Continuous Flow Reaction Calorimetry: A Novel Tool For Industrial Flow Chemistry

An efficient and safe transfer of chemistry from the laboratory to the plant scale requires process understanding. This understanding is provided by reaction calorimetric studies, an industrial standard practiced for years and typically done in batch operation. With the emerging flow chemistry applications, this standard will be and needs to be extended with flow calorimetry, a new service of Microinnova.

Flow chemistry typically utilizes highly reactive reagents with reaction half-life times in a magnitude of seconds to minutes. Continuous flow calorimetry opens up the possibility to safely measure such fast reactions as well as unstable intermediates. Especially data for process design can be obtained under steady-state operation, which is not possible in batch operation. Non-selective reactions, mainly seen by mixing limitations, may produce different products in continuous flow operation compared to batch and therefore pose a risk in the design of continuous flow processes when basing the safety considerations on batch data. In addition to the thermal data, it is possible to obtain information about reaction times and kinetics in flow calorimetry by a segment-wise temperature or heat flux measurement. Another advantage of flow calorimetry is to generate data automatically at various operation conditions by adjusting flow rates and ratios to screen different stoichiometric conditions.

Microinnova’s Services

At Microinnova, we offer flow calorimetry in a tube-in-tube Fluitec reactor with static mixing elements, all made of Hastelloy. The coolant in an outer shell is held at constant temperature and the reaction media at isoperibolic conditions, whereby a heat profile is measured over the length of the reactor. This operation mode resembles a reaction in a commercial tubular reactor and gives awareness of heat transfer characteristics. Heat transfer characteristics of the reactor and both coolant and reaction media are needed for the measurement.

Operation conditions from 0 – 200°C can be used at a pressure of 10 bar. The device has 10 temperature measurement points within the static mixer to generate a temperature profile. Flow rates are recommended between 20 – 100 ml/min using Reynolds Numbers in the range of 0 < Re < 100 for a good measurement and viscosities of liquid materials from 1 – 120 mPas. Typical reaction times used for measurements are between <1 s and approximately 2 min. If the reaction time is longer than the fluidic residence time, a quench is needed to stop the reaction from progressing. For unfinished reactions, a quantitative analysis of the converted species is needed to base the reaction heat on consumed or formed reactants. Continuous flow calorimetry is seen as a key technology for process development and safety analysis at Microinnova.

Contact our expert team to find out more!

80 Flow Chemistries and Flow Processes, Part 2: Continuous Halogenation

Microinnova has performed different halogenation reactions in the lab and has gained significant experience. For example, halogenation of aromatic systems with elemental halogens (fluorine, chlorine, bromine, iodine) or hydrohalogenation with hydro-halides has been carried out. “Flow process design and scale-up for safe and selective halogenation is a core competence of Microinnova.” says Dirk Kirschneck, Strategic Director of Microinnova.

Hydro-halogenations of double bonds and epoxides were realized with hydrogen-halides, as well as halo-exchange reactions. By mixing chloro-aliphatic and chloro-aromatic substances with HF-complexes, fluorinated products were obtained. Pressurized reactors operating at high temperatures were used for performing halo-exchange; continuously operating systems are one of the safest methods of manufacturing chemicals. For the safe handling of halogens at lab scale, chlorine and bromine generators were used to provide a steady supply of the toxic reagents. Highly reactive reagents such as sodium hypochlorite can be formed in-situ using flow technology and offer easier handling and storage. When combined with inline purification, they can be used consecutively as reagents for the desired chemistry. By providing stochiometric ratios of the reagents, high selectivity can be achieved e.g. for the selective oxidation of secondary alcohols in the presence of primary alcohols.

Photohalogenations, as well as oxidation reactions, were carried out with the supplied reagents. Such generators could also be realized at pilot and small production scale, in order to avoid storage of the toxic reagents. Such generator approaches could also be realized for even more dangerous substances such as halo-azides and halo-cyanides. Microinnova can assist and provide such generator systems.

Trials at pilot stage have been successfully performed with elemental fluorine and with elemental bromine in Corning reactor systems. In the future, both pilot trials may be realized at production scale.

Contact our expert team to learn more about our competence in halogenation and our other services!

Continuous Manufacturing Modular API Plant

CordenPharma Chenôve SAS has commissioned a continuously operating modular API and intermediates synthesis plant that they recently put into operation to realize the benefits of process intensification. It consists of two feed modules with two dosing lines each, and four dosing lines altogether. Two of those dosing lines are made of Hastelloy, one is made of stainless steel and the other dosing line is free of metal. Each dosing line is designed for a flow between 15 and 250 ml per minute at 20 bar.

Furthermore, there is one reaction module and a quench module, both of which can supply a maximum of 500 ml per minute at 20 bar. The four thermostats enable the use of different temperature levels in different stages of the process. The plant can operate with liquids, gases, and suspensions as feed streams, and it can be used with various continuous reactor technologies while operating automatically.

