An efficient empirical model for microwave-induced average temperature of liquid cylindrical reactants

Area of Science:

• Chemical Engineering
• Physical Chemistry
• Process Chemistry

Background:

• Microwave-assisted synthesis offers advantages like faster reactions and higher yields.
• The thermal effects in microwave reactors are often unclear due to their "black box" nature.

Purpose of the Study:

• To develop a simple mathematical model for calculating microwave-induced temperature in a cylindrical reactor.
• To quantify the thermal effects in microwave-assisted chemical processes.

Main Methods:

• A mathematical model was developed for a three-media cylindrical structure simulating a microwave reactor.
• The model computes average reactant temperature based on absorbed microwave power and heating time.
• Convection flows were assumed for stirred reactants.

Main Results:

• The model successfully computed time-temperature profiles for water, ethanol, and methanol.
• Calculated temperature curves for water showed excellent agreement with experimental data.
• The results support the hypothesis of temperature homogenization in liquid reactants due to convection.

Conclusions:

• The developed mathematical model aids in understanding and quantifying microwave-assisted chemical processes.
• Convection plays a significant role in homogenizing temperature in liquid reactants within batch reactors.
• This modeling approach can clarify the thermal dynamics of microwave heating in chemical synthesis.