Global  SAF production doubled in 2023, reaching over 600 million liters (approx. 158.5 million gallons), according to the International Air Transport Association. Remarkably, production is expected to triple in 2024, reaching 1.875 billion liters. With an all-hands-on-deck approach needed in this massive effort to decarbonize the global aviation sector, technology developers like Honeywell are key in driving this surge in production forward. Recently, SAF Magazine spoke with major player Honeywell's Barry Glickman, vice president and general manager of sustainable technology solutions, about the company’s technology and efforts in the industry.

In January 2024, Honeywell reorganized its businesses into different branches themed around automation, the future of aviation and energy transition. These four businesses are Aerospace Technologies, Industrial Automation, Building Automation and Energy and Sustainability Solutions. Glickman begins by discussing Honeywell’s Ecofining technology and the importance of technology providers in finding sustainable solutions. Honeywell’s Ecofining technology turns nonhydrocarbon fats, oils and greases into biodiesel or sustainable aviation fuel. The process takes the feedstock through a pretreatment phase, a hydroprocessing phase, and a fractionation phase. Ecofining uses the hydroprocessed esters and fatty acids (HEFA) process, which is widely recognized by the industry as a “capacity constrained” solution to decarbonizing aviation and other industries due to the disparity between feedstock availability and the volume of SAF and renewable diesel needed worldwide.

Recognizing this issue, Honeywell developed a program to enable the use of additional feedstocks. Two such technologies are Honeywell’s ethanol-to-jet fuel technology, known as ethanol-to-jet (ETJ), as well as a CO2-to-SAF process, entitled eFining. Glickman explains that Honeywell finds that one technology is missing, namely a process that turns biomass into syncrude, and then turns that syncrude into SAF. This technology is “actively developing” at Honeywell, says Glickman.

Enabling the Energy Transition 
As nations and corporations worldwide announce net-zero emissions goals, technology providers have a unique and challenging role to play in making those goals a reality. “Technology providers are essential, or we’re not going to get there,” Glickman says. “And I say that not just because I’m a technology provider, but as a consumer of various products. We as consumers generally are not interested in or willing to make dramatic changes in our behavior.”

It is critical that countries’ electrical grids are reliable and that transportation’s safety and reliability is not sacrificed for the sake of the energy transition, Glickman explains. “There’s a possibility we will displace very short haul with some other form of transportation or with some other form of fuel,” he says. “But for long-haul aviation, the demand is going to increase—we’re not willing to change; therefore, we need technology companies to provide solutions that we need and governments to provide the market frameworks to enable the solutions.”

The world’s population is growing, and along with it, air travel is likely to grow. To develop the technologies needed to move the SAF industry forward, innovators need regulation clarity from governments. Glickman divulges Honeywell’s two “asks” for regulators around the world when having conversations about the energy transition. “The first is, there must be an explicit price of carbon,” he says. “Honeywell is generally indifferent on the market mechanism, but there has to be a way to notify the marketplace that CO2 has a cost. If you don’t do that, then it’s very difficult to drive energy transition. But the second feature that we ask [for] when we meet with regulators is that there [be] a way to provide the fiscal infrastructure for things like CO2 transportation and sequestration, the movement of hydrogen, and the movement of SAF within existing fiscal infrastructures.”

There are different approaches across the world to addressing technology developers' needs, Glickman explains. For example, the United States uses a benefits structure to encourage CO2 reduction, whereas EU member states use a combination of requirements for the total volume of renewable fuels used along with an explicit tax on CO2 emissions. "Many countries fit into one of these two groups; however, the third group of countries are those that have some form of a renewable fuel goal in place without any mandate, subsidy or tax structure to support it," he says. "If you map all the countries of the world, generally [each country] will fit into one of those three categories,” he says. “The third category is the hardest to get traction with.”

Process Specifics 
SAF has the advantage of being a drop-in fuel when blended with 50% Jet A, meaning that both fuels are chemically identical to their fossil fuel counterparts. “Airlines are getting a mix of SAF and Jet A that doesn’t require them to change anything in their infrastructure,” Glickman says. “That’s the beauty of our products.”

