technical chemistry
The Technical Chemistry deals with the transfer of chemical reactions and processes in technical procedures and the optimization of existing processes and procedures from an economic and ecological point of view.
Research and teaching focus on catalyst and process development , mechanical and thermal basic operations, process science and chemical reaction engineering .
history
The first beginnings of technical chemistry can be found in the seventeenth century through the work of Johann Rudolph Glauber on the production of acids and salts . Glauber produced concentrated hydrochloric acid and nitric acid and discovered the Glauber's salt named after him around 1625 . A high point in technical chemistry in the eighteenth century was the development of the lead chamber process by John Roebuck . The first lead chamber process was put into operation in England as early as 1746. The process was further developed several times, particularly by Joseph Louis Gay-Lussac , who introduced the so-called Gay-Lussac tower for the recovery of nitrogen oxides in 1827, as well as the step of nitrogen oxide reoxidation by atmospheric oxygen in the Glover tower introduced by John Glover in 1859 .
Knowledge of technical chemistry was summarized in textbooks early on. This is how Johann Friedrich Gmelin defined technical chemistry in his handbook of technical chemistry in 1795 :
"Technical chemistry is that part of applied chemistry which teaches the chemical principles of factories, manufactories, arts and craftsmen, and their beneficial application to them."
The history of technical chemistry in the true sense is linked to the development of the chemical industry as an economic branch. With the development of aniline dyes by August Wilhelm Hofmann , it experienced a tremendous boom, especially in Germany. From 1859, many paint factories were founded in Germany within a few years, such as Boehringer Mannheim , Bayer-Werke , Hoechst , Badische Anilin- und Soda-Fabrik (BASF), Agfa , Schering and Boehringer Ingelheim .
In order to bridge the discrepancy between the demands of industry on graduates and university education, more institutes for technical chemistry were founded at the end of the nineteenth century on the initiative of the German Chemical Society and Carl Duisberg .
A milestone in technical chemistry at the beginning of the 20th century was the ammonia synthesis according to Haber and Bosch. Fritz Haber was appointed associate professor for technical chemistry at the University of Karlsruhe in 1898 , and from 1904 he dealt with the production of ammonia from the elements. The development of the Haber-Bosch process posed a challenge to chemistry and process engineering in many respects. Reactors had to be developed that could withstand pressures of up to 300 bar and temperatures of up to 500 ° C , and catalysts that could economic yield of ammonia allowed.
In the twenties and thirties of the twentieth century, carbon and acetylene chemistry were the dominant topics in technical chemistry.
The availability of inexpensive crude oil after 1950 and thus also of ethylene led to an unprecedented expansion of industrial chemical production and thus to ever newer developments in technical chemistry. A milestone of this time is the development of the low-pressure process for polyethylene production by Karl Ziegler .
| year | Explorer | Discovery / achievement |
|---|---|---|
| 1625 | Johann Rudolph Glauber | Process for the production of nitric acid , hydrochloric acid and sodium sulfate |
| 1746 | John Roebuck | Lead chamber process for the production of sulfuric acid |
| 1827 | Otto Linné Erdmann | First journal for technical and economic chemistry |
| 1839 | Charles Goodyear | Vulcanization of rubber |
| 1840 | Justus von Liebig | Fertilizers , rationale of agrochemistry |
| 1894 | Wilhelm Ostwald | Modern definition of catalysis |
| 1909 | Fritz Haber , Carl Bosch | Ammonia synthesis |
| 1909 | Fritz Hofmann | Synthetic rubber |
| 1913 | Friedrich Bergius | Carbohydrate hydrogenation using the Bergius method |
| 1925 | Franz Fischer , Hans Tropsch | Fischer-Tropsch synthesis |
| 1928 | Walter Reppe | Acetylene chemistry , e.g. B. Hydrocarboxylation |
| 1938 | Otto Roelen | Hydroformylation |
| 1953 | Karl Ziegler | Polyethylene using the low pressure process |
Basics
Chemical reactions cannot simply be transferred to large-scale industrial production. Technical chemistry is therefore concerned with the question of how many tons of the same product can be produced in a factory while minimizing production costs. This is done empirically or by a mathematical optimization based on a model description of the reaction process and the reactor. Almost every chemical production can be divided into three steps:
First the starting materials are prepared, in the second step the actual reaction takes place. In the last step, the reaction mixture is finally prepared. Chemical process engineering is concerned with preparation and processing, chemical reaction engineering with reactions on a technical scale. Transport, heat and time balances must be drawn up for the necessary calculations. Dimensionless key figures ( Euler number , Reynolds number , Nusselt number , Damköhler number ) are often used to facilitate the scale-up .
