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Selective Extraction of Asphaltenes

About SELEX-Asp

Selective Extraction of Asphaltenes ("SELEX-Asp") is a patented and commercially proven decarbonization technology backed by over 40 years of research and development. The process is used to upgrade oil by removing solid carbon (asphaltenes) from petroleum feedstocks.

Inspired by the decaffeination process, SELEX-Asp is a solvent-based physical separation process that operates under the principles of supercritical fluid extraction and fractionation. The technology is low complexity, energy efficient, and cost effective.

To date, there exists 36,500 bpd of installed SELEX-Asp processing capacity across 5 installations. The largest single unit has a capacity of 20,000 bpd. An additional 35,000 bpd of SELEX-Asp processing capacity has been licensed worldwide.

Why license SELEX-Asp?

SELEX-Asp is a transformative decarbonization platform that allows the petroleum industry to achieve its emissions reduction targets.


Through a proprietary vapor-solid separation system, SELEX-Asp is used to produce premium decarbonized feedstocks without the need for expensive thermal or catalytic processes, such as coking and ebullated bed hydrocracking.


SELEX-Asp uniquely allows for the clean and selective removal of natural asphaltenes as dry solid granules from petroleum residues. Solid asphaltenes can be safely and easily handled, and used for the production of value-added non-combustion carbon products. SELEX-Asp maximizes the yield of decarbonized oil that can be subsequently processed using low-cost packed bed hydroprocessing.

SELEX-Asp in a Refinery

Yuan, B., Tang, Z., Chung, K.H., Wei, Q., Sun, X., Zhao, S. and Xu, C., “Asphaltenes Extraction Treatment Yields Advantaged Hydroprocessing Feedstock”, Oil & Gas J., June 6, 2016, 70-77.

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Midstream Deployment

SELEX-Asp can be implemented near the primary production source, serving as a key process in an upgrading or partial upgrading facility. Decarbonized oil from SELEX-Asp exhibits enhanced flow characteristics such as lowered density and reduced viscosity. This allows for pipeline transportation with significantly reduced diluent requirements, which reduces pipeline transportation costs while liberating additional pipeline capacity in existing infrastructure. 

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Expand a Refiner's Flexibility to Process Heavy Crudes

Asphaltenes are the only refractory oil constituent to refinery processing. Once asphaltenes are removed, the remaining oil can be processed in conventional refining processes. SELEX-Asp expands the refiner's flexibility by turning low-value, difficult-to-process heavy crude fractions and derivatives into generic refining feedstocks. SELEX-Asp is a key process for enabling a refiner to economically produce a product slate that is compliant with IMO 2020 low-sulfur regulations.

While SELEX-Asp increases the yield of fungible oil and reduces the environmental footprint of an existing refinery, it also reduces hydrogen and catalyst consumption, which are major operating costs for processing heavy feedstock. SELEX-Asp can significantly simplify and debottleneck refinery operations when retrofitted to replace conventional solvent deasphalting, visbreaking, coking, and residue hydroconversion processes.

Competitive Advantage

SELEX-Asp offers the following advantages over conventional alternatives:


  • Maximize liquid yield from petroleum residue

  • Reduce capital and operating costs

  • Smaller and simpler extractor design

  • Higher energy efficiency

  • Lower solvent requirements

  • Deeper and cleaner separation

  • Enhanced mass transfer in extractor

  • Asphaltenes removed as dry granules and easy to handle

  • Creates feedstock suitable for the production of low sulfur consumer products

  • Achieve net-zero emissions

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SELEX-Asp Projects

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SELEX-Asp for

Midstream Deployment

  • Increased Product Value

  • Increased Effective Pipeline Capacity

  • Expanded Markets

SELEX-Asp for

Refinery Deployment

  • Lower Carbon Footprint

  • Increase Refining Margins

  • Add Processing Flexibility

Interested in licensing SELEX-Asp?

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