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Study on the Determination Method of Elemental Silicon and Silicon Dioxide in Calcium-Aluminum-Silicon Alloy

Author(s)

Lv Jiaojiao, Wang Bin

Affiliation(s)

Ningxia Jianlong Special Steel Co., Ltd., Shizuishan, Ningxia, China

Abstract

Aiming at the problem that elemental silicon (Si) and silicon dioxide (SiO2) coexist in calcium--aluminum-silicon alloy and are difficult to directly distinguish and determine, a combined determination scheme of "dilute alkali-weight method+molybdenum blue spectrophotometry" is proposed. Elemental silicon is dissolved by dilute sodium hydroxide solution, while silicon dioxide is insoluble in dilute alkali, and then the two are separated by filtration; the filtrate is acidified, and elemental silicon is determined by weight method+molybdenum blue spectrophotometry; the residue is treated by alkali fusion and acidification, and silicon dioxide is determined again by weight method+molybdenum blue spectrophotometry. the experimental results show that the standard addition recoveries of elemental silicon and silicon dioxide by this method are 99.56%~100.40% and 99.61%~100.08% respectively, and the relative standard deviations (RSD) are all less than 1.40%. It can effectively avoid the interference of aluminum and calcium elements in the matrix, and realize the accurate separation and quantification of the two forms of silicon.

Keywords

Silicon–Aluminum–Calcium Alloy; Elemental Silicon; Silicon Dioxide; Dilute-Alkali Separation; Gravimetry–Molybdenum Blue Spectrophotometry.

References

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