//Harriot P., 2003, Chemical Reactor Design (I-Edition), Marcel Dekker, Inc., USA, pp 436. //Chapter-8 Ex8.2 Pg No. 329 //Title:External Mass Transfer resistance //=========================================================================================================== clear clc //INPUT Chi=1.9; M_A=2;//Molecular weight of Hydrogen M_B=32;//Molecular weight of methanol rho=0.79;//Density of methanol myu=0.52;//Viscosity of methanol (cP) V_A=14.3//Molar volume H2 T_C=30;//Operating Temperature(°C) T_K=273+T_C//Temperature (K) Epsilon=0.4;//Porosity rho_cat_dry=1.2;//Density of dry catalyst (g/cm3) rho_s=2;//Solid density g=9.8// Acceleration due to gravity(m/s2) d_p=10^(-3);//Size of catalyst (cm) lambda=1.3;//From equation 8.4 Pg. No. 317 r_vol=2.4;//Measured rate (L/min) V_mol=22.4;//(L/mol) assuming ideal gas C_H2=4.1*10^(-3);//From Figure 8.3 (mol/L) Pg. No. 321 //CALCULATION //Assume D_H2 is three times the value given by the Wilke–Chang Equation D_H2=3*(7.4*(10^(-8))*(Chi*M_B)^(0.5)*T_K)/(myu*(V_A)^0.6) Sc=myu*10^-2/(rho*D_H2); rho_cat_methanol=(1-Epsilon)*rho_s+Epsilon*rho; delta_rho=rho_cat_methanol-rho; v_t=(g*10*(d_p)^2*delta_rho)/(18*myu*10^-2);// From Stoke's Law Re=rho*v_t*d_p/(myu*10^-2); Sh_star=2+0.6*(Re)^(0.5)*(Sc^(1/3));//Refer equation 8.9 Pg.No.325 kc_star=Sh_star*D_H2/d_p; kc=2*kc_star;//With vigorous agitation a_c=6*lambda/(d_p*rho_cat_dry);//From Equation 8.4 Pg. No. 317 r_mol=r_vol/(22.4*60);// delta_C_ext=r_mol*10^3/(kc*a_c); percent_ext_resistance=(delta_C_ext/C_H2)*100; //OUTPUT mprintf('\nThe external mass transfer resistance is about %0.0f%% of overall resistance',percent_ext_resistance); mprintf('\n The external mass transfer resistance is barely significant'); //FILE OUTPUT fid= mopen('.\Chapter8-Ex2-Output.txt','w'); mfprintf(fid,'\nThe external mass transfer resistance is about %0.0f%% of overall resistance',percent_ext_resistance); mfprintf(fid,'\n The external mass transfer resistance is barely significant'); mclose(fid); //=====================================================END OF PROGRAM=========================================