Innovative methods and techniques for chemical transformation

Obiettivo

A.Background

A1.Why a COST Action for this topic?

In order to increase its competitivity, the European chemical industry needs new methods and techniques to produce new and novel products, and to improve processing conditions. Improved technologies essentially mean less energy consuming, less polluting, and more selective chemical processes. The concept "innovative methods and techniques" is used here to describe methods and techniques that are presently under study at a fundamental level, which have already given interesting and promising results, which in some cases already have applications in industry, but for which it is clear that many other domains of application are conceivable. "Innovative techniques" also include the possibility to combine different techniques, i.e. technical procedures involving extreme or non-classic conditions, in order to obtain new effects that will be more than the sum of the effects obtained with the different techniques when employed individually. Finally, "innovative methods and techniques also include the use of experimental conditions which are non-classical at least in industry, but which could lead to less energy consumption, less pollution (clean chemistry), and higher selectivity in chemical processes.

Combined efforts from scientists and engineers from related fields in this new Action will provide the basis for future challenges in which innovation will be a key aspect in order to control chemical transformations. It is therefore desirable that in the new action the projects should obtain a more interdisciplinary character, by bringing chemists and engineers, chemists and physicists and chemists and biologists together to interact on the topic of innovative methods and techniques for chemical transformations. These will include methods and techniques such as supercritical fluids, high pressure, ultrasound, microwaves and pulse-plasma discharges, as well as combinations of these among each other and with electrochemical, photochemical and radiochemical techniques.

The experience gained within COST D6 "Chemical processes and reactions under extreme or non-classic conditions" has shown that scientists from different scientific disciplines, subject areas and countries, can efficiently collaborate under a carefully managed COST umbrella. This new Action will allow them to develop an area that could have a major impact on world science and to pioneer advances in an area which is becoming increasingly important in chemical process development and management.

A2.Status of Research in the Field

The research in this field has developed strongly over the last few years. This was evidenced by a number of workshops, conferences and group meetings that dealt with different aspects of new methods and techniques for chemical transformations. Although much of the reported work was of a fundamental nature, for instance as presented at the two COST D6 Workshops in Lausanne (1993) and Lahnstein (1995), work in applied areas involving supercritical media and ultrasound has made good progress and is being carried out on a pilot plant scale. The advances in the various areas have encouraged participants of the present D6-Action to contribute to a monograph with the title "Chemistry under extreme or non-classical conditions" which is presently in print with Spectrum/Wiley and will appear during the summer of 1996. A few examples of new methods and techniques for chemical transformations are now discussed in more detail.

Supercritical fluids such as supercritical CO2 and supercritical H2O are clear-cut examples of reaction media with many potential applications, which are far from the extraction procedures commonly used in food and aroma chemistry. A large number of chemical transformations can be performed in these media and the coupling of supercritical fluids with photochemistry, electrochemistry and catalysis, looks very promising. The supercritical fluid can act as solvent, but can also act simultaneously as solvent and reactant. The reactions can come from organic, inorganic and organometallic chemistry. Many problems related to chemical engineering, but also concerning fundamental physical chemistry have yet to be solved before it will be possible to determine the various fields of application of supercritical media. It is however obvious that these media could solve some if not many problems associated with solvent pollution and hazardous waste treatment.

It is known that pressure effects can strongly modify the structure and function of biological macromolecules. Food processing by high pressure is already a common procedure in Japan. It is surprising to see how this application, and many others related to the use of high pressure in chemistry and "in vitro" biochemistry, are still underdeveloped in the European industry. The proposed action could promote know-how transfer if specialists in chemical engineering could be involved. As in the case of supercritical fluids, the scale-up problems remain difficult and will require a collaboration between physicists, physico-chemists and engineers.

The use of ultrasound to promote reactions, to prepare catalysts, to polymerize or depolymerize, is well documented in the literature, but strangely enough, the physical basis for the observed phenomena is still in discussion. Mechanical effects of ultrasound are certainly due to acoustic streaming, acoustic microstreaming and also jetting, when a cavitation bubble implodes near any interface. The effects of ultrasound on heterogeneous reactions are essentially related to these phenomena. Nevertheless, the origin of the effects of ultrasound on homogeneous media, and particularly the formation of radicals, frequently observed when a liquid is irradiated by ultrasound, remains a subject of debate. The highly non-linear nature of acoustic cavitation, and therefore of sonochemistry, necessitates a strong collaboration between chemists and physicists. The scale-up problems encountered in sonochemistry are specific and difficult especially in the 20-30 kHz frequency range where the wavelengths of the longitudinal pressure waves are comparable to the reactor size. Collaboration between chemists, physicists and engineers is necessary to handle such problems. Similarly, the high frequency domain requires complementary work to determine if industrial applications are conceivable in this frequency range.

