Abdullah Liaqat, Indeed, the mass and energy balance equations are identical for the processes running in both types of reactors, but only in a mathematical sense. The difference is in the independent variables. In a batch operating reactor, the independent variable is the calendar time, and in a tubular reactor, the independent variable is the current volume of the reaction space or the current length. For the assumed conversion degree and production capacity, the volume of the reaction space in the CSTR is greater than for the tubular and batch reactor. The exception is the autocatalytic reaction. However, it is not always justified to use a tubular type reactor. Sometimes a cascade of CSTRs may be an alternative.

The character of the equation remains the same except that the slope and intercept of the straight lines are changed, Plug flow reactor and mixed flow reactor having a main difference between them is in PFR.The concentration and the rate of reaction inside the reactor is different at each and every point of reactor but MFR it is same at each & every point insider. Batch reactor is an unsteady-state operation. at any instant the composition throughout the reactor is uniform. plug flow reactor, lateral mixing of fluid in a PFR occurs. Mixed FR, in which the contents are well stirred and uniform throughout

https://www.slideshare.net/PremBaboo/chemical-reaction-engineering-51679846

Abdullah Liaqat, The topic is very broad, and it cannot be fully answered in one short post. The above comparison of the three types of reactors in terms of their production capacity referred, firstly, to the so-called ideal reactors and, secondly, to single reactions taking place under isothermal conditions. If we were to consider other thermal conditions or instead of a single reaction we took into account the reaction system, e.g. two parallel or consecutive reactions, the comparison would be neither simple nor unambiguous. It is also worth remembering that when assessing the production capacity of a reactor operating in a batch regime, auxiliary operations, such as cleaning the inside of the reactor, should be taken into account.

Thanks all for your detailed answers!

Agree with all thses colleagues, but adding one thing: only true for isothermal conditions. Easy to handle in PFR (due to relatively high S/V ratio and significant heat transfer); more critical in batch mode (for the opposite reasons).