Catalyst Services

Throughout Australasia STM provides Catalyst services with Porocel LLC. Services are designed to help refining, petrochemical, and gas processing plants get the most out of their catalysts and adsorbents. Rejuvenation and regeneration services restore catalyst activity for reuse. Spent hydroprocessing catalyst can be acquired and processed either for reuse or metal reclamation, helping our customers maximize value and minimising waste.

Porocel's ActiCAT® presulfurization process can lead to quicker startups and virtually eliminates the risk of metals reduction.

Length grading technology offers an efficient, low cost solution to pressure drop problems, and density grading technology enables the reuse potential of CCR catalyst providing significant savings on purchasing new catalyst.

Porocel offers HPC worldwide Technical Services including design of reactor.

Catalyst Rejuvenation and Regeneration

Catalyst Rejuvenation

Excel® Rejuvenation Restores Regenerated Catalyst Activity to Near Fresh.

Excel rejuvenation technology is applicable to most hydrotreating catalysts and consistently restores relative volumetric activity (RVA) to >95%. This patented process is available for both Type 1 and Type 2 catalysts, making it an excellent alternative to fresh catalyst for most hydrotreating applications.

Excel rejuvenation can be performed on your catalyst as a post-regeneration process. First, Porocel will evaluate your spent catalyst to ensure sufficient quality for rejuvenation and provide an estimate of final rejuvenated activity. The catalyst’s quality will be re-evaluated after regeneration and again after rejuvenation to confirm adequate activity.


Excel rejuvenated catalysts can provide performance and cost benefits in a wide variety of hydrotreating applications, including:

  • Mild applications such as straight-run naphtha, kerosene, and low-sulphur diesel. These units can experience significant performance improvements vs. fresh catalysts normally used in those applications.

  • Partial fills in high-severity units. In many cases, Excel rejuvenated catalyst can constitute 50% or more of a ULSD or CFH reactor fill while providing performance equivalent to fresh catalyst.

  • Short cycle runs, which typically underutilize the activity of fresh catalyst. Excel rejuvenated catalyst can provide the desired cycle length at a fraction of the cost.


Porocel has activity tested Excel rejuvenation in combination with more than 20 different catalysts from a variety of manufacturers. In all cases, the relative volumetric activity (RVA) has tested more than 90% that of fresh, and in most cases more than 95%. Both HDS and HDN RVA reflect this significant improvement. 

The RVA’s of some Type 1 catalysts and older generation Type 2 catalysts improve to more than 100% that of fresh.

OptiCat Catalyst Regeneration

MBR (Moving Belt Regenerator) Porocel’s proprietary moving belt regeneration process represents the best possible regeneration solution available in the industry.

  • Inert gas strip of volatile hydrocarbons or water

  • Exact temperature control with fast control dynamics & cooling ability for exotherms

  • Plug flow for identical particle residence times for each catalyst being regenerated

  • Customized regeneration according to unique characteristic of contaminants and catalyst

  • Zone control for optimum conditions of air flow and temperature exposure

  • Minimized physical abrasion of the catalyst

  • Careful cooling of regenerated catalyst to prevent thermal shock

Catalyst is regenerated with minimum deterioration of physical properties such as surface area, pore volume, particle length and undergoes optimum conditions to regain the best possible activity.

ExcelSM Rejuvinated Type 2 CoMo vs Fresh.jpg
ExcelSM Rejuvinated Type 2 NiMo vs Fresh.jpg


actiCAT® ex situ Catalyst Presulphurizuing

Porocel actiCAT® presulphurization is a unique, proprietary process in which sulphiding agent is tightly bound to catalyst in an organic matrix. During the presulphurization process, a range of sulphiding chemicals are generated. These chemicals react with hydrogen over a broad temperature range resulting in a gradual and controlled activation.

Activation of actiCAT® presulphurized catalyst is fast and easy. For a typical hydrotreater start-up, actiCAT® saves about 18 hours compared with in-situ sulphiding. For hydrocrackers and very large hydrotreaters, the time savings can be on the order of several days.

In addition to time savings, actiCAT® presulphurized catalyst eliminates the handling of toxic, odorous sulphiding chemicals and the need for temporary pumping stations. Also, since each catalyst pellet is treated with sulphur, actiCAT® catalyst provides high levels of catalyst activity with minimal chance for metals reduction.

Technical Service

In order to help the refiner enjoy the maximum benefits of actiCAT, we provide technical advice on startup procedures. Onsite technical assistance during startup can be provided upon request and will be charged at cost.

Length & Density Grading

Length Grading

Length grading is used to increase the average particle length of a batch of catalyst (extrudates). Short particles can reduce the void fraction in a catalyst bed and thereby increase pressure drop over the reactor. In order to recover particles of good length, Catalyst Recovery has developed a sophisticated screening technology that allows the separation of catalysts particles with a length up to twice the diameter to be efficiently removed without excessive catalyst losses.

Length grading can be performed on any batch of catalyst or extrudates; fresh, used, or regenerated. Length grading as part of a regeneration job is best performed before regeneration so that short particles are not unnecessarily regenerated.

Density Grading

Density grading separates catalyst particles of similar size based on individual particle density.
CCR reforming units continuously circulate catalyst through the reactor. Catalyst exiting the reactor typically contains about 5% carbon. It is regenerated online and fed back into the reactor. In many units, a small fraction of the catalyst does not circulate through the reactors. This non-flowing “heel” catalyst is held up in the bottom and along the walls of the reactors. Over time, the heel catalyst builds up carbon levels as high as 50%.

Heel-contaminated catalyst cannot be reused because its high carbon content causes temperature excursions in the regenerator tower. When a plant plans to reuse the catalyst removed in a turnaround, there is a strong economic incentive to recover the low-carbon circulating catalyst. If the low-carbon catalyst is not recovered, it must be sent to platinum recovery and replaced with fresh, makeup catalyst at considerable cost.

Density grading can be used to recover low-carbon catalyst contaminated with heel catalyst. Because the heel catalyst has a 40-80% higher density than the low-carbon catalyst, a precise separation can be made.

HPC Technical Services

STM with Porocel Catalyst Recovery Singapore technical services offer

Load Design

Full Hydrotreating reactor load design from top grading (CatGuard®) and bed support (Durocel-222) materials through the main catalyst bed. Porocel technical services assist in selection of regenerated or Excel® rejuvenated catalysts to meet customer specific unit performance objectives with respect to:

  • Feed properties

  • Hydrogen availability

  • Temperature constraints

  • Hydrogen partial pressure

  • Product targets

HPC unit monitoring for a Full Reactor Loading (FRL)

 during cycle, such as:

  • Feed/product review

  • Operating conditions

  • Deactivation analysis

  • End of cycle predictions 


Troubleshoot unique challenges encountered during your cycle:

  • Assist in identifying and minimizing maldistribution

  • Investigate product quality deficiencies

  • Estimate the impact of feed and operational changes to cycle length

Additional services 


  • Loading and start-up advice

  • Catalyst regeneration and Excel® rejuvenation

  • Catalyst presulfurization (actiCAT® and actiCAT Shield®)

  • Catalyst selection and testing