Material balance for a reactive systems are based on the limiting reactant of the process. It is defined as the reactant that gets consumed first during the process. For a reactor, material balance can be done as follows :
2. Coefficients of the species in the reaction equation indicate the ratio or proportion of reactants required in exact quantities during a reaction. In the reaction,
HCl + NaOH –> NaCl + H2O,
1 mole of HCl reacts with 1 mole of NaOH to give NaCl and 1 mole of water. It indicates that per one mole of HCl , 1 mole of NaOH will be consumed and vice versa.
3. If the number of moles of reactants fed are not same in proportion as in reaction, find the species that is present in lower quantity than required. This is the limiting nutrient and also the basis of calculation.
4. Divide the limiting reactant with its coefficient. Find the quantities of other reactants consumed by multiplying this with their coefficient. Similarly calculate the amount of products.
We have created an interactive sheet to solve material balance for reactive systems which can be accessed here. It can perform material balance for both continuous and batch reactions. It can be used to calculate conversion and to find limiting reactant.