Microwave chemistry and plasma chemistry are other examples of innovative or potentially innovative methods and techniques for chemical transformations at the industrial level. The use of non-classical solvents like water to perform organic reactions, or organic solvents to perform enzymatic reactions must also be cited. In these last domains, the fundamental know-how in Europe is good and scale-up problems can be solved by structured networks of scientists.

Finally, new research areas of great interest can be found at the interface between the various domains outlined above. High pressure gas phase chemistry is directly related to chemistry in supercritical fluids. The conditions that arise in a collapsing cavitation bubble seem to be similar to those that arise in a plasma. The shell surrounding the imploding cavitation bubble could be in a supercritical state. Chemical transformations of macromolecules by high temperature, high pressure and also by ultrasonic irradiation and g-irradiation present interesting similarities but also significant differences. The coupling between, on the one hand, electrochemistry or photochemistry and, on the other hand, supercritical fluid chemistry of sonochemistry are fast developing subjects with numerous challenges. In all these cases, innovative techniques and technologies are already under development or will be developed in the near future.

Without doubt, a COST Action oriented towards methodological and technological problems could strongly support the European chemical industry to remain competitive and to reach the standards required by anti-pollution and energy saving European policies. A multi-disciplinary action focusing on innovative methods and techniques for chemical transformations therefore seems very appropriate and highly desirable.

A3.Relationship with other European Programmes and Activities

The experiences gain in COST D6 led to this proposal and can be considered as an integrated component. Over the past few years there has been a steady increase in the awareness amongst chemists in Europe for innovative methods and techniques in the study of chemical transformations. Two workshops organized within the D6-Action focused on "Chemical processes and reactions under extreme or non-classic conditions" (Lausanne, 1993) and "Chemistry under extreme or non-classic conditions" (Lahnstein, 1995). There are national programmes in several COST countries, e.g. Germany has initiated a "Schwerpunktprogramm" for chemistry under supercritical conditions. There is also a working group on "High pressure chemical engineering" that meets regularly to discuss progress in the application of high pressure techniques.

There are yearly meetings of the European High Pressure Research Group, the next one will take place in Leuven (B) later this year. An international symposium on High Pressure Chemical Engineering will be held in Z_rich (CH), and a meeting on progress in the application of supercritical fluids will be held in Nottingham (UK) later this year.

In Germany, the German Society of Sonochemistry has been launched during a meeting organized by DECHEMA in Frankfurt (November 1994). Meetings of the European Society of Sonochemistry accompany the activities of the networks (Blankenberge, September, 1994, Cambridge, July 1996), and their two recent COST Workshops (Blankenberge, September 1994, Berlin, September 1995).

The high pressure enzymologists have organized six international meetings in 1994 and 1995, in which members of their networks participated actively as organizers and lecturers.

B. Objectives and Benefits

B1. Main Objective

The main objective of this action is to stimulate research activities focused on the application of innovative methods and techniques for chemical transformations at a fundamental and applied level. Different methods and techniques involving extreme or non-classical conditions should be investigated and applied at an industrial level. This will require the close cooperation of engineers, chemists and physicists. The ultimate aims are lower energy consumption, less pollution (clean chemistry) and higher selectivity in chemical transformations.

B2.Secondary Objectives

1.The application of high pressure conditions in chemical transformations can lead to a more effective control over chemical syntheses, product selectivity, and chemical reactivity. New synthetic processes, new materials and an improved understanding of chemical reactivity are to be expected.

2.The application of supercritical conditions can lead to new separation technologies, non-organic solvent processes, milder reaction conditions, improved transport phenomena, higher turnover numbers in heterogeneous catalytic systems, improved hazardous waste treatment processes, and improved solubilities.

3.The application of ultrasound can accelerate chemical transformation, affect product distribution, initiate free radical formation and polymerization, induce mechanical cleavage of polymers, increase catalytic activity of metal particles by factors as large as 105. The sonification of organic solutions of metal carbonyls leads to the formation of micro- to nano-particles of metals, alloys, oxides, semiconductors. Applications in organic fine synthesis are numerous, especially in reactions via free radicals. Polymer science also has a strong interest in this field.

A very important new domain is the use of ultrasound for the destruction of organic material in industrial waste water. Toxic pollutants which resist to other treatments are destroyed by ultrasound. Environmental chemistry constitutes a very active domain where European workers are in a strong position despite active competition from other countries. Research on the scaling up is performed at universities and by companies. Batch processes on several hundreds of kilograms are known, and new flow-through equipment is being commercialized.

