Quantitative analysis of slurry cement powder injection based on microwave plasma torch

Abstract The elements of Mg, Al, Ca, and Si in cement were quantitatively analyzed by slurry powder injection microwave plasma torch emission spectrometry (MPT-OES). Through the comparative test of powders with different particle sizes, 40 μm powder was selected to configure 0.05% m/v slurry, and 0.01% m/v glycerol + 1% v/v HCl was selected as a dispersant. Based on the principle of the Babington nebulizer, a slurry nebulizer with a good atomization effect was designed and fabricated to meet the experimental conditions, and the atomization efficiency was 3.28%. The slurry was stabilized by ultrasonic shaking for 20 min before injection, and the MPT light source was introduced through the nebulization chamber through a peristaltic pump (0.2 mL/min). The oxygen shielding gas was 1.2 L/min, the argon maintenance gas was 0.6 L/min, and the argon carrier gas was 0.2 L/min. The mass concentrations of Mg, Al, Ca, and Si were 2.85∼10.92, 17.96∼34.76, 192.11∼211.00, and 9.38∼54.81 μg/mL, respectively, and the intensity in the concentration range was linear. The linear correlation coefficients were greater than 0.997, and the relative standard deviations were 1.14%-4.56% (n=50). The results show that this method has a good detection effect under different powers, and has a good application prospect in the online detection of solid powders.