Steam cracking is highly endothermic and requires significant external heat input. Gaseous light olefins are formed via reactions involving free radicals. At elevated temperatures in the radiant section of the furnace (750–900 ℃ or higher), naphtha is cracked into smaller molecules in the absence of catalysts. In naphtha-based steam-cracking processes, naphtha is first fed into the convective section of the furnace for preheating and vaporization. Naphtha is a mixture of hydrocarbons with a boiling point range of 30–200 ℃. Although ethane is the most common feedstock for cracking in the United States and Middle East, more than 80% of the ethylene produced in Europe and the Asian-Pacific region is from naphtha. Due to its high endothermicity and complex product-separation steps, steam cracking is one of the most energy-intensive processes in the chemical industry. ![]() At present, ethylene is almost exclusively produced via the steam cracking of gaseous and liquid hydrocarbon feedstocks such as ethane, naphtha, and gas oil. Global ethylene production capacity was around 1.48×10 8 t in 2014, representing a 32% increase over the past decade. The upstream section of the process consumes approximately 67% less energy while producing 28% more ethylene and propylene for every kilogram of naphtha feedstock.Įthylene is one of the most important organic materials it is used as a building block to produce fibers, plastics, and other chemicals. Compared with traditional naphtha cracking, the ROC process can provide up to 52% reduction in energy consumption and CO 2 emissions. In this study, the ROC process is simulated with ASPEN Plus® based on experimental data from recently developed redox catalysts. Moreover, the formation of ethylene and propylene can be enhanced due to the selective combustion of H 2. ![]() This intensified process reduces parasitic energy consumption and CO 2 and NO x emissions. The redox catalyst is subsequently re-oxidized by air and releases heat, which is used to satisfy the heat requirement for the cracking reactions. ![]() In this two-step process, hydrogen (H 2) from naphtha cracking is selectively combusted by a redox catalyst with its lattice oxygen first. We propose an alternative process for the redox oxy-cracking (ROC) of naphtha. Ethylene production by the thermal cracking of naphtha is an energy-intensive process (up to 40 GJ heat per tonne ethylene), leading to significant formation of coke and nitrogen oxide (NO x), along with 1.8–2 kg of carbon dioxide (CO 2) emission per kilogram of ethylene produced.
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