Integrated Process Design–Computational Chemistry Framework for Process Intensification: H2S Recovery and Conversion

Phase transfer catalysis (PTC) is a general methodology with importance in intensified extraction-reaction processes, and it is applicable to a large number of chemical reactions. This technique accommodates reactions that are generally not achievable through conventional synthesis methods due to the introduction of a homogeneous catalyst for biphasic systems that can transfer a reactant species between two immiscible phases. This two-phase system offers several advantages, such as high conversion yields, high purity of products, operational simplicity, mild reacting conditions, suitability for scale-up of the process, and an environmentally benign reaction system. The economic viability and successful implementation of the large-scale process are heavily contingent on the design and modeling of these kinds of systems.
Although a number of attempts have been made to develop case-specific and generalized models for PTC, the proposed models and accurate thermodynamic parameters are not fully developed. The lack of published theoretical process modeling for scale-up hurts the commercialization potential of PTC. In this study, an integrated and multi-scale modeling framework is proposed for overcoming these limitations for liquid-liquid (LL)-PTC. The framework needs little to no experimental data and combines different tools at different time and space scales to model virtually any LL-PTC system. The goal of this work is to utilize this framework for the recovery and conversion of H2S from an aqueous alkanolamine solution into value-added products as a way to improve economics and sustainability of the process, specifically at offshore oil and gas platforms.