Insights from industry

Measuring the Activity and Selectivity of Catalysts

Simon Yunes, Senior Application Scientist at Micromeritics, talks to AZoM about using the PID Effi Microactivity Reactor to measure the activity and selectivity of catalysts.

Could you provide our readers with an overview of the PID Effi Microactivity Reactor and how it works?

The Microactivity-Effi reactor is an automated, high-pressure, fixed-bed catalytic reactor that includes all valves and process layout inside a hot box to efficiently preheat reactants and to avoid condensation of volatile products. This equipment has been designed as a universal basic instrument that can be modified; it features various configurations and options for upgrading the unit to meet the researcher requirements.

The basic unit includes the reactor (up to 1000 oC) and valves inside the hot box, 3 mass flow controllers (MFCs), a micro-regulation pressure control system (up to 100 bar +/-0.1 bar standard), and a high-pressure liquid/gas separator with very low dead volume. All common elements are designed to work in continuous mode. A six-way valve makes it possible to bypass the reactor before a reaction starts while stabilization and feed analysis are taking place.

The main advantage of the Microactivity-Effi reactor is its reproducibility, a result of the patented control systems specially developed for this particular use.

Why is it important to test a new catalyst for activity and selectivity?

After preparing and characterizing a catalyst at micro scale (few mg only) it must be tested for its activity and selectivity for its intended reaction. If undesirable products are obtained, the catalyst can once again be prepared without having to spend a large amount of money. In other words, the EFFI microreactor allows testing of small quantities of catalysts that can yield a very effective and economic catalytic process.

Could you provide some examples of reaction types which the Effi Microactivity Reactor can accommodate?

Both simple and complicated reactions can be carried out using the EFFI microreactor. Hydrotreating, isomerisation, hydrocracking, hydrogenation, and reforming are a few examples.

The most complicated reaction carried out by the EFFI microreactor is Fischer-Tropsch synthesis where the product is a mixture of two non-miscible liquids, water and hydrocarbons. The EFFI has the ability to separate the water from the hydrocarbons online.

What are the main advantages of using the Effi Microactivity Reactor compared to conventional systems for collecting catalyst activity?

Reactors that were used in the past up to just a few years ago were primarily made of glass and could not work at high pressure. Currently, activity testing must simulate the high pressure and temperature of industrial conditions. Although other high pressure reactors are now available, product collection still remains to be an issue.

While other systems must collect product for days or even weeks before compositional analysis can be conducted, the EFFI allows the collection and analysis of product almost instantaneously. This means that the initial activity and all subsequent activity is monitored and used for kinetic studies. Collecting products on line allows the operator to follow the activity and selectivity of the catalyst as a function of analysis time.

Could you outline the two different dual reactor configurations which are available?

There are two options available for the EFFI when a second reactor is installed. The first configuration is called the EFFI DUO which is supplied with two furnaces for two reactors that can operate either in series or one at a time.

The second option, the EFFI TWIN, differs from the EFFI DUO by adding an extra six way valve to the system. This allows the same operation as the EFFI DUO with the added ability to regenerate the spent catalyst on one reactor while the other performs standard activity testing.

Does the Effi Microreactor comes with any optional features?

The EFFI reactor can be updated to run with many different possible configurations. For example, if a reaction requires liquid reactants it is advisable to flow the liquid from the bottom of the reactor instead of from the top. Adding a six way valve to reverse the flow ensures complete wetting of the catalyst bed.

Additionally, adding a calibrated volume loop with a selection valve allows for characterization of the catalyst at high pressure by the pulse chemisorption technique.  This option is called the Micro Catalyst Characterization and Testing Center (MCCTC).

Which are the main industries which benefit from using this instrument?

All research centers that develop catalysts for the oil refineries, catalyst manufacturers, chemical engineering laboratories, pure chemical schools, petrochemistry industries and many others.

In which countries do you currently distribute of the PID Effi Microactivity Reactor to? Are there any plans to expand the distribution to other areas of the world in the future?

Micromeritics/Particulate Systems distributes the EFFI worldwide except for in Spain, France, Brazil, and India where PID Eng & Tech. has direct sales.

Where can our readers find out more information about the PID Effi Microactivity Reactor?

At you can find informative videos, brochures, application notes, publications, and journals with additional information about the EFFI microreactor.

Simon Yunes

About Simon Yunes

Simon Yunes received his B.S. degree in Chemistry from the Central University of Venezuela.  He received both his M.S. and Ph.D. degrees in Physical Chemistry from Catholic University of Louvain, Louvain-La-Neuve, Belgium.

Simon is recognized worldwide for his contribution to the field of adsorption and the application of adsorption techniques to the characterization of solids, particularly catalysts.

Simon joined Micromeritics in May 1984, where he held the position of Senior Application Scientist, conducting experiments on adsorption, assisting the development of new products and writing application notes. His primary function at Micromeritics was to support customers worldwide with their applications, and to find or assist in developing new technologies to meet the needs of customers.

From 1992 to 1996 Simon managed a Micromeritics laboratory at the Venezuelan Research Institute (IVIC) in Caracas, Venezuela. From 2004 to 2009 Simon supervised the Catalyst Characterization Laboratory at the Venezuelan Petroleum Institute INTEVEP. In September 2009, Simon returned to the Micromeritics headquarters in Norcross, Ga, where his primary responsibility is the support of customers worldwide in their application of Micromeritics technologies.

Disclaimer: The views expressed here are those of the interviewee and do not necessarily represent the views of Limited (T/A) AZoNetwork, the owner and operator of this website. This disclaimer forms part of the Terms and Conditions of use of this website.

Alexander Chilton

Written by

Alexander Chilton

Alexander has a BSc in Physics from the University of Sheffield. After graduating, he spent two years working in Sheffield for a large UK-based law firm, before relocating back to the North West and joining the editorial team at AZoNetwork. Alexander is particularly interested in the history and philosophy of science, as well as science communication. Outside of work, Alexander can often be found at gigs, record shopping or watching Crewe Alexandra trying to avoid relegation to League Two.


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