Oxidative dehydrogenation (ODH) of light alkanes to produce C2-C3 olefins is a promising alternative to conventional steam cracking. Perovskite oxides are emerging as efficient catalysts for this process due to their unique properties such as high oxygen storage capacity (OSC), reversible redox behavior, and tunability. Here, we explore AFeO3 (A=Ba, Sr) bulk perovskites for the ODH of ethane and propane under chemical looping conditions (CL-ODH). The higher OSC and oxygen mobility of SrFeO3 perovskite contributed to its higher activity but lower olefin selectivity than its Ba counterpart. However, SrFeO3 perovskite is superior in terms of cyclic stability over multiple redox cycles. Transformations of the perovskite to reduced phases including brownmillerite A2Fe2O5 were identified by X-ray diffraction (XRD) as a cause of performance degradation, which was fully reversible upon air regeneration. A pre-desorption step was utilized to selectively tune the amount of lattice oxygen as a function of temperature and dwell time to enhance olefin selectivity while suppressing CO2 formation from the deep oxidation of propane. Overall, SrFeO3 exhibits promising potential for the CL-ODH of light alkanes, and optimization through surface and structural modifications may further engineer well-regulated lattice oxygen for maximizing olefin yield.

Ethylene and propylene production from steam cracking in Europe: a consequential perspective

Effect of Reactor Alloy Composition on Coke Formation during Butane and Ethane Steam Cracking

Steam cracking in fluidized beds offers an alternative to conventional steam cracking for sustainable hydrocarbon production. This approach has gained interest, particularly in the context of recycling plastics to generate valuable hydrocarbons. Integrating this process into existing petrochemical clusters necessitates a thorough characterization of the products derived from this new feedstock. This work focuses on addressing the challenges associated with species quantification and characterization time for assessing the product mixture resulting from a steam cracking process. The experiments were conducted in a semi-industrial scale dual fluidized bed steam cracker, utilizing polyethylene as the feedstock. To sample species spanning from C1 to C18, cooling, scrubbing, and adsorption were introduced. These steps were integrated with GC-VUV (Gas Chromatography with Vacuum Ultraviolet Spectroscopy) and other widely recognized analytical methods to quantify the sampled species. The primary focus was on GC-VUV analysis as a suitable characterization method for identifying and quantifying C4 to C18 species, which can constitute up to 35% of the product mixture obtained from polyethylene steam cracking (750 °C to 850 °C). Quantifying C6 to C18 hydrocarbons becomes the time-critical step, with GC-VUV potentially achieving this in 1/6th of the analysis time and with relatively optimal quantification compared to the traditional characterization methods.

Economic and geopolitical trends in global oil markets are unfolding alongside significant structural changes in the fuel and energy industry (FEI). These developments are driving a transition to alternative vehicle fuels due to worsening environmental conditions and promoting the refining of crude oil into petrochemical products. This transformation is critical for meeting domestic demand and complying with increasingly stringent environmental and economic standards in foreign markets. A key objective for the crude refining complex (REF) is now to supply feedstock to the petrochemical sector (PETR). Steam crackers, the cornerstone of the global petrochemical industry, use different feedstocks depending on the region: naphtha in Europe and Asia, gas in North America and the Middle East, and coal in China. (However, in China, the reliance on coal is outdated. Currently, the primary energy source is Nahphtha based). In our country, the steam cracker is designed to process both liquid (naphtha) and gaseous (ethane) feedstock. However, limited crude throughput has created supply challenges for straight-run naphtha, a vital input for fuel production (catalytic reforming) and petrochemical production (steam cracking). Since oil refineries are the primary source of petrochemical feedstock, this article evaluates how intensifying crude refining processes could expand feedstock availability. Seven refining configurations were developed, incorporating new processes (hydrocracking, deasphalting) and modifications to existing processes (catalytic cracking). The analysis shows that deep catalytic cracking and deasphalting could boost feedstock supply to steam crackers by 8-10 %. Case 3 was identified as the most suitable configuration for the short term through comprehensive technical and economic calculations, ensuring optimal efficiency and cost-effectiveness. Keywords: crude refining; petrochemicals; liquified gases; deep catalytic cracking; deasphalting; hydrocracking.

