous corrosion of different raw materials and refractories.Corrosion of alumina raw materials by sodium vapours is due to a dissolution–precipitation process by a Na₂O rich liquid phase. The gaseous corrosion strongly depends on the microstructures and the assemblage of phases in alumina raw materials. Fire clay and andalusite raw materials exhibit very high corrosion by Na vapours. In spite of an initial high silica glass content, and as a result of trapping of the main part of the glass in the capillary network of the mullite composite crystal, mullitised andalusite leads to excellent corrosion resistance which is close to monocrystalline fused mullite.Consequently, The use of mullitised andalusite particles in the matrix of alumina refractories limits the liquid phase formation during corrosion by sodium gas. These experimental results are in agreement with thermodynamic calculations.