摘要
游离碳是熔盐氯化重要反应物之一,对二氧化钛氯化反应速率影响较大,准确测定熔盐中游离碳含量,对控制氯化反应及炉料添加有重要指导意义。氯化熔盐属高氯样品,目前用管式炉或高频炉燃烧,红外吸收法测定熔盐中碳含量时,存在无相应标准样品建立仪器标准工作曲线和燃烧产生的氯气易腐蚀仪器的问题。实验提出用氯化钠稀释石油焦标准样品,配制不同浓度的游离碳校准样品,同时对仪器试剂管改装,以石英砂-氢氧化钙(m_(石英砂)∶m_(氢氧化钙)=3∶1)吸收氯气,有效解决上述问题,实验还讨论了燃烧温度、氧气压力、样品量对游离碳测定的影响。实验结果表明:当样品量为0.15 g,燃烧温度700℃、氧气压力0.50 MPa时为氯化熔盐中游离碳的最佳测量条件。采用实验方法对生产过程中氯化熔盐样品及配制的校准样品测量,方法精密度小于2.0%,校准样品测量值与理论值在实验允许误差范围内。
Free carbon is one of the important reactants in molten salt chlorination,which has a significant impact on the rate of titanium dioxide chlorination reaction.Accurately measuring the content of free carbon in molten salt is of great guiding significance for controlling chlorination reaction and furnace charge addition.Chlorinated molten salt belongs to high chlorine samples.Currently,when using tube furnaces or high-frequency furnaces for combustion,there are problems with the lack of corresponding standard samples to establish instrument standard cost curves and the corrosion of instruments caused by chlorine gas generated by combustion when determining the carbon content in molten salt using infrared absorption method.The experiment proposed diluting petroleum coke standard samples with sodium chloride to prepare calibration samples of different concentrations of free carbon.At the same time,the instrument reagent tube was modified to absorb chlorine gas with quartz sand calcium hydroxide(3∶1,mass ratio),effectively solving the above problems.The experiment also discussed the effects of combustion temperature,oxygen pressure,and sample size on the determination of free carbon.The experimental results indicate that the optimal measurement conditions for free carbon in chloride molten salt are when the sample size is 0.15 g,the combustion temperature is 700℃,and the oxygen pressure is 0.50 MPa.Experimental methods were used to measure the chloride molten salt samples and calibration samples prepared during the production process.The precision of the method was less than 2.0%,and the measured values of the calibration samples were within the allowable error range of the experiment.
作者
王勇
施宗友
刘林
Wang Yong;Shi Zongyou;Liu Lin(National Quality Supervision and Inspection Center of Vanadium and Titanium Products,Panxi Institute of Vanadium and Titanium Inspection and Testing,Panzhihua 617000,China)
出处
《山东化工》
CAS
2024年第11期175-177,198,共4页
Shandong Chemical Industry
关键词
富氧燃烧
红外吸收
氯化熔盐
游离碳
oxygen rich combustion
infrared absorption
chlorinated molten salt
free carbon