Activated carbon adsorption of heteroatom components from pyrolysis oil for improved chemical recycling

Comprehensive Fouling Assessment in Steam Crackers: Fossil versus Renewable NEXBTL Naphtha

Comparing different methods for olefin quantification in pygas and plastic pyrolysis oils: Gas chromatography-vacuum ultraviolet detection versus comprehensive gas chromatography versus bromine number titration

Annular swirling jet reactor for converting hydrocarbons to olefins and aromatics

Assessment of Kinetic Indicators of Coke Formation in the Course of Steam Cracking with the Use of Inhibitors

Plastics account for 4.5% of global greenhouse gas (GHG) emissions, which are hard-to-abate due to the use of fossil fuels as feedstock. Our study develops a cradle-to-gate life cycle assessment of bioethylene production, exploring 33 pathways across Brazil, the EU, and the US. It aims to understand whether substituting fossil-based ethylene with bioethylene contributes to lowering carbon emissions, and in which of the relevant bioenergy-producing regions/countries the valorisation of biofuels as feedstocks would provide a less carbon-intensive bioethylene production. Results indicate that bioethylene production through catalytic dehydration of sugarcane bioethanol in Brazil presents lowest GHG emission. This pathway could deliver up to −2.1 kg CO2e/kg ethylene when accounting for biogenic carbon storage in long-lived applications such as infrastructure. In contrast, beef tallow performs the poorest as a raw material, regardless of whether land-use change (LUC) emissions are considered. When biogenic carbon storage is factored out, none of the pathways outperforms conventional fossil-based steam cracking; however, some are within the fossil-based range indicating potential indirect benefits through reduced refinery utilisation. Our study underscores that biomaterials production as a climate mitigation strategy must be on par with circular economy measures and the conservation of native forestry ecosystems. These results are particularly relevant to policymakers and industries seeking to align polymer manufacturing with sustainability objectives.

The propylene production processes currently used in the petrochemical industry (fluid catalytic cracking and steam cracking of naphtha and light diesel) are unable to meet the increase of propylene demand for industrial applications. For this reason, alternative processes for propylene production have been investigated, and among the others, the propane dehydrogenation (PDH) process, allowing the production of propylene as a main product, has been industrially implemented (e.g., Catofin and Oleflex processes). The main drawback of such processes is closely linked to the high temperature required to reach a sustainable propane conversion that affects catalyst stability due to coke formation on the catalyst surface. Accordingly, the periodic regeneration of the catalytic bed is required. In this work, the performance in the PDH reaction of different Sn-Pt catalysts, prepared starting by alumina- and hydrotalcite-based supports, is investigated in terms of propane conversion and selectivity to propylene in order to identify a more stable catalyst than the commercial ones. The experimental tests evidenced that the best performance was obtained using the catalyst prepared on commercial pellets of hydrotalcite PURALOX MG70. This catalyst has shown, under pressure conditions of 1 and 5 bar (in order to evaluate the potential future application in integrated membrane reactors), propane conversion values close to the thermodynamic equilibrium ones in all of the investigated temperature ranges (500-600 °C) and the selectivity was always higher than 95%. So, this catalyst was also tested in a stability run, performed at 500 °C and 5 bar: the results highlighted the loss of only 12% in the propane conversion with no changes in the selectivity to propylene. Properly designed experimental tests have also been performed in order to evaluate the kinetic parameters, and the developed mathematical model has been optimized to effectively describe the system behavior and the catalyst deactivation.

Electrification of steam cracking as a pathway to reduce the impact of the petrochemical industry on climate change

On the mechanism of initiation steam cracking of C6 hydrocarbons by hyperbranched poly(amidoamine) (PAMAM) initiator

This paper describes the simulation and techno-economic evaluation of a carbon dioxide capture and utilization unit integrated in a cement plant with a capacity of 10,000 tons of CO2 per year. The aim is to utilize CO2 along with hydrogen to produce lower olefins (C2–C4), the feedstock for polyolefin production. In a first step, three process routes, namely a Fischer–Tropsch synthesis with steam cracker, a methanol synthesis with rWGS syngas production and a methanol synthesis with direct hydrogenation of CO2, latter two followed by a methanol-to-propylene unit, are simulated in ASPEN Plus V12.1®. Furthermore, the effect of a high- and a low-temperature electrolysis on key performance indicators are also considered in the evaluation. Additionally, an estimation of investment, operating and specific net production costs (NPCPR) of the different process routes is made. The evaluation is based on the comparison of calculated global efficiencies, specific energy consumption (SEC), NPCPr and yields of the lower olefine products (C2–C4). The power-to-lower olefin plant, consisting of an amine scrubber unit, a PEM electrolysis and a Fischer–Tropsch synthesis with downstream steam cracker proves to be the most efficient process route for polyolefin production, resulting in a global efficiency of 38.2 %, an SEC of 34.4 kWh/kg and an NPCPr of 14.92 EUR/kg of lower olefine product.

