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Alkylation: a Key to Cleaner Fuels and Better Vehicle Mileage

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Alkylation: a Key to Cleaner Fuels and Better Vehicle Mileage Alkylation A Key to Cleaner Gasoline & Better Vehicle Mileage American Fuel & Petrochemical Manufacturers (AFPM) is the leading trade association representing the majority of U.S. refining and petrochemical manufacturing capacity. Our members produce the fuels that power the U.S. economy and the chemical building blocks integral to millions of products that make modern life possible. U.S. gasoline needs alkylate for (OSHA) Process Safety Management and projects to transition from HF to Refineries that are close to chemical facil- its octane and environmental program and the Environmental even newer alkylation technologies are ities may have the option of selling their properties Protection Agency’s (EPA) Risk still in early phases. Eliminating the use propylene and butylene as feedstocks America’s fuel refiners use a chemical Management Program. But refineries that of either HF or sulfuric acid technology to manufacture plastics and sanitizers. process called alkylation to produce use HF go even further. Because nothing would severely diminish U.S. capacity to For refineries without this option, HF Refinery alkylation alkylate, a component of the cleaner is more important to the refining industry manufacture cleaner gasoline in line with alkylation technology provides an answer Alkylation is a refinery gasoline required by today’s higher- than the safety of our people and consumer demand. where sulfuric acid technology does not. is subject to layers process essential to the efficiency automobiles. Nearly 90 U.S. communities, facilities with HF alkylation HF units can co-process both propylene of regulation and refineries — representing 90% of total U.S. units also adhere to exacting industry and butylene to make alkylate. production of cleaner fuels policies — that go above and beyond The myth of interchangeable accountability, including refining capacity — have alkylation units. alkylation technology Alkylation optionality that satisfy the world’s what is required by law — to manage risk strict oversight from: Alongside varying combinations of and keep refining employees, contractors Multiple factors dictate which alkylation Research into alternative alkylation toughest air quality, ethanol, reformate and other products, and neighbors safe. technology a refinery will use, including technologies is ongoing, but HF and sulfuric alkylate increases the octane rating of feedstocks, space constraints, trans- acid are still the only commer cially proven carbon emissions and gasoline which works to reduce premature portation logistics and refinery location. catalysts available to refiners today. auto efficiency standards. combustion and “engine knock” that can The selection of an alkylation catalyst Part of the reason for this is the refining Industry and auditors, damage a vehicle and downgrade engine Once an alkylation unit has impacts configuration of the entire industry’s exacting commitment to per comprehensive Fuel alkylation is part of refinery operation and its other process efficiency. In optimized engines, higher- been designed and built safety and reliability. Engineers and the American success octane gasoline supports better vehicle units. Once a technology is chosen and scientific researchers follow a multi-year, API RP-751 policies story of doubling fuel performance and fuel economy, and lower to use a specific catalyst, the alkylation unit is designed and built to multi-step process to test new fuel overall greenhouse gas emissions. Beyond it cannot be switched use a specific catalyst, refineries cannot alkylation technologies, which includes: OSHA economy, reducing vehicle contributing octane, alkylate also brings flip a switch and swap to the other. HF and sulfuric acid technologies are not · Bench-scale testing to demonstrate carbon emissions by half to the table other unique environmental to operate on the other feasibility of chemistry EPA attributes that help vehicles run cleaner, without major equipment interchangeable. and cutting national air namely low measures of fuel volatility and · Pilot plant testing to verify process viability evaporative emissions —represented by modifications that would pollutant emissions nearly · Demonstration unit testing to determine Department of 80% since the 1970s. low Reid Vapor Pressure (RVP) —that are be infeasible for most scalability and evaluate process, Homeland Security essential in parts of the country where components and material compatibility smog is a concern. Additionally, because facilities to execute. The alkylate has no aromatic content and low two catalyst technologies · Commercial unit testing to confirm Department of sulfur, it helps lower vehicle emissions