A single-step protocol for closing experimental atom balances

Abstract

Molar balances are considered to be closed if they are within 95–105%. It was shown in the companion paper “https://doi.org/10.1016/j.cej.2018.12.113; Chem. Eng. J., 361, 805–811 (2019)” that even this condition can give rise to pronounced deviations in conversion or selectivity data (Heynderickx, 2019). This manuscript offers a very simple a posteriori calculation procedure to address these deviations via simple linear algebra. The specific details of this procedure, called ‘CLOBAL’, after ‘closing the balances’, are shared (1) by showing the mathematics behind-the-scene and (2) by showing the specific programming code with an itemized guideline through the code.Key benefits of proposed procedure CLOBAL script are: • Physical quantities such as molar flow rates, concentrations or absolute number of moles are updated via a one-step linear procedure to close the corresponding atom balances; • The presented CLOBAL procedure, is executed in Excel®, which is accessible and practical for every user – no need for special license and the code is provided; and • Parameter estimation, using treated data, results in smaller confidence intervals and lower residual sum of squares (RSSQ).

Keywords

• Closing atom balances
• Accuracy
• Excel® data sheet