Life-cycle analysis of recycling of post-use plastic to plastic via pyrolysis

The main objective of the Steam Cracker is to produce monomers prone to polymerization. The drawback is that polymerization can occur in the Steam Cracker itself. The main monomers fouling precursor is Butadiene. All along the separation process, Butadiene concentration and process temperature change. This implies step changes in polymer structure and fouling level. Several techniques are used to control this fouling, including oxygen ingress control, the use of additives such as antioxidants and free radical scavengers. By a catalytic effect, the metal surfaces can also be a polymerization initiator. The objective of passivation is to modify the Carbon Steel surface into stable magnetite and maghemite. Using electrochemistry to characterize different Carbon Steel samples, we were able to improve our passivation procedure. And when applying metal passivation, we were able to increase run length of Depropanizer reboilers limiting the fouling rate and its impact on operation.

C2H4 is a key building block in the chemical industry to produce a wide range of plastics, solvents, cosmetics, etc. On average, the production of 1 MMT of C2H4 generates 1.5 MMT of CO2, coming from fuel combustion, decoking, and utilities. Globally, C2H4 production by steam cracking is ranked as the second-largest contributor of energy consumption (2.8 EJ/year) and greenhouse gas emissions (300 MMT of CO2-e/year) in the chemical industry. Electrochemical CO2 reduction reaction (CO2RR) to produce C2H4 at ambient conditions, when coupled with renewable electricity, could reduce dependence on fossil fuels and decarbonize the chemical sector associated with C2H4 production. However, more efforts are needed to improve selectivity, productivity, and durability before the CO2 electrolyzer can be deployed commercially.State-of-the-art continuous CO2 electrolyzers utilize gas diffusion electrodes (GDEs) to achieve CO2-to-C2H4 conversion at industrially relevant current density. However, managing the flooding of liquid electrolytes into the porous structure of GDE remains a critical practical challenge for stable and efficient CO2 transport. To date, most CO2 electrolyzers used commercial gas diffusion layer (GDLs) designed for polymer electrolyte membrane fuel cells (PEMFC), which operate under different conditions than CO2RR. The conventional GDL is generally made of carbon paper coated with 5-30 wt.% of polytetrafluoroethylene (PTFE) to protect against flooding. These GDLs still lose hydrophobicity fast during CO2 electrolysis at highly negative potentials due to the electrowetting of carbon materials, salt precipitation, and chemical degradation. As a result, the electrolyte even penetrates the micropores of the GDL, blocking CO2 transport to catalyst sites.Giner has designed an innovative structure, the water management GDL (WM-GDL), providing a breakthrough solution for water management under the operational conditions of a CO2 electrolyzer. The WM-GDL has dedicated mass transport pathways for gas and electrolyte, which allows durable and efficient mass transport of both over long-term operation. The utilization of WM-GDL will assist in the scale-up of electrochemical CO2-to-C2H4 conversion. Currently, the state-of-the-art WM-GDL achieved 60% C2H4 selectivity at 500 mA cm-2 and 3 V in a 50 cm2 MEA electrolyzer. Larger-scale demonstration of the CO2-to-C2H4 conversion with high selectivity and durability will be carried out in stacks. Acknowledgment: The project is financially supported by the Department of Energy’s Office of EERE under the Grant DE-EE000942l

With the shift away from fossil resources, there is a need for alternative pathways to carbon-based commodities such as ethylene. The electrochemical oxidative coupling of methane (OCM) enables the synthesis of higher hydrocarbons from simple organic molecules i.e., methane and has the potential to replace conventional ethylene production in the future. However, current solid oxide OCM cell development is still in an early stage and more comprehensive system-level analyses are needed to better understand operating conditions and economics to guide research and development. For this purpose, process models and new integration strategies for the electrochemical OCM process were developed. The integration of the electrochemical OCM unit into the plant revealed to be challenging based on current solid oxide cell designs and will be discussed as part of this presentation. The performance of the OCM plant is benchmarked against current state-of-the-art ethane steam cracker plants. In this context, key performance metrics are efficiency, direct and indirect carbon dioxide emissions, power consumption, plant cost and cost of ethylene. Of particular interest are aspects of hydrogen co-production and carbon dioxide utilization as well as the impact of carbon dioxide emission factors from the grid, which have shown to be of particular importance for electrochemical processes. Moreover, critical aspects of heat integration will be discussed including fuel pre-heating, carbon deposition and thermal cell management. The analysis will provide new insights into economic cost driving factors and the impact of cell cost, current density, overpotentials and Faraday efficiency upon the cost of ethylene. Based upon this information, performance targets will be recommended that will allow electrochemical OCM to become economically competitive in a free market environment.

Feedstock recycling of cable plastic residue via steam cracking on an industrial-scale fluidized bed