scalability and ongoing reliability and tailpipe pollution. are not interchangeable Defense and require completely · At least one or two turnaround cycles IHS Markit trends suggest global demand Square footage and feedstock volume (three – five years each) to evaluate safety for alkylate will rise nearly 10% by 2030 different reactor systems. Chemical Safety Sulfuric units require more energy and and reliability over time, and to monitor as more countries motorize. Investments space than HF units. Sulfuric alkylation equipment and unit components for the Board to expand alkylate production capacity requires more acid catalyst, which means effects of corrosion and other potential wear worldwide will be needed to supply this While HF alkylation and sulfuric acid there must be additional feedstock larger market. Both solid acid catalyst (e.g., AlkyClean, State and local alkylation both accomplish the same deliveries and a larger overall reactor. thing — producing alkylate for the Additionally, sulfuric acid units require K-SAAT) and ionic liquid alkylation technol- authorities manufacture of high-octane, low RVP a refrigeration system and access to ogies (e.g., ISOALKY, Ionikylation) are being Two alkylation technologies explored and show considerable promise. support cleaner fuel gasoline and aviation fuel — there are acid regeneration units, either onsite or significant differences in their processing nearby. These are not considerations for As of January 2021, ISOALKY is the only The alkylation process requires a catalyst other technology in operation in the to enable a chemical reaction that safely configurations, equipment and risk facilities with HF units. United States apart from HF and sulfuric converts feedstocks into alkylate. Sulfuric mitigation strategies, though neither Location and waste reduction acid. More time and testing are needed to acid and hydrofluoric acid (HF) are the technology is inherently safer. Alkylation technology is often a reflection ensure these newer technologies can safely two commercially proven alkylation of other feedstocks produces onsite. That and efficiently produce the compo nents catalysts used today, each accounting for Decommissioning one type of alkylation means other refinery processes and of cleaner gasoline in a range of differently about half of U.S. alkylate production. unit to rebuild around the other technology would be a massive under- proximity to petrochemical plants factor into sized and configured refineries. Both catalysts are used safely by fuel taking for a facility, and many would find the decision around alkylation catalysts. Recent progress suggests that new unit refineries around the country and in a wide it impossible given other considerations Refineries do not waste product, and builds and conversions may become range of other industrial settings. They at their sites. In fact, there is no proven complex refineries with fluid catalytic economically feasible. But we still have a are thoroughly regulated by state and commercial pathway for refineries to cracking units (FCC units) need to have a lot to learn. We don’t yet know what total federal workplace and community safety switch from one alkylation catalyst to the system in place to utilize their propylene costs are associated with the adoption of programs, including the Occupational other. No refinery has ever converted an and butylene byproducts. newer catalysts or the reliability of these Safety and Health Administration’s HF unit over to sulfuric acid alkylation, technologies over time. Other refinery processes Butane Isomerization support alkylation & the Butane isomerization converts butane production of cleaner fuels produced by refineries, including FCC America is home to some of the most units, to isobutane. While butane is also sophisticated and advanced refineries a source of octane, it needs to be limited in the world. Our complex refineries in finished gasoline to keep evaporative feature several interconnected processes emissions low, per the Clean Air Act’s that each play a part in turning crude Reid Vapor Pressure (RVP) rules. Converting oil — even the toughest-to-refine heavy excess butane into isobutane through sour types — into fuels clean enough isomerization creates a valuable for today’s high-performance engines feedstock for refinery alkylation units. and stringent U.S. air quality and auto Catalytic Reformer emissions standards. Alkylation and isomerization units aren’t Alkylation units allow refineries to upgrade the only sources of fuel octane at refin- lower value feedstocks into high value eries. Catalytic reformers produce octane alkylate. Other refinery units produce too — converting low-octane naphtha the feedstocks required for alkylation, so (produced during crude distillation) into wherever fuel alkylation units are located high-octane reformate to
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