Oligomerization - Oil Refining

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Axens can offer a large range of simple, robust and flexible processes to address the market demand:

Polynaphtha™, Selectopol™ and PolyFuel® are Axens technologies which oligomerize 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.
FlexEne™ is an innovative combination of two well-proven technologies: Fluidized catalytic cracking (FCC) and Oligomerization to expand the capabilities of the FCC process which is the main refinery conversion unit traditionally oriented to maximize gasoline and at times propylene production.

Process Technologies

Polynaphtha™

Polynaphtha™ is one of the indirect alkylation processes upgrading low-value C₃/C₄ cuts from FCC / SC into gasoline and middle distillates by oligomerization of the light olefins contained in the C₃/C₄ cuts.

In the Polynaphtha™ process, propylene and/or mixed butenes are oligomerized catalytically in a series of fixed bed reactors. Conversion and selectivity are controlled by reactor temperature adjustment while the heat of reaction is removed by feed effluent heat exchange and intermediate reactor cooling. The reactor section effluent is fractionated producing LPG raffinate, gasoline and middle distillate fractions such as kerosene or diesel.

The Polynaphtha™ technology is well suited for revamping existing phosphoric acid polymerization units.

Almost complete olefins conversion & High RON gasoline fraction

Environmentally friendly catalyst

Simple and low cost fixed bed process

Commercial Bulletin

Related Offer

Modular Unit

Selectopol™

The Selectopol™ process is a variant of the Polynaphtha™ process using the same catalyst but at lower severity to convert selectively the isobutene portion of an olefinic C₄ fraction to high octane, low RVP gasoline blending stock or to enrich Trimethyl Pentene stream for petrochemical applications.

Selectopol™ technology provides a low-cost means of retrofitting existing MTBE units or debottlenecking existing alkylation units by converting all isobutene and a small percentage of the n-butenes, with no need for additional isobutane. Selectopol™ is an alternative scheme for alkylation feed preparation without alcohol handling. Selectopol™ technology is also foreseen to avoid or reduce MTBE production in C₄ complex.

Enriched n-butenes raffinate of Selectopol™ is ideally sent to Alkylation, Methyl Ethyl Ketone (MEK), Metathesis or Dimersol-X™ process unit, without any pretreatment.

More than 20 Selectopol™ and Polynaphtha™ units have been licensed by Axens

Almost complete isobutene conversion while preserving N-butenes and Very High RON gasoline

Environmentally friendly catalysts

Commercial Bulletin

Related Offer

Modular Unit

PolyFuel®

PolyFuel® technological service is an innovative technology aimed at maximizing middle distillates production by converting light olefins from LPG and gasoline into distillates at minimum cost. PolyFuel® can accept the full range C5-C9 olefinic cut produced downstream of the FCC.

PolyFuel® technology’s objective is to tackle unbalanced gasoline/middle distillates slates while reaching tighter products requirements.

In the PolyFuel® process, light olefins are oligomerized catalytically in two fixed bed reactors in series. Conversion and selectivity are controlled by reactor temperature adjustment while the heat of reaction is simply removed by feed-effluent heat exchange. The reactor section effluent is fractionated producing gasoline depleted in olefins and middle distillates fractions. The gasoline fraction is recycled to the reaction section to enhance middle distillates production.

PolyFuel® technology is the result of more than 60 years of commercial experience in the fields of olefins conversion into fuels

Moderate investment and utilities consumption

Environmentally friendly solid catalyst regenerable several times

Commercial Bulletin

Related Offer

Modular Unit

FlexEne™

Axens has developed the new FlexEne™ technology to expand the capabilities of the FCC process which is the main refinery conversion unit traditionally oriented to maximize gasoline and at times propylene production.

FlexEne™ is an innovative combination of two well-proven technologies: Fluidized Catalytic Cracking (FCC) and Oligomerization (Polynaphtha™). Combined in an innovative way, they can significantly improve product flexibility to control the balance of propylene, gasoline and diesel production with a low capital investment. This FLEXibility is achieved by selective oligomerization of light FCC alkENEs (olefins) for recycle cracking in the FCC.

By adjusting the catalyst formulation and operating conditions, the FCC process is able to operate in different modes: Maxi Distillate, Maxi Gasoline and High Propylene. This provides the product flexibility required by the market.

