Rate Equation of Reactant A in G/L Reactions Calculator

Reaction Rate Formula:

\[ r_A''' = \frac{1}{\left(\frac{1}{k_{Ag}a_i} + \frac{H_A}{k_{Al}a_i} + \frac{H_A}{k_{Ac}a_c} + \frac{H_A}{k_A''' C_{B,d} \xi_A f_s}\right)} p_{Ag} \]

Gas Phase Mass Transfer Coefficient (k_Ag):

m/s

Inner Area of Particle (a_i):

1/m

Henry Law Constant (H_A):

mol/(m³·Pa)

Liquid Phase Mass Transfer Coefficient (k_Al):

m/s

Film Coefficient of Catalyst on A (k_Ac):

m/s

External Area of Particle (a_c):

m²

Rate Constant of A (k_A'''):

1/s

Diffused Concentration of Reactant B (C_B,d):

mol/m³

Effectiveness Factor of Reactant A (ξ_A):

Solid Loading into Reactors (f_s):

Pressure of Gaseous A (p_Ag):

Reaction Rate of Reactant A (r_A'''): mol/(m³·s)

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Rate Equation of Reactant A in G/L Reactions?

Definition: This equation calculates the reaction rate of reactant A in gas-liquid reactions considering mass transfer resistances in gas film, liquid film, and catalyst surface, along with the intrinsic reaction rate.

Purpose: It helps chemical engineers design and analyze gas-liquid-solid catalytic reactors by accounting for all mass transfer limitations and the actual reaction rate.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ r_A''' = \frac{1}{\left(\frac{1}{k_{Ag}a_i} + \frac{H_A}{k_{Al}a_i} + \frac{H_A}{k_{Ac}a_c} + \frac{H_A}{k_A''' C_{B,d} \xi_A f_s}\right)} p_{Ag} \]

Where:

\( r_A''' \) — Reaction rate of A per unit volume of catalyst (mol/(m³·s))
\( k_{Ag} \) — Gas phase mass transfer coefficient (m/s)
\( a_i \) — Inner area of particle (1/m)
\( H_A \) — Henry's law constant (mol/(m³·Pa))
\( k_{Al} \) — Liquid phase mass transfer coefficient (m/s)
\( k_{Ac} \) — Film coefficient of catalyst on A (m/s)
\( a_c \) — External area of particle (m²)
\( k_A''' \) — Rate constant of A (1/s)
\( C_{B,d} \) — Diffused concentration of reactant B (mol/m³)
\( \xi_A \) — Effectiveness factor of reactant A
\( f_s \) — Solid loading into reactors
\( p_{Ag} \) — Pressure of gaseous A (Pa)

Explanation: The formula accounts for resistances in series: gas film, liquid film, catalyst surface film, and the actual reaction rate.

3. Importance of Reaction Rate Calculation

Details: Accurate reaction rate estimation is crucial for reactor design, process optimization, and scaling up chemical processes from lab to industrial scale.

4. Using the Calculator

Tips: Enter all required parameters with appropriate units. Default values are provided for reference but should be replaced with actual experimental or literature values for your specific system.

5. Frequently Asked Questions (FAQ)

Q1: What if I don't know some of these parameters?
A: You may need to perform separate experiments or consult literature to estimate missing parameters. Some can be calculated from correlations.

Q2: How do I determine the effectiveness factor?
A: The effectiveness factor can be estimated from Thiele modulus calculations or measured experimentally.

Q3: What's a typical range for Henry's law constant?
A: It varies widely depending on the gas and liquid. For common gases in water at 25°C, it ranges from 1.3×10⁻⁵ (H₂) to 3.3×10⁻⁴ (CO₂) mol/(m³·Pa).

Q4: How does temperature affect this calculation?
A: Temperature affects all rate constants and mass transfer coefficients. Use values appropriate for your operating temperature.

Q5: Can this be used for non-catalytic G/L reactions?
A: For non-catalytic reactions, omit the catalyst-related terms (k_Ac and effectiveness factor).