Theoretical analysis and evaluation of reaction routes by “three-parameter difference”

Abstract

“Three-parameter difference” analysis of the reaction route for the synthesis of toluene diisocyanate from toluene as raw material.

Exploring Greener Pathways and Catalytic Systems for Ethylene Carbonate Production

“…The three-parameter difference method defines the difference R i between the three parameters x Δ G i ° , y au i , and Z ISI i of the chemical reaction i and the three parameters (−1, 1, 0) of the ideal chemical reaction. For an ideal chemical reaction, the value of Δ R i is zero, so the best synthesis route in terms of thermodynamic feasibility, greenness, and safety will be the one having the lowest value of Δ R i , as given by eq Δ R i = [ ( x Δ G i ° + 1 ) 2 + ( y a u i − 1 ) 2 + ( z I S I i ) 2 ] 0.5 goodbreak0em1em⁣ i = 1, 2, 3 where x Δ G i ° is the ratio of the Gibbs free energy of reaction i to the absolute value of the minimum Gibbs free energy for all reactions, the atom efficiency y au i is the ratio between the total mass of desired product atoms and the total mass of reactant atoms in reaction i , and Z ISI i is the ratio of the inherent safety index of reaction i to the maximum inherent safety index of all reactions . Scores for calculating the subindices involved in the calculation of the inherent safety index, ISI, are taken from Heikkilä’s ISI, while those for the process yield index are from Edwards and Lawrence’s PIIS …”

“…The "three-parameter difference" method recently introduced by Song et al 84 provides a rational basis for the quantitative assessment of the three different synthesis routes. This method utilizes the Gibbs free energy, atom efficiency, and inherent safety index as a basis for evaluating the overall thermodynamic feasibility, greenness, and safety of the chemical reactions.…”

“…where x ΔGd i °is the ratio of the Gibbs free energy of reaction i to the absolute value of the minimum Gibbs free energy for all reactions, the atom efficiency y aud i is the ratio between the total mass of desired product atoms and the total mass of reactant atoms in reaction i, and Z ISId i is the ratio of the inherent safety index of reaction i to the maximum inherent safety index of all reactions. 84 Scores for calculating the subindices involved in the calculation of the inherent safety index, ISI, are taken from Heikkila's ISI, 85 while those for the process yield index are from Edwards and Lawrence's PIIS. 86 Table 5 presents a summary of the process conditions reported for each synthesis route (from Tables 2−4), plus the key parameters involved in the three-parameter difference method.…”