Integrated membrane operations in the ethylene oxide production

Abstract

Petrochemical industry, highly energy and capital intensive, might significantly benefit from the implementation of membrane operations for meeting stringent environmental standards, controlling production cost and final product's quality. Membrane units have been proved effective for improving the efficiency of different industrial productions. Ethylene oxide (EO), an important petrochemical intermediate, is produced by selective catalytic oxidation of ethylene, a valuable hydrocarbon feedstock. In this study, the EO manufacturing cycle is redesigned by integrating different membrane operations. Both the conversion and separation sections of the plant are investigated, considering the use of membrane reactors (MRs) for the separate feeding of the oxidant, membrane contactors (MCs) for the absorption of EO and carbon dioxide, and gas separation (GS) membrane units for the hydrocarbon recovery before their being recycled to the reactor. Design considerations are provided, and the benefits coming from each membrane operation, as well as from their synergic integration, are outlined with particular attention to environmental impact, raw materials and energy consumption.

Extremely Low Temperatures for the Synthesis of Ethylene Oxide

“…An alternative process configuration, which is proposed and discussed in this work, can be based on the use of oxygen-enriched air, a low-cost waste stream deriving from the air separation by cryogenic distillation or membrane . This option allows for the reduction of the inert content without detrimental effects from a safety standpoint, thus approaching the performance of the O 2 -based process without the drawback of severe purging and more restricted flammability ranges . Here, it is also worth noting that ethylene is often transported via pipeline.…”

“…2 This option allows for the reduction of the inert content without detrimental effects from a safety standpoint, thus approaching the performance of the O 2 -based process without the drawback of severe purging and more restricted flammability ranges. 9 Here, it is also worth noting that ethylene is often transported via pipeline. However, the robustness and accessibility of cryogenic technologies obtained due to the widespread nature of liquefied natural gas 10 make the use of liquid ethylene (T eb = −103.7 °C) convenient.…”

“…Eventually, the collection of additional data on ethylene/ methane/oxygen/nitrogen flames may be paramount for a fundamental understanding of hydrocarbon chemistry, for safety considerations, and more in general for the improvement of the oxygen-enriched epoxidation process, which may take advantage of the low cost of the oxidant due to membrane development. 9 To this aim, this work presents a preliminary analysis aiming at the comparison of experimental and numerical data related to ethylene-containing flames, followed by an in-depth investigation for the identification of optimized conditions for ethylene oxide production via a process based on the use of oxygen-enriched air. Key performance indicators (KPIs) merging several aspects from safety and kinetic perspectives were defined and assessed to identify the most convenient solutions.…”

Efficient and clean production of fuels and biofuels: a summary

“…An interesting work from Paola Bernardo and Gabriele Clarizia, Istituto di Ricerca per la Tecnologia delle Membrane, ITM in Arcavacata di Rende (CS), Italy brings an attempt at the implementation of membrane operations for meeting environmental standards, controlling production cost and final products quality. The paper Integrated membrane operations in the ethylene oxide production (Bernardo and Clarizia 2012) investigates the conversion and separation sections of the plant, considering the use of membrane reactors for the separate feeding of the oxidant, membrane contactors for the absorption of ethylene oxide and CO 2 and gas separation membrane units for the hydrocarbon recovery before their recycle to the reactor. Design considerations are provided and the benefits from each membrane operation, as well as from their synergic integration, are outlined with particular attention to environmental impact, raw materials and energy consumption.…”

Prospect of Mixed Matrix Membrane towards CO2 Separation

“…In spite of its popularity, the chemical solvent technology has certain limitations such as expensive operational cost, high heat reaction with CO 2 , and corrosive nature of some solvents [2]. In contrast, gas separation using membrane technology provides good benefits such as energy efficiency, utilization of non-toxic chemical, and simple operating procedure that makes it extremely attractive for CO 2 capture [3]. In terms of energy requirements, membrane technology was comparable for the adsorption of flue gases containing 20% or more of CO 2 [4].…”