Our modular design provides smart process flexibility enabled by a standardized and uniform exchange of functionalities for multi-purpose processes and mobile installation in a smart manufacturing environment based on walk-in fume hoods. Achieving full customer satisfaction, Microinnova’s engineers are delighted to have been able to once again provide more flexibility and increased capacity to a valued client.

80 Flow Chemistries and Flow Processes, Part 1: Polymers

Based on nearly 20 years in the field of flow process design the team at Microinnova has executed more than 200 projects in flow chemistry. Different types of polymerization reactions have been executed including free-radical and ionic polymerizations, as well as polyester and oligomer synthesis. We address product quality and safety issues since these types of exothermic reactions benefit from a large heat transfer efficiency and excellent mixing.

Their large exothermicity is of significant safety concern. Uniform processing conditions have a huge impact on the quality of the material such as molecular mass distribution. Projects with polymers have been executed for end-capping, exchange of functional groups, and cross-linking, for example. Radical starting materials, as well as urethane and dicarboxylic monomers have been synthesized. The continuous reaction of back-bone structures used in formulations (e.g., gel structures) improves the level of product quality in addition to the interfacial area. Microinnova has experience in handling materials with viscosities of up to 100,000 mPas. Polymer processes benefit from a specific cooling surface of up to 200 m2/m3 with a high k-value and narrow residence time distribution.

Microinnova Strengthens the Field of Digital Processing…

…by kicking off the Project “PharmComplete” using Digital Twin, Model-Predictive-Control and PAT strategies.

A shift towards more efficient and controlled processes is taking place in the pharmaceutical industry with process analytical technologies, continuous manufacturing and advanced process control strategies being central elements. While different suppliers make plug and play lines available, especially in the field of solid dosage manufacturing, the change to completely monitored and automated processes is being implemented only slowly. Process data is still mainly used for manual operation decisions and out-of-specification product is discharged. Model-based predictive control is rarely applied in an industrial environment. Labor-intensive quality control, variable product quality and inefficient utilization of resources is common.

PharmComplete’s goal is to develop a digital twin for an integrated pharmaceutical manufacturing line, from API synthesis to downstream processing. Process models will be developed for all unit operations or pre-existing models will be adapted to the specific conditions and materials. With a machine learning approach, a focus will be on model simplification for easier utilization in an industrial environment. The digital twin enables the execution of process simulation and control. Intelligent process control based on process information generated from real-time process data enables robust processing, reduction of waste and constant high product quality assured during the production campaign. RCPE with TU GrazUniversity of Grazevon GmbH and Microinnova Engineering GmbH are working closely together on building new routes for digital processing and Industry 4.0. 

Microinnova Sponsors Award for Outstanding Process Intensification Work Towards CO2 Reduction

We were honored to have the opportunity to sponsor the 2021 EFCE Excellence Award in Process Intensification! The recipient of this award was Dr. Evangelos Delikonstantis whose Ph.D. work, titled “Plasma-Assisted Non-Oxidative Methane Coupling to Olefins”, looked into how methane can be converted to ethylene using a nanosecond pulsed plasma. Dr. Kirschneck, who presented the award, and Dr. van Gerven, who is the chairman of the working party “Process Intensification”, were very interested in Dr. Delikonstantis’ subsequent presentation. He noted that beyond the non-oxidative methane coupling to ethylene, the findings demonstrate the potential of nanosecond pulsed plasma for catalysis and should pave the way to other important chemical conversion reactions. If powered by renewable electricity, the process could pave the way for novel low-carbon ethylene production processes, with an estimated carbon footprint of 1.3kg of CO2-equivalent per kilogram of ethylene.  

More infos on this outstanding work in this press release.

Intensification Boost for Enzymatic Liquid/Gas Processes by Means of Continuous Flow Processing


O2-dependent biotransformation reactions have proven difficult in fine chemical manufacturing due to the mass transfer limitations of supplying O2 to the enzymatic reaction, hence affecting the level of efficiency achieved. Previous research has shown that enzymatic processes involving gases have a high potential for process intensification by implementing continuous flow processing technology.


In a cooperation between acib and Microinnova Engineering GmbH, with more than 15 years of experience in flow chemistry it has been proven that process intensification can be applied using continuous flow processing. This technology offers a comprehensive solution with a pressurized system that results in a significantly higher level of dissolved oxygen. A continuous flow reactor pressurized to 34 bar enables biotransformation to be conducted in a single liquid phase and significant increase of enzymatic activity was detected already at 10 bar. For glucose oxidase, the intensification factor for enzyme activity was up to 2.5 and amino acid oxidase showed an intensification factor up to 6 for the enzyme activity. High product concentration has been demonstrated with the concentration being 6 to 10 times higher at 34 bars compared to atmospheric pressure. See also Bolivar J.M., Mannsberger A., Thomsen M.S, Tekautz G., Nidetzky B. (2019) Biotechnology and Bioengineering, 116(3), 503–514.

