Gradient✓ (GradientCheck) for Heterogeneous Catalysis:

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Open JSON Input File Fill Form from File

Reaction Phase:	Gas PhaseLiquid Phase / default: Gas Phase
Temperature (Tb & Tw):	/ K
Pressure (P):	/ bar
Reactor Radius (Rr):	/ m -- [Accepts scientific notation e.g. 1e-3]
Bed Length (Lb):	/ m
Catalyst Particle Shape:	Spheres Cylinders Rings
Particle Radius (Rp):	/ m
Particle Length (Lp):	/ m
Inner Radius (Rp,inner):	/ m (must be < Rp)
Observed Reaction Rate (robs):	/ moles of A × kg-cat-1 × s-1
Enthalpy of Reaction (ΔHrxn)	/ J × mole-1
Reaction Order (n)	0 1 2
Activation Energy (Eapp)	/ J × mole-1
Conversion (XA)	/ unitless (0 to 1)
Catalyst Bulk Density (ρbulk):	/ kg × m-3 [usually 500-1500]
Catalyst Void Fraction (ε):	/ (0 to 1) [often 0.35-0.45 (default 0.4)]
Catalyst Thermal Conductivity (kp):	/ W × m-1 × K-1 [often 0.13-0.25]
Catalyst Surface Area (Sint):	/ m2 × g-1
Catalyst Pore Volume (Vpore):	/ m3 × g-1
Catalyst Pore Tortuosity (τ):	/ unitless [often 3-7 for porous catalysts]
Initialize:

Number of Reactants:

OneTwo

Number of Products:

OneTwo

	Main Reactant A	Product B	Diluent C
Inlet Mole Fractions:						/ must add to 1
Fluid Viscosity (μf):						/ kg × m-1 × s-1
Heat Capacity (Cp):						/ J × kg-1 × K-1
Thermal Conductivity (kf):						/ W × m-1 × K-1
Diffusion Volume (Σν,i):						Estimate Σν,i
Liquid Density (ρf):						/ kg × m-3
Molar Volume (Vb,i):						Estimate Vb,i
Association Factor (φAi):						φAi Help
Molecular Weight (MW):						/ g × mol-1

Notes:

+  Advanced Option

	Override Estimate of Effective Diffusivity (Deff):		/ m2 × s-1

Output Filename:.json Download Form

	Reactant A	Product B	Diluent C
Ideal Gas Density:						/ kg × m-3
Inlet Concentration of A:		/ mol × m-3
Is "A" The Limiting Reactant?

+
Mixture Diffusivity (DAm):	/ m2 × s-1
Average Molecular Weight (MW):	/ g × mol-1
Average Heat Capacity (Cp):	/ J × kg-1 × K-1
Average Thermal Conductivity (kf):	/ W × m-1 × K-1
Average Viscosity (μf):	/ kg × m-1 × s-1
Average Density (ρf):	/ kg × m-3
+
Total Mass Flow Rate (ṁ):	/ kg × s-1
Superficial Mass Flux (G):	/ kg × m-2 × s-1
Space Time Across Bed (tbed):	/ s
Catalyst Mass Loaded (mcat):	/ kg
Catalyst Bed Volume (Vbed):	/ m3
Particle Porosity (εp):	/ (0 to 1) [usually 0.3-0.7]
Particle Density (ρp):	/ kg × m-3
Mean Pore Radius (rpore):	/ Å
Single Particle Volume (Vp):	/ m3 × particle-1
External Surface Area (Sext):	/ m2 × particle-1
External Surface Area Per Mass (am):	/ m2 × kg-1
+
Reynolds Number:	/ unitless
Prandtl Number:	/ unitless
Schmidt Number:	/ unitless
Chilton-Colburn Factor (jD):	/ unitless
Mass Transfer Coefficient (km):	/ m × s-1
Sherwood Number:	/ unitless
Particle-Fluid Heat Transfer Coefficient (h):	/ W × m-2 × K-1
Nusselt Number:	/ unitless
Effective Diffusivity (Deff):	/ m2 × s-1

+
	Bed Average	Bed Inlet	Bed Outlet
Weisz-Prater Modulus (MWP):				/ unitless
Thiele Modulus (MT):				/ unitless
Effectiveness Factor (η):				/ unitless

External Concentration Gradient:	/ %
External Temperature Gradient:	/ K
Internal Temperature Gradient:	/ K
Prater Number (β):	/ unitless
Intrinsic (1st Order) Rate Constant (kint):	/ m3 × kg-cat-1 × s-1
Max Possible Diffusion-Limited Rate (rmax):	/ moles of A × kg-cat-1 × s-1
External Surface Concentration:	/ mol × m-3
External Surface Temperature:	/ K

Axial Dispersion Coefficient (Daxial):	/ m2 × s-1
Radial Dispersion Coefficient (Drad):	/ m2 × s-1
Pressure Drop Across Bed (ΔP):	/ bar
Effective Radial Thermal Conductivity (kre):	/ W × m-1 × K-1
Wall Heat Transfer Coeff (hw):	/ W × m-2 × K-1
Internal Heat Transfer Coeff (hi):	/ W × m-2 × K-1
Axial Temperature Change (ΔTaxial):	/ K

robs < rmax		Is the observed reaction rate realistic?
∑ yi = 1		Do the mole fractions add to one?
0.25 < ε < 0.55		Is the void fraction within typical range?
0.1 < kp < 1		Is the particle conductivity within typical range?
εp < 0.7		Is the porosity within typical range?
2 < τ < 6		Is the tortuosity within typical range?
0.5 < Pr < 1.5		Is the Prandtl number within typical range for a gas?
ReLiq > 0.01 or ReGas > 1		Is the Reynolds number within the valid range for j-factor correlations?
β > 0.3		Are multiple steady states possible?
(Cb - Cs)/Cb > 5%		Does external diffusion limit reaction rate?
(Cb - Cs)/Cb > 50%		Does external diffusion control reaction rate?
|Tb - Ts| > 1 K		Is the external temperature gradient significant?
|Ts - Tc| > 1 K		Is the internal temperature gradient significant?
η < 0.95		Does pore diffusion limit reaction rate?
η < 0.5		Does pore diffusion strongly affect reaction rate?
ΔP > 0.2P		Is the bed pressure drop greater than 20% of the total pressure?
+Mears Axial Dispersion		Does axial dispersion have a large effect upon rate?
LHS	≤	RHS ?
+Gierman Axial Dispersion		Does axial dispersion have a large effect upon rate?
LHS	≤	RHS ?
+Sie Wall Effects		Do broad radial velocity profiles negatively effect the reactant RTD?
LHS	≤	RHS ?
+Mears Radial Interparticle		Does a radial interparticle heat transport limitation indicate a nonisothermal reactor?
LHS	≥	RHS ?