Technical chemistry enables the efficient production of basic , intermediate and end products. Between 1970 and 1980, improvements in chemical processes made it possible to reduce the energy required for chemical reactions by around 40% while maintaining the same production volume.
Chemical process science
An important aspect of technical chemistry is the understanding of the material combination of industrial organic and inorganic chemistry. The basic chemicals are initially created from the organic raw materials crude oil, coal and renewable raw materials. A large number of intermediate and end products are made from this.
Chemical process science continues to examine the processes and reaction procedures of the most important industrial chemical products.
Starting with the raw materials crude oil , natural gas , coal and increasingly renewable raw materials , basic chemical products such as olefins and aromatics are first manufactured.
These are processed into intermediate products such as alcohols , phenols , aldehydes , ketones , carboxylic acids or amines .
The end products of the chemical industry such as polymers , detergents , pesticides , pharmaceuticals and dyes are made from the basic and intermediate products.
The raw materials of industrial inorganic chemistry include air , sulfur , sodium chloride , coke and water , from which the end products such as acids, alkalis, fertilizers, glass, pigments, catalysts and materials can be produced via a few intermediate stages such as ammonia and chlorine .
The task of technical chemistry is to determine the most economical process routes from the available synthetic routes depending on the availability of the raw materials and taking into account the energy consumption.
Chemical processes differ in the type of chemical reaction carried out, for example chlorination , hydrogenation , nitration , oxidation , polymerization or sulfonation . The energy can be supplied in various ways, for example thermally, electrochemically or photochemically .
If both types of reaction are possible, the technical conditions and the economic aspects can influence the decision as to whether a process is carried out continuously or discontinuously as a batch process. Continuous systems are suitable for a product that is produced in large quantities, while a batch process often allows greater flexibility in product variation, but at the expense of the quantity produced.
Further classification features for chemical processes are the number of stages carried out (single / multi-stage), the heat release (endo / exothermic) and the type of catalysis used (homogeneous / heterogeneous / biocatalytic).
catalysis
Catalysis research is of particular importance within technical chemistry, as around 80% of all chemical products go through a catalytic process in the course of their manufacture.
In the manufacture of basic and intermediate products, heterogeneous catalysis plays by far the greatest role; in the manufacture of intermediate and end products, the importance of homogeneous and biocatalytic processes is increasing.
Based on the results of basic research , attempts are increasingly being made to place catalyst and process development on a knowledge-oriented basis.
Basic operations
The physical processes of a process that are necessary in addition to the chemical reactions are called mechanical and thermal basic operations. Basic operations are the elementary steps in performing a procedure.
These are used to prepare raw materials, for example by crushing, mixing the reactants and conveying and processing the products using separation processes.
Basic mechanical operations
The important mechanical basic operations include the process for combining materials, conveying and shaping, the separation process and the comminution process for solids.
The methods used for combining substances include emulsifying , kneading, mixing , pelleting , pressing , stirring , suspending , blending and spraying. One of the most important methods of conveyance is pumping .
Mechanical separation processes are used, among other things, to separate solids from liquids and gases or liquids from gases. Known separation methods for the separation are the decantation , the electrodeposition , the filtration , the flotation , the sedimentation , the views , the screening , the sorting and the centrifugation .
Comminution processes are mostly used to set certain grain size distributions or to enlarge the surface, for example to make a chemical reaction run faster. The methods frequently used here include breaking , grinding , grinding, tearing and cutting up .
