Catalysis 2024 Issue

parameters in real-time to maximise yields and energy effi - ciency while meeting emissions standards. Here we give several illustrations: • In addition to gasoline and aromatic production from a reformer unit, the other major product is hydrogen. This hydrogen has a low carbon index compared to the one coming from steam methane reforming (SMR) by a factor of around eight. Therefore, any extra hydrogen production is critical. However, to give advice to increase hydrogen production at a first stage, an accurate estimation of the current hydrogen yield is important. This task is not easy as gas flowmeters are not so accurate most of the time. In that context, Axens has developed special tools to accurately follow hydrogen production using in-house data clustering, mass balance closure methodology, and principal compo- nent analysis. Based on hybrid models, first principles and machine learning, new set points can be defined to maxi - mise hydrogen and aromatics production. • Another example is the optimisation of the recycle gas flow rate. Typically, recycle compressors use steam. Consequently, any reduction of the flow has a direct impact on the unit carbon intensity. Again, based on hybrid mod- els, the recycle gas can be reduced to meet either regenera- tor coke burning capacity or the requested cycle length for a semi-regenerative unit. • Multivariable advanced control embedded to advanced process control uses mathematical models to predict the future behaviour of the process and optimise control actions accordingly. This helps in maintaining optimal con- ditions for catalysts and reactors to achieve higher yields while minimising emissions. • Creating digital twins of refining processes allows for simulation and testing of different scenarios without affecting the actual operation. Applied to the aromatics complex, data densification techniques coupled with real- time monitoring enable an aromatic production increase by maximising benzene precursors in the continuous catalyst reforming (CCR) unit inlet. Operational improvements such as octane optimisation in a catalytic reforming process as a function of pool requirement or hydrogen-to-hydrocarbon molar ratio adjustment minimising energy consumption will favour CO₂ emissions reduction. Q With the most profitable refiners focusing on the pro - duction of basic chemicals such as aromatics, olefins, and polyolefins, what catalyst and reactor technology is key to this focus? A Yoeugourthen Hamlaoui, Global Market Manager, Axens, yoeugourthen.hamlaoui@axens.net Modern refineries are divided between those that empha - sise fuel production, particularly gasoline, and those that prioritise the maximisation of petrochemicals output. Petrochemical-centric refineries seek efficient ways to con - vert gasoline into high-value petrochemical products while minimising investments. In this context, Axens has devel- oped several combinations of technologies to help refiners adapt their existing assets. The combined proprietary technology of Prime-G+ and

GT-BTX PluS unveils an avenue for converting gasoline into valuable petrochemical products. In its petrochemical mode with the same configuration, the GT-BTX PluS Extract, a nearly pure aromatic stream with sulphur being the only impurity, undergoes intensified hydrodesulphurisation (HDS) in the Prime-G+ unit, culminating in a high-quality petrochemical benzene, toluene, xylenes (BTX) product. Furthermore, the olefin-rich non-aromatics raffinate stream derived from GT-BTX PluS proves invaluable for FCC recy- cling, producing significantly additional propylene and enhancing the FCC propylene yield. Axens’ FlexEne technology is a low Capex approach that combines two well-established processes: fluidised catalytic cracking (FCC) and oligomerisation. Polynaphtha (awarded the Best Refining Technology 2023 by Gulf Energy Information Excellence) is the Axens oligomerisation tech - nology dedicated to oligomerise olefins contained in the light cracked cut into higher value olefinic cuts, which can be used as high-octane gasoline or high cold properties kerosene or diesel fraction. This combination aims to enhance the capa- bilities of the FCC process, which is typically the main con- version unit in refineries and is generally oriented towards maximising gasoline and, occasionally, propylene production. The innovation in FlexEne lies in its ability to significantly improve the flexibility of product output, allowing for better control over the balance of propylene, gasoline, and diesel production. This flexibility is achieved by selectively oligom - erising light FCC alkenes (olefins) for recycle cracking in the FCC unit. By adjusting catalyst formulations and operating conditions, the FCC process can be adapted to operate in different modes, including the maximisation of propylene. Prime-G+, GT-BTX PluS, GT-BTX PluS Extract, FlexEne, and Polynaphtha are marks of Axens. A Mark Schmalfeld, Global Marketing Manager, BASF Refining Catalysts, mark.schmalfeld@basf.com Over the coming decades, global market demand for refined products is expected to shift. Fewer transportation fuels will be needed (primarily gasoline as the market shifts to electric vehicles) while we see an increased demand for naphtha, olefins, and other petrochemical feedstocks. Also, besides the global trends, each refiner’s profitability can depend heavily on the regional economics, regional product demand, and integration setup to enable the use of petro- chemical feedstocks (internal to the refinery or to supply to local customers). No specific catalyst or reactor technology in the market has emerged as the only option, but there are market- leading processes in use today. Steam cracking is still one of the largest unit operations to produce ethylene and pro- pylene from naphtha. The FCC unit is generally considered the second-largest unit operation to produce propylene. Additionally, we see many processes supporting the market need with a variety of private licensors and governmental licensor designs introduced. These licensor designs include improvements to the FCC unit, modifications to the FCC unit approach (deep catalytic cracking [DCC], HS-FCC, res- idue fluid catalytic cracking unit [RFCC], INDMAX) to shift

Catalysis 2024