Find out more in this acib newsletter!

Corning and Microinnova Celebrate Opening of Advanced-Flow™ Reactor Qualified Lab

Corning Incorporated and Microinnova recently celebrated the opening of the Corning® Advanced-Flow™ Reactors (AFR) Application Qualified Lab (AQL) at their facility near Graz. Application qualified labs enable AFR customers to effectively access continuous-flow demonstrations, experimental trials, feasibility testing, and chemical reaction process development.

Corning currently has one other AQL in Europe at the University of Liège, which opened in 2017, as well as several operational AQLs worldwide that support the business. These regional facilities provide customers with convenient access to AFR Technology.

Microinnova is an innovation-based company focused on process development, design, and the realization of continuous pilot lines and manufacturing plants. Based on their critical parameter approach, Microinnova intensifies synthesis, as well as work-up and formulation processes using a wide range of different technologies leading to high-performance processes.

Microinnova has recently established a fluorine lab at their facility in Graz and are utilizing Corning’s G1 Silicon Carbide (G1 SiC) reactors to process highly toxic and corrosive chemicals in an inherently safer, more efficient way that can help customers in pharmaceutical, fine and specialty chemicals industries create a better end product.

“We’ve worked closely with Microinnova over the last few years, and the core values of innovation and commitment to inherently safer continuous flow chemistry really makes this collaboration a great fit for both companies,” said Alessandra Vizza, regional business director, Corning® Advanced-Flow Reactors. “Corning’s equipment and materials enable more stable reactions and can reduce inherent risks associated with handling/processing hazardous chemicals – which is really what the core of AFR Technology is all about.”

The location of this laboratory will help Microinnova provide broader reach to their customer base within the pharmaceutical, fine and specialty chemicals industries in Europe.

“We operate to strengthen our capabilities in the fields of fast, exothermic or highly corrosive processes for development as well as for manufacturing plant realization as a system integrator,” said Dr. Dirk Kirschneck, strategic director, Microinnova. “Based on the strong collaboration between the two companies since 2007, we are looking forward to continuing to work with Corning on future programs as one of their Application Qualified Labs.”

In addition to its AQLs, a critical part of the AFR business’ model for more than a decade has been its commitment to educating the regions where it operates.

“In Europe, we’re actively trying to educate both at the academic and industrial level on the value of continuous flow technology,” Alessandra said. “We’re hopeful that our broad product offerings as well as collaborations with companies like Microinnova will help us in this effort.”

Modular Plants: Speed as the Key Success Factor for Chemical Businesses in the Future

We expect that speed and flexibility will be success factors for chemical businesses in the future. The example of Ryan Air illustrates the importance of focusing on value generation for the customers and how innovation in a business model can achieve it.

Modular plants offer the best processing solution giving both flexibility and speed; ownership may not be key in the future. To facilitate this, design modification between the modules and within the modules should be enabled with other aspects considered such as engineered spaces and access for maintenance and modifications. Module Type Package (MTP), a technology offered by Microinnova, enables a Plug-and-Play solution for processing plants (like USB for computers). It is important to also consider the changeover possibilities, physical movement and how the infrastructure is designed so that the equipment fits the process. Furthermore, we also supply plant virtualization where we engage in the pre-testing of process conditions using digital twins/model predictive control, documentation of modifications with an implemented as-built/modified documentation, PAT and pre-HAZOP scenarios. Moreover, we expect that some plants will consist mainly of pre-designed and pre-built package units in the future with a predicted 60-80% of the modules being pre-designed. An exception to this being specific reactors addressing a certain set of critical parameters that are designed bespoke for an individual process. A similar shift has been observed in the automotive industry, where cars are designed based on a platform concept. 

Learn more about how your chemical business can benefit from modular plants! »

Capacity Boost by Batch-to-Conti Debottlenecking

Space economy is a typical issue for debottlenecking batch projects. Since a continuous approach reduces mass and heat transfer distances up to a factor of 100, these solutions can easily be integrated into an existing batch environment. A number of different strategies can reduce or replace batch processing times. For example, a batch processing step can be translated into a continuous plant skid. 

In some cases, the mixing operation or even the reaction itself can be executed while filling the reactor. Reagents, especially hazardous ones, can be synthesized in situ. Large savings can be achieved in the field of acid-base-reactions, since they are characterized by a strong heat release. These kinds of processes can reduce residence times from hours to minutes, since they are limited by the heat exchange which can easily be controlled in a continuous device. Mobility of skids enables a flexible use in connection with different plants. Optimizing mass and heat transfer is an important factor in reducing the costs per kilogram, leading to an increased competitiveness.

Find out more about our debottlenecking capabilities!

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