High-frequency infrared carbon and sulfur analyzer reduces and stabilizes the blank value. We used it for the initial measurement and the second measurement. If necessary, for the third measurement, we can get the sulfur blank value. The results show that the method has high precision and accuracy.
High-frequency infrared carbon and sulfur analyzer is controlled by computer and is suitable for the determination of sulfur content in metals, ores and other materials. It consists of a detection unit and a WT-88 infrared induction high frequency burner, including a computer system, an electronic balance, two independent measurement channels and a detection unit. Since blank values are related to many factors, conventional devices cannot eliminate the effects of blank values. When we measure low sulfur materials, if we do not eliminate the blank value, it will cause a large error. Therefore, it is very important to measure the blank value.
Due to the many factors affecting the determination of sulfur, there is currently no simple case operation method to measure the blank value. Our measurement methods are experimental based and can be used in routine measurements. The importance of the method of operation is 2 to 3 cycles, which we call the cyclic measurement of the sulfur blank value.
There is no blank value in the sample, which is determined by the experimental environment and experimental flux under the same analytical conditions. In the actual analysis, flux, analytical gas path, helium, oxidant, etc. are the main sources of blank values. The desiccant, the dust in the combustion tube, the combustion passage and the burning time have a certain influence on the blank value and stability.
In the actual analysis process, we can't control every source of the blank value, but we can reduce the blank value to make it stable. We can choose low-vacuum fluxes, bismuth and pure oxygen. Tungsten is a flux with the lowest margin. When we add flux every time, we must accurately weigh, especially pure iron flux.
We need to keep the desiccant dry in order to purify the carrier gas more efficiently and avoid the effects of water. Since SO2 is soluble in water to form H2SO3, water vapor and SO2 have close absorption lines in the infrared, thus interfering with the determination of sulfur content.
The burner needs to be kept clean. We found that the longer the instrument's working time and the analysis of wet samples containing high sulfur, the greater the system's blank value. Since it produces a powdery basic oxide during the melting process, it has a strong adhesion to the gas, resulting in a lower result. When saturated, the gas will slowly release and the result will be high. In order to get a stable blank value, we must always clean the furnace, pipes and filters.