4.The application of microwave heating can accelerate chemical transformations in solution as well as in the solid state, lead to products in a short time with high purity and yields. The aim is to search for a specific microwave effect and to scale up the reactions. The choice of the solvent controls the energy transfer. Moreover, it is not always necessary to work in presence of a solvent, and this aspect is of particular interest to industry.

5.The application of pulse-plasma-discharges offers new possibilities for the synthesis of new materials, the treatment of hazardous and toxic waste, and the acceleration of radical-induced chemical transformations.

6.The application of a combination of the extreme and non-classical conditions mentioned above can lead to synergistic effects, such that the overall effect is more than the sum of the individual effects. The combination of innovative methods and techniques is a new challenge that can lead to unexpected advances in chemical processing techniques.

7.In all mentioned objectives the suggested interaction between engineers, chemists and physicists will be essential in order to scale-up laboratory reactors for practical application in industry.

8.It is also planned to especially collaborate with medium-size industry that can produce appropriate instrumentation to make the extreme and non-classical techniques available to more research groups in all areas of chemistry.

C. Scientific Programme

The scientific programme will depend on the projects submitted by individual research teams. The successful projects will be selected according to the objectives outlined above. At this stage there is no specific scientific programme suggested for this action in order to place no limitations on the invited proposals. The selection will strictly occur according to the outlined objectives.

D. Organization and Timetable

D1.Organization

Research projects fitting in the sub-topics described in section C will be submitted by scientists to the Management Committee members. This Committee will establish contacts between scientists. The organizational structure can be illustrated as follows:

Technical Committee for Chemistry

Management Committee Secretariat

Projects 1 Projects 2 Projects 3 Projects 4 Projects 5 etc.

The Management Committee has responsibilities for :

1.Drawing up the inventory during the first year, organization of workshops and start of the activity; existing contacts will be used which should greatly facilitate this task.

2.The coordination of the joint activities with other COST Actions, joint meetings are likely to result from this activity.

3.Exploration of wider participation and exchange of information with EC-specific programmes, ESF, etc.

4.The planning of the intermediate report, the final report, and the concluding symposium.

Progress in each of the projects will also be reported by the respective participants in their own countries within the framework of existing programmes.

D2.Reports

The progress of the programme will be monitored by brief annual reports from each of the participating scientists which will describe the results of research obtained through concertation. A mile-stone report will be prepared by the Management Committee after 3 years of joint activities. The report will be presented to the COST Technical Committee for Chemistry for their review.

A final report will be published to inform non-participating scientists and research workers interested in the results about the scientific achievements of the Action. It is expected that some reviews by participants which describe the progress made and state of the field will be published in International Journals. To conclude the COST Action, a symposium will be held after 5 years which will be accessible to other scientists.

D3.Timetable

The Action will have a duration of five years and comprise the following four stages:

Stage 1:After the first meeting of the Management Committee a detailed inventory of on-going research and existing plans of the participating groups to begin joint projects will be made. This will result in a discussion document which will allow further planning to occur.

Stage 2:It will be evident which projects are closely related and would benefit from joint activities. Researchers (and co-workers) will set up (and continue) joint collaborative projects, and exchange their recent research results. It may be appropriate to explore wider collaboration with other European countries during this stage.

Stage 3:An intermediate progress report will be prepared after 3 years for review by the COST Technical Committee for Chemistry and by the COST Senior Officials Committee.

Stage 4:This final phase will begin after 4 years and will involve the evaluation of the results obtained. It may include the organization of a symposium for all the participants and co-workers.

E. Economic Dimensions

During the preparation of this Action, interest in participation was shown by researchers from all COST countries except Luxembourg and Iceland.

The economic dimension of the Action (initial estimate of total costs = personnel + operational + running + commission costs) is: 18,8 MECU.

The human effort in the area of "Innovative methods and techniques for chemical transformations" as described in this document, amounts to 500 man-years, being equivalent to 12,5 MECU approximately.

E1.Personnel costs

Estimates of personnel costs (research + administration) will
depend on the rates applicable for various EU countries (estimation
12,5 MECU + 2 MECU = 14,5 MECU).

E2.Operational and running costs

The estimate of the total operational and running costs including costs of instruments and materials is 4 MECU.

E3.Coordination costs

The costs for coordination to be covered by the COST budget are estimated to be 60 kECU per year, i.e. a total of 300 kECU for the five year duration of the project.

Programma(i)

IC-COST - European cooperation in the field of scientific and technical research (COST), 1971-

Argomento(i)

13 - Chemistry

Invito a presentare proposte

Data not available

Meccanismo di finanziamento

Data not available

Coordinatore

N/A

Contributo UE

Nessun dato

Indirizzo

Costo totale