Unionfining Technology

Process

   The MQD Unionfining process is a family of technologies that offers completely integrated solutions to upgrade difficult, refractory, distillate-range materials to high quality diesel that meets stringent requirements for sulfur and aromatics content, cetane, and cold-flow properties.

Figure 1 shows that Diesel/Gasoil will grow faster than

gasoline

Family of process and catalysts

       The MQD Unionfining process is based on a number of multifunctional catalysts that are optimized to achieve varying product quality objectives. Process configuration and catalyst choice depend on the desired product quality improvement and existing refinery configuration.

Diesel	Current	Future
Sulfur	350 ppm	1 ppm

Desulfurization

     Achieving low-sulfur diesel specifications requires more  active catalysts than used in traditional hydrotreating. UOP uses the latest generation of catalysts to achieve selective desulfurization  ith high yields and minimum cracking reactions. Where more activity is required and denitrification is important, or where some aromatic saturation is needed, UOP offers the latest generation of catalysts, designed for this service.

     When conversion of the heavier fraction of the gas oil feed is critical and the cetane upgrading requirements are modest, UOP will include a base-metal cracking function into the catalyst system.

 Higher cetane – lower aromatics

Meeting some of the new distillate specifications – especially in Europe – that require high cetane and limit total aromatics or poly-aromatic hydrocarbon content will require significant aromatics saturation. Although basemetal catalysts can achieve some degree of aromatics.

saturation, significant aromatics reduction can only be achieved with noble-metal catalysts. Figure 2 illustrates the superior aromatics saturation abilities of noble-metal catalysts.

     UOP recommends using AS-250TM catalyst for aromatics saturation because it exhibits high activity yet shows much lower sensitivity to feedstock sulfur and nitrogen levels than other diesel aromatics saturation catalysts. Improving the cetane of refractory materials – especially cracked stocks such as light coker gas oil or FCC light cycle oil – requires not only aromatics saturation, but also ring opening. 

     The ability of the AS-250 catalyst to improve light coker gas oil cetane by saturating aromaticsand then opening naphthenic rings is illustrated in  figure 3

Improved cold flow properties

  Cold flow properties can be improved by dewaxing using either paraffin isomerization or catalytic dewaxing.Paraffin isomerization is preferred because it achieves higher diesel yield.

     HC-80TM catalyst is a base-metal, zeolitic catalyst that achieves dewaxing by selectively cracking the waxy normal paraffins to naphtha.

MQD Unionfining process description

   The MQD Unionfining process uses either a singlestage or two-stage configuration. The single-stage design is used with most base-metal catalyst applications. 

The two-stage scheme is designed to achieve the highest quality diesel by using a noble-metal catalyst in the second stage.

Commercial experience

     This new approach to high-quality diesel is based on aunique combination of processes and catalysts commercialized by UOP over the past 50 years. More than 50 Unionfining process licenses have been issued in the last decade, with recent distillate activity concentrating on the MQD Unionfining process.

Hydrotreating Catalysts

    UOP’s Unionfining catalysts for hydrotreating process units deliver first-rate, cost effective hydrotreating. They also contribute to low operating costs thanks to their excellent activity and stability. 

        Our Unionfining catalysts can produce low-sulfur diesel fuel, ultra-low-sulfur diesel fuel (ULSD), and blend stock for fuel oil pools. Plus, when regenerated, they can operate for multiple cycles. The production of diesel fuels for low sulfur, high cetane, excellent color, and high color stability has been well demonstrated with Unionfining catalysts. VGO Unionfining catalysts can ensure almost complete removal of feedstock sulfur and nitrogen, and they are therefore a key feature in the pretreatment stage of hydrocracking process units. 

     Unionfining catalysts have been used in more than 650 refining units worldwide. These catalysts can meet the stringent requirements for today’s high-quality products, including the production of feedstocks for downstream processing such as naphtha reforming, isomerization, or FCC and resid catalytic cracking. 

     At UOP, we conduct research and development in support of hydrotreating technology in an ever-changing and demanding market. Our experts will provide technical service to help maximize your return.