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  1. Georg-Wilhelm Oetjen

Published Online: 15 JAN 2004

DOI: 10.1002/14356007.h12_h01

Ullmann's Encyclopedia of Industrial Chemistry

Ullmann's Encyclopedia of Industrial Chemistry

How to Cite

Oetjen, G.-W. 2004. Freeze-Drying. Ullmann's Encyclopedia of Industrial Chemistry. .

Author Information

  1. Lübeck, Germany

Publication History

  1. Published Online: 15 JAN 2004

Chemistry Terms

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The article contains sections titled:

1.1.Goals of Industrial Freeze-Drying
1.2.Steps of the freeze-drying process
1.3.Chemical Engineering Tasks in Industrial Freeze-Drying
2.Process Steps
2.2.Main Drying
2.3.Transition from Main to Secondary Drying (SD)
2.4.Secondary Drying
2.5.Packing and Storage
3.Temperatures and Pressures
3.1.Barometric Temperature Measurement
3.2.Pressure During Secondary Drying
3.3.Water-Vapor Flow
3.4.Residual Moisture Content
3.5.Uniformity of Temperatures, Pressures, and Product
4.Structures of Frozen and Dried Products
4.1.Influence of Freezing Method and Excipients
4.2.Methods of Structure Analysis
5.Industrial Freezing and Freeze-drying Installations
5.1.For Pharmaceutical Products
5.2.Regulatory Requirements for Pharmaceutical Plants
5.3.Food Plants
5.4.Process Automation
5.4.1.Prerequisites for Process and Plant Automation
5.4.2.Control of the Process and the Plant by Thermodynamic Data Measured During the Process: Thermodynamic Lyophilization Control
5.4.3.Transfer of Pilot Plant Data to Production
6.Some Examples of Freeze-drying Processes
6.1.For Pharmaceuticals
6.1.1.Process Reproducibility
6.1.2.Shorter Drying Cycle
6.1.3.Selection of Exipients
6.2.For Food
6.3.For Metal Oxides, Ceramic Powders
7.Economic and Social Aspects, Outlook