The second advantage is that the refining technology and infrastructure for the finished products already exists. The challenges for renewable diesel and SAF made with Ecofining technology are rooted in regulations and feedstock supply rather than the production process.

Ecofining begins with a waste or renewable feedstock such as used cooking oil (UCO), which fits into the fats, oils and greases category of feedstocks. There are two different types of Ecofining processes, a single-stage process for renewable diesel and a two-stage process for making SAF. In both processes, the UCO is sent through a pretreatment process to remove contaminants that would foul up the downstream process. “Step one is [the result of] an industry out there that is collecting and aggregating the feedstocks. The operators contract with the feedstock suppliers, the feedstock generally arrives at the site and then goes through an onsite pretreatment process to be part of the Ecofining process,” Glickman explains.

The UCO then goes through a deoxygenation and isomerization process that removes oxygen and adds hydrogen to the feedstock. The single-stage process does both deoxygenation and isomerization in the same reactor, while the two-stage process does deoxygenation in one step, then hydrocracking and isomerization. Following these steps, the feedstock is ready to be distilled or fractionated into components such as SAF, renewable diesel, naphtha or renewable gasoline. “The novel piece is really the feedstock they’re using, the pretreatment and the hydrotreating or hydroprocessing stage of the process that Honeywell UOP has been doing a long time and has the process experience and the feedstock specific catalysts, which enable the first stages of the refining process for these novel feedstocks in a way that minimizes the capital costs—the operating costs of the conversion,” he says. The process is compatible with both greenfield projects and oil refinery retrofits.

Currently, Honeywell has more than 50 licensees for their renewable fuels technologies, which include Ecofining, ETJ, and UOP eFining. In these relationships, Honeywell provides a range of technology, including license and engineering, catalysts, digital services and equipment. Glickman explains that the process is often incorporated into an existing refining footprint. Honeywell also works closely with the operators when they purchase the engineering. “There are numerous plants that are already producing renewable diesel and SAF, there are eight plants in operation at commercial scale, and there are dozens more in the process of coming online,” he says.

Hydrogen Production 
The hydrogen used in the Ecofining process will be one of three “colors”: gray, blue or green, which indicate the process by which it was made. Traditionally, refiners made gray hydrogen by changing natural gas into syngas using a steam methane reformer or an auto thermal reformer. The hydrogen is then pulled out of the syngas. Blue hydrogen uses the same process as gray hydrogen but captures the carbon dioxide and sequesters it. Honeywell makes the carbon capture technology needed to turn gray hydrogen into blue hydrogen, integrates it into the refinery, and provides the equipment, system and services. The carbon capture and storage (CCS) system enables the operator to capture the CO2 out of the hydrogen or syngas process so that it can be transported or sequestered. CCS significantly decarbonizes the Ecofining process and the final product. “From a global decarbonization standpoint, capturing CO2 from the production of hydrogen may be one of the most impactful near-term activities the world can do to decarbonize,” Glickman says. “We have a project with Exxon Mobil at its Baytown refinery that will enable Exxon to capture over seven million tons of CO2 per year.”

The process of making green hydrogen is entirely different from gray and blue hydrogen. “If you want to do green hydrogen, you’re not dealing with [autothermal reforming] or [steam methane reforming]. If you are making green hydrogen, you are dealing with an electrolyzer, which is the device that takes renewable power and uses it simply to crack water, Glickman says. "What you get is water and electrical currents intaking oxygen and [putting] hydrogen out. Honeywell doesn’t provide electrolyzers; we provide the intel inside portion of the electrolyzer, which is the catalyst-coated membrane.”

Found inside the stack of the electrolyzer, the CCM Honeywell manufactures reduces the cost of the green hydrogen produced and leverages the company’s expertise in membranes and catalysis, Glickman explains.

As demand for renewable diesel, SAF and related fuels and chemicals soars, Ecofining and the supporting technologies of CCS and hydrogen provide fuel producers with options to accelerate decarbonization with fully commercialized technology. “Honeywell renewable fuels are not R&D—these are commercially available, commercial-scale technologies in places with multiple operators around the world,” Glickman adds. "They're very well-demonstrated and proven technologies."

Author: Katie Schroeder 
Staff Writer, SAF Magazine 
katie.schroeder@bbiinternational.com