Dec-2021

Game-changing catalytic dewaxing: Zeopore reaches 30°C cloud point improvement (ERTC)

Making diesel winter-proof is currently an expensive process as refiners face high diesel yield losses or have to turn to expensive additives or kerosene blending. hte GmbH examined the catalytic dewaxing performance of Zeopore’s proprietary zeolite mesoporisation technology in its high throughput testing facility using industrial feeds and process conditions.

Rob Snoeijs
Zeopore

Article Summary

The results are phenomenal: Zeopore reaches five times lower diesel yield loss at high cloud point or pour point improvements, compared to an industrial reference zeolite. Zeopore reaches a 30°C cloud point improvement while keeping diesel yield loss well below 2 wt%. Furthermore, Zeopore’s catalytic dewaxing innovation reduces capacity-limiting gas formation, improves product slate composition, and maintains favourable zeolite activities and lifetimes.

Zeopore’s unique tunable mesoporisation technology is economically attractive for catalyst manufacturers and refiners, even more in sustainable processes delivering renewable fuels.

Economic dewaxing of diesel and lubricants is challenging
Paraffinic components in standard diesel feedstocks tend to crystallise when temperatures drop below 10°C. The so-called cloud point (CP) is the threshold temperature where a specific fuel starts to become waxy, opaque and less liquid. Dewaxing of diesel and lubricants is necessary for usage in colder operating environments, or during winter periods. Dewaxed products ensure the optimal performance, reduced emissions and prevent malfunction or damage to diesel engines and other machinery. Typically, the aim of dewaxing is to reduce the CP with 30 degrees or even more in arctic environments. As diesels and lubes from renewable sources typically have less favourable cold flow properties, they face an even higher need for dewaxing.

Qualitative dewaxing is a challenging process because it often results in undesired cracking of molecules, which leads to expensive diesel yield loss or undesired gaseous streams. Alternatives for reducing CP include the use of additives or blending with (valuable) other finished products, both expensive routes and offering no flexibility in managing opportunity crudes. From an economic standpoint, the preferred approach is catalytic dewaxing, which is in essence hydro-isomerisation or branching of linear paraffinic components to form branched components with better cold flow properties. A critical condition here is to keep the economics of this conversion under control, especially minimising the diesel yield loss to lighter fractions.

Zeopore optimises zeolite catalyst mesoporisation for dewaxing
The narrow micropore structure of today’s isomerisation-selective zeolite catalysts forms the highest industry standard of dewaxing improvement based on a stable and tunable cloud point improvement. Nevertheless, the zeolite’s narrow micropores also provoke access and diffusion limitations, resulting in undesired side reactions and unwanted products, such as over-cracked molecules in the case of dewaxing. Zeopore adds a secondary level of larger mesopores to conventional zeolites to increase their catalytic efficiency by improving access to the active sites located in the zeolites’ micropores. Zeopore’s innovative mesoporisation process, specifically designed to maximise mesopore formation quality and efficiency, only requires standard unit operations and low-cost ingredients.

Kurt Du Mong, CEO of Zeopore Technologies: “Over the past three years, Zeopore has developed a broad technology toolbox to cost-effectively generate more performant zeolites with custom-made properties. Compared to the reference parent zeolite, Zeopore succeeded in tripling the mesoporosity and optimizing the metal addition of a commercial dewaxing zeolite without compromising its powerful intrinsic properties and stability. We are proud to have demonstrated the catalytic and economic value proposition in the highly relevant dewaxing application. Zeopore is currently negotiating with selected catalyst manufacturers to bring this technology to market.”

The innovative dewaxing zeolites developed by Zeopore are ideally suited for catalytic dewaxing of fossil derived diesels and lubricants, representing two major global markets. Next to that, the emerging markets of renewable fuels and lubricants are growing extremely fast and of high interest to the industry. Dewaxing in this market is imperative because these renewable products have lower cold flow properties than those of fossil-based products. Higher-performance dewaxing at an affordable cost is even more important in light of delivering high-quality renewable fuels.

Zeopore’s catalytic dewaxing breakthrough is industrially viable
To convince the global dewaxing industry, Zeopore has tested a noble-metal containing unidirectional mesoporised dewaxing zeolite in a parallel state-of-the-art 16-fold high- throughput testing unit at hte GmbH in Heidelberg, Germany. The test has been conducted in broad ranges of industrially relevant pressures, temperature and space velocities.

The results demonstrate a real breakthrough in catalytic dewaxing. Figure 1 below shows that at fixed CP improvement, e.g. when considering a gain of 30°C, the mesoporised Zeopore dewaxing zeolite enables a five-fold lower diesel yield, arriving at a diesel loss below 0.06 wt% per degree of CP improvement. This achievement is unseen in the catalytic dewaxing industry. In particular because Zeopore is able to couple the benefits of its high-performance zeolites with a low-cost and tunable manufacturing process.

                                       Feed    Reference    Zeopore

Cloud point / °C             -5         -35
Diesel fraction / wt%     93.8      84.6             92.0
LPG formed / wt%         -           3.2               0.6

Wolfram Stichert, CEO of hte GmbH in Heidelberg, Germany: “We are very pleased that Zeopore has selected hte as testing partner, and that we have been able to contribute to the success of this project with our R&D expertise in this area and our state-of-the-art high throughput technology. hte is glad to have assisted in achieving this milestone, which is a stepstone in Zeopore’s further commercialization in the coming years.”

The test results further show that the observed zeolite dewaxing catalyst does not suffer increased degradation compared to the parent zeolite. In addition, the use of Zeopore’s dewaxing catalyst resulted in much lower gas (LPG) formation (see Table 1). This eliminates the typical capacity reductions in catalyst production faced by catalyst manufacturers and refiners due to excessive gas formation.

Moreover, even when evaluated at a fixed diesel loss, Zeopore’s dewaxing zeolite offers additional advantages: Figure 2 shows you the product slate composition of the lighter fractions, demonstrating a lower degree of gas make, and a more beneficial amount of branched and larger molecules.

Using its innovative tunable toolbox, Zeopore develops mesoporised zeolites for a wide range of applications covering refining, petrochemical, biomass conversion and plastics recycling. These mesoporised zeolites are available through licence or product supply agreements.

The achievements mentioned have been made possible with the support of Flanders Innovation & Entrepreneurship (VLAIO).

For more information contact: rob.snoeijs@zeopore.com

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This short article originally appeared in the 2021 ERTC Newspapers, produced by PTQ / DigitalRefining.

You can view the Day 1 Newspaper HERE
You can view the Day 2 Newspaper HERE