Basic thermal operations
Substances can be separated or combined through basic thermal operations. The following basic thermal operations are distinguished according to the type of phases occurring:
- Gas-liquid: rectification , absorption
- Liquid-liquid: Liquid-liquid extraction
- Solid-liquid: crystallization
- Gas-solid: adsorption
By far the most frequently used method for material separation is rectification, which can be carried out in a single stage as distillation or in several stages in a continuous or discontinuous process. In the past, rectification columns were often designed using the McCabe-Thiele graphic method .
Chemical reaction engineering
- → Main article: Chemical reaction engineering
Chemical reaction engineering deals with the design of chemical reactors under given reaction conditions such as pressure and temperature, the material and energy balance and the macrokinetics of a reaction with the aim of minimizing the investment and operating costs of a reactor with optimal throughput.
Examples of the basic types of chemical reactors are the tubular reactor , the stirred tank and the continuous stirred tank . The residence time behavior is an important parameter of these types of reactor . Simplified mathematical models of these types of reactors are called ideal reactors .
Recent developments
The more recent developments in technical chemistry are characterized by the increasing pressure on the economic efficiency and environmental friendliness of the processes as well as the increasingly scarce supplies of the most important raw materials, especially crude oil. The Technical Chemistry trend report published by the GDCh provides an overview of the most important trends . Examples of more recent developments are the use of biomass as a chemical raw material, microreaction technology and the use of novel solvents.
- Sustainable chemistry: Above all, the use of biomass as a chemical raw material is being investigated. The main research areas are the selection and processing of renewable raw materials, their subsequent chemistry and the interfaces to biotechnology .
- Microreaction technology : Microreaction technology uses components to carry out chemical reactions with particle sizes in the millimeter to centimeter range. The aim of the investigations is the development of microreactors and the study of chemical reactions under microreaction conditions, since here normally no problems with mixing, diffusion or heat transfer occur.
- Novel solvents: When carrying out homogeneous catalytic processes, the recovery of the catalyst and the separation of the products from the solvent are often decisive for the economic viability of a process. Attempts are made to carry out reactions in supercritical solvents , ionic liquids or in water. The ionic liquids are salts that become liquid at room temperature or slightly above. By choosing suitable cation / anion pairs , the properties of these liquids can be set in a targeted manner over a wide range. Due to their ionic nature, they are hardly volatile and have properties that differ greatly from conventional organic solvents. Water as a solvent often offers the advantage that the organic product formed in a homogeneous catalytic reaction does not mix with water and therefore allows easy separation. The use of hyperbranched polymers is also being investigated.
Teaching and Research
The DECHEMA has a teaching program Technical Chemistry worked as a guide for university education, which is implemented in most universities and technical colleges.
literature
General textbooks
- M. Baerns , A. Behr , A. Brehm, J. Gmehling , H. Hofmann , U. Onken, A. Renken: Technische Chemie , Wiley-VCH 2006, ISBN 3-527-31094-0 .
- HG Vogel: Textbook Chemical Technology , Wiley-VCH 2004, ISBN 3-527-31094-0 .
- HG Vogel: Process Development , Wiley-VCH 2002, ISBN 3-527-28721-3 .
- M. Jakubith: Basic operations and chemical reaction engineering - An introduction to technical chemistry , Wiley-VCH, 2002, ISBN 3-527-28870-8 .
- G. Emig , E. Klemm: Technical chemistry: Introduction to chemical reaction technology , 568 pages, Verlag Springer, 2005, ISBN 978-3-540-23452-4 .
Special subject areas
- M. Wächter: substances, particles, reactions . Verlag Handwerk und Technik, Hamburg 2000, ISBN 3-582-01235-2 .
- J. Hagen: Chemical reaction technology - An introduction with exercises , VCH-Verlag, Weinheim, 1992.
- K. Dialer, U. Onken, K. Leschonski : Basic features of process engineering and reaction engineering , Hanser-Verlag, Munich, 1984.
- O. Levenspiel : The Chemical Reactor Omnibook , Osu-Verlag, Oregon, 1993.
- HJ Arpe: Industrial Organic Chemistry , Wiley-VCH, ISBN 3-527-30578-5 .
