Enhanced olefin production via a novel radial-flow membrane reactor of heavy paraffin dehydrogenation in LAB plant

• Mathematical modeling of paraffin dehydrogenation in a novel radial-flow membrane reactor.
• Multi-objective optimization of radial-flow membrane reactor using NSGA-II method.
• Maximization of olefin production and selectivity as objective functions.
• Pareto optimal solutions with optimum values of both objective functions.
• Highest olefin productivity and selectivity under optimal conditions.

In the present study, a membrane reactor with radial-flow pattern of the sweeping gas and the paraffin feed named as radial-flow membrane reactor (RF-MR) is proposed for heavy paraffin dehydrogenation. In this novel configuration, the cross section area of the industrial radial-flow tubular reactor (RF-TR) is divided into some subsections. The walls of the gaps are coated by a Pd–Ag membrane layer to separate hydrogen from the reaction side and enhance the olefin production. The performance of RF-MR is investigated and subsequently compared with the RF-TR. The simulation results show 26 and 5.38% enhancement in the olefin production and selectivity of RF-MR compared with radial-flow tubular reactor (RF-TR). Moreover, the operating conditions of RF-MR are optimized via Non-dominated Sorting Genetic Algorithm-II (NSGA-II). The optimization problem involves two objective functions, namely, maximization of olefin production rate and selectivity. Optimization results give the optimum values of operating conditions, under which the highest olefin production rate and selectivity can be achieved.