7 references for FlexEne™ recorded since its introduction

Proven Flexibility & Simplicity

High Return on Investment

Catalysts & Grading Materials

Catalysts

Oligomerization Catalysts

Oligomerization technologies achieve high conversions of light olefinic fractions into higher value gasoline and middle distillates in association with dedicated catalysts specially developed for these applications.

Adsorbents

Drying Series Adsorbents

Water removal applications are widely encountered in the industry sector. Activated alumina and molecular sieves stand at the forefront of the several different materials available on the market.

Adsorbents

Purification Series Adsorbents

Material specially developed to achieve your feedstock’s specification requirements.

Adsorbents

Sulfur Removal Adsorbents for Oil, Gas & Petrochemicals

Hydrogen sulfide (H₂S), COS, mercaptans or sulfides are common contaminants that must be removed from various gases and liquids such as natural gas, NGLs, LPGs, cracked gases, olefins or biogas.

Consulting, Studies & Audits

Axens offers a customized approach, including tailored studies, audits and consulting services, covering technical and operational challenges.

Unit Revamps & Retrofits

You face many challenges, which include operating in a safe, reliable and environmentally sound manner while responding to changing markets dynamics.

Modular Units

A modularization strategy offers superior benefits versus on-site manufacturing. During the last 40 years, Axens has supplied over 500 modular units, both onshore and offshore, providing tailor-made designs according to client project specifications.

Customer Training

Designed for all Axens technologies, dedicated to operators & engineers, Axens offers customized training solutions to all our licensees, covering the whole range of Axens technologies.

Technical Support & Performance Management

Axens is fully committed to be your partner and provide assistance and support during your project lifecycle, from conception to start-up & running operations.

Dimersol-G™

Axens Solutions Dimersol-G™ process transforms light olefins fractions such as propylene to high quality gasoline called Dimate with low boiling point and high octane properties.

The C₃ feeds are generally the propylene cuts from fluid catalytic cracking units. The Dimersol-G™ process is suitable for isolated refineries without petrochemical outlet for propylene.

Dimersol-G™ gasoline is a proven and high quality gasoline pool component

Dimersol-G™ is a unique low cost process for gasoline production in isolated refineries where no petrochemical output is available for the propylene C3 cut

39 units under license (including Dimersol-X™)

Dimersol-X™

Axens’ Dimersol-X™ process transforms butenes to octenes that are ultimately used in the manufacture of plasticizers via isononanol (isononyl alcohol), and diisononyl phthalate units. Butenes enter the Dimersol-X™ process, which comprises three sections: reactor, catalyst removal and separation.

As shown in the figure, in the reactor section, dimerization occurs in multiple liquid-phase reactors (1) employing homogeneous catalysis and an efficient recycle mixing system. Difasol reactor might be added in order to boost conversion and octene yield through use of ionic liquid. The catalyst is generated in situ by the reaction of components injected in the recycle loop.

The catalyst in the reactor effluent is then deactivated in the neutralization section and separated (2). Section (3) separates unreacted olefin monomer and saturates from the product dimers while the second column (4) separates the octenes. A third column can be added to separate dodecenes.

39 Dimersol™ units treating various olefinic C3 and C4 cuts have been licensed

Commercial Bulletin

Catalysts & Grading Materials

Catalysts

Oligomerization Catalysts

Adsorbents

Drying Series Adsorbents

Water removal applications are widely encountered in the industry sector. Activated alumina and molecular sieves stand at the forefront of the several different materials available on the market.

Adsorbents

Purification Series Adsorbents

Material specially developed to achieve your feedstock’s specification requirements.

Adsorbents

Sulfur Removal Adsorbents for Oil, Gas & Petrochemicals

Hydrogen sulfide (H₂S), COS, mercaptans or sulfides are common contaminants that must be removed from various gases and liquids such as natural gas, NGLs, LPGs, cracked gases, olefins or biogas.

Consulting, Studies & Audits

Axens offers a customized approach, including tailored studies, audits and consulting services, covering technical and operational challenges.

Unit Revamps & Retrofits

You face many challenges, which include operating in a safe, reliable and environmentally sound manner while responding to changing markets dynamics.

Modular Units

Customer Training

Designed for all Axens technologies, dedicated to operators & engineers, Axens offers customized training solutions to all our licensees, covering the whole range of Axens technologies.

Technical Support & Performance Management

Axens is fully committed to be your partner and provide assistance and support during your project lifecycle, from conception to start-up & running operations.

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