- Collective of authors: Textbook of chemical process engineering , VEB Deutscher Verlag für Grundstoffindindustrie, Leipzig 1980
- R. Turton, RC Bailie, WB Whiting and JS Shaeiwitz: Analysis, Synthesis, and Design of Chemical Processes , Prentice Hall, 2002, ISBN 0-13-064792-6 .
reference books
- E. Bartholome, E. Biekert, H. Hellmann, Ullmanns Encyklopadie der Technischen Chemie , 25 volumes, Wiley-VCH, 1984, ISBN 3-527-20000-2 .
- R. Dittmeyer, W. Keim , G. Kreysa , K. Winnacker , L. Küchler, Winnacker-Küchler: Chemical Technology: Methodical Basics: Chemical Technology: Vol. 1 , 919 pages, Wiley-VCH, ISBN 978-3-527 -30767-8 .
- RE Kirk and DF Othmer: Kirk-Othmer Encyclopedia of Chemical Technology , Wiley-Interscience, 2001, ISBN 0-471-41961-3 .
Magazines
- Chemical engineer technology , WILEY-VCH Verlag GmbH & Co. KGaA.
- Industrial and Engineering Chemistry, published by the American Chemical Society , Washington, DC.
- Chemical Engineering Science, Elsevier BV
Special subject areas
- Advanced Materials , Wiley-VCH Verlag, Weinheim.
- Reaction Kinetics and Catalysis Letters, Springer Science & Business Media BV
Web links
- www.lectures4you.de - Compilation of freely accessible teaching offers on technical chemistry on the Internet.
Individual evidence
- ^ H. Ost: Textbook of Technical Chemistry , published by Robert Oppenheim, Berlin, 1890, p. 53.
- ↑ Erich Pietsch: Glauber, Johann Rudolph. In: New German Biography (NDB). Volume 6, Duncker & Humblot, Berlin 1964, ISBN 3-428-00187-7 , p. 437 f. ( Digitized version ).
- ↑ Inorganic Chemistry , by Erwin Riedel, Christoph Janiak.
- ↑ Handbook of Technical Chemistry, Volume 1 , by Johann Friedrich Gmelin, 1795.
- ↑ Chronicle of the City of Mannheim - Milestones of the 19th Century .
- ^ Bayer AG Bayer company history: The early years (1863–1881) .
- ↑ The Industriepark Höchst - a success story ( Memento of the original from July 8, 2010 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. .
- ↑ 1865–1901: The emergence of the chemical industry and the age of colors ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. .
- ^ The Early Years 1867: AGFA, it all began with color ( Memento of November 3, 2010 in the Internet Archive ).
- ^ Schering AG, Wedding .
- ↑ 1885–1948: Innovative Beginnings ( Memento of the original of October 12, 2010 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. .
- ↑ Chemical-Geoscientific Faculty of the Friedrich Schiller University Jena: History of the Institute ( Memento from May 30, 2011 in the Internet Archive )
- ↑ The long way to carbon chemistry: gasoline from Böhlen - an (almost) never-ending story .
- ^ Nobel Prize lecture by Karl Ziegler (PDF; 633 kB).
- ↑ K.-H. Reichert: Fundamentals of technical chemistry I, reaction technology, lecture notes of the TU Berlin from 1982, pp. 132-133.
- ^ Scientific Background on the Nobel Prize in Chemistry 2007, Chemical Processes on Solid Surfaces Gerhard Ertl .
- ^ GDCh: Trend Report Technical Chemistry ( Memento of October 12, 2004 in the Internet Archive ).
- ↑ Report on sustainable chemistry in the innovation report .
- ^ Report of the Fraunhofer Institute .
- ^ Ionic liquids as a new material class, report in the Biotech-LifeScience Portal Baden-Württemberg ( Memento from March 10, 2014 in the Internet Archive ).
- ↑ Article about Hyperbranched Polymers ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (PDF; 105 kB).
- ↑ Report on Hyprebranched Polymers in the Innovation Report .
- ↑ Course profile technical chemistry at DECHEMA (PDF; 172 kB).
