Abstract: Gas-liquid precipitation reactions in terms of a spray exist widely in energy, chemical, and environmental engineering. In this paper, a rainbow refractometry-based method is used to measure the reaction process of these spray-based gas-liquid precipitation reactions in a non-intrusive way. Rainbow refractometry can simultaneously provide information on thermochemical and physical properties of droplets. A global rainbow measurement system was built to characterize a CO₂ absorption reaction. Rainbow signals of spray droplets of Ca(OH)₂ solutions before and after CO₂ absorption were recorded and processed. Results indicated that the average refractive index of saturated H₂O-Ca(OH)₂ solution was 1.335 69, which accorded with the Abbe measurement. After the absorption reaction, the refractive index of droplets decreased to 1.335 17 which is close to that of water. The reaction extent was therefore reflected in the change of the refractive index of droplets. An extra experiment of CO₂ absorbed by Ba(OH)₂ solutions was conducted. The refractive index of droplets decreased with the reaction process, which acted well as an evolution indicator of the reaction. A heat transfer analysis of the reaction was also carried out. Due to the high heat dissipation performance of fine droplets, the temperature increase in the measurement volume was estimated to be less than 0.61 K, which has almost no effect on the measured results. The rainbow refractometry-based method shows good potential for in-situ characterization of a gas-liquid precipitation reaction.

Key words: Rainbow refractometry; In-situ characterization; Refractive index; Gas-liquid precipitation reaction

Please provide your name, email address and a comment

Your Name: Affili: E-Mail Address:

Comment (Please comment in English):


Verification Code(click to change a pic):