Calculating the parameters of linear pseudo first order and second order kinetic of all forms are easy. But without any software calculating the parameters of nonlinear pseudo first order and second order kinetic from their equations by using excel sheet is difficult. Any any one help me to resolve the problem?
Please, Shanti, let me know to which process do you want to apply kinetics.
Adsorption is different from desorption. Reaction kinetics in liquid environment are different from solid or gaseous environment. Can you specify your question?
Thank you sir for giving the interest in my question.
I want to know the adsorption kinetics of adsorbate (in solution form) to the adsorbent (solid form) during adsorption process in normal tempearture. And the equations that am using for the adsorption kinetics are as follows. In both the equation I want to find the parameters through excel sheet.
Non-linear Pseudo first order kinetic: qt= qe (1-e^(-K1 t), plot between qt vs. t
Non-linear Pseudo second order: qt= (K2 qe^(2 ) t)/(1+ K(2) qe t), plot between qt vs. t
Dear Shanti, please find here enclosed the excel file we are using.
I hope it can be useful for your applications
Do not hesitate to contact me for explanations
Have a great WE
Sabino
Hello,
you can use Origin software of Microcal and use non-linear regression method, you have the choice between simplex algorithm and levenberg marquardt algorithm.
best regards
Plot the graph in origin soft ware after programming the equation and find the values for the slope and intercept from which calculate your required parameters.
ok.. In micro-soft excel also by putting the values of qt and t we can plot the linear equation and get the slope and intercept values. but from that values how can I get the unknown parameters of non linear pseudo second order equation. Because we can not simplify the nonlinear pseudo second order equation to linear pseudo second order equation.
Non-linear Pseudo second order equation is
qt= (K2 qe^(2 ) t)/(1+ K(2) qe t)
After getting the values of slope and intercept from graph how can I put it to the above equation to get the values of K2 and qe without simplify the equation.
Dear Shanti,
second order equations, as well as exponential ones, should be linearized to calculate the equation parameters. The linearization is a mathematical well defined method that does not alter the results needed with very good approximation. I sent you the excel file we are using, if you have difficulties send me data and I will elaborate them for you. In my file I used d for qt and D for qe, but my second order equation is perfectly equal to yours.
Hello to all,
I'm facing also some kind of a similar problem.
I'm using origin software for my kinetics but i can't make work all the models.
With pseudo second order everything good but when comes to pseudo first or elovich no. More I need your help for pseudo first. Is anyone familiar to help me, please?
I'm attaching you a screenshot of what I wrote as function and as parameter settings and how the fitting become.
I will really appreciate it if you help me.
With Regard
Do the programming the equations in origin software and put the data to draw the graph which will give the value of slope and intercept. These values shall be used for the calculation of parameters.
In all other equations as isotherms and pseudosecond order i didnt have to.. It was giving me automatic. Should i calculate them for non linear pseudo first order?
How do i calculate them? From linear form?
Hello,
can anyone help me in parameter setting for the pseudo-second-order kinetic model in origin pro? I need to perform non-linear fitting
Dear Ms. Kar,
You may use mycurvefit software available on internet which allows free use after registration for some limited data sets. You can choose own equation as per the requirement of non-linear kinetic equations to obtain the values of intercept and slope parameters beside coefficient of determination and standard error of prediction. Please take care in fitting the correctly typed equation and fill in the x and y values in the colums provided.
P. C. Srivastava
This video step by step shows how to fit nonlinear Elovich kinetic model [qt = 1/B ln(A B t +1)] in OriginPro easily! #aminulcheminnovation #AminulSir
https://youtu.be/yF80eY8j-O0
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