Drying and Dehydration

The ultimate hydration state of a material may influence several physicochemical properties including physical and chemical stability. The hydration state of crystalline substances is of particular concern in the pharmaceutical industry. For instance, some hydrated materials become amorphous upon dehydration. Also, different hydrate forms can affect the material solubility, dissolution rate, flowability, and compressibility. These factors affect the entire chain of the drug development process from preformulation to solid form development to packaging and storage.

Application Note 36: Investigation of Hydrate Formation and Loss Using DVS | Request a copy

Application Note 59: Investigation of Channel Hydrate Formation and Loss Using the DVS | Request a copy

Application Note 501:Environmental Microscopy using the GenRH-A Humidity Generator and Mcell Accessory

The moisture sorption properties of foods are critical for their shelf-life stability. This is especially true for materials for crackers and noodles which are vulnerable to either temperature or humidity shocks, and in many some cases, excess water uptake will lead to poor texture, dissolution, caking or even mould growth. Food products can take up a such a high amount of water, that they can melt and collapse thus rendering them unsalable.

Application Note 03: Polymorphism in Spray Dried Lactose | Request a copy

Application Note 503: Investigating Dried Milk Powders Using Optical Microscopy at Different Humidity Conditions
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Water content is one of the most important parameters controlling the condition of skin and hair fibres. Under ambient conditions human hair can take up as much as 35% by weight of water before being completely wet. Bleaching and exposure to temperature as well as light would damage the inner structure of the hair and cause detectable changes in the moisture uptake properties. Therefore, the determination of equilibrium water contents, water sorption isotherms and hysteresis is of fundamental interest for the hair condition as well as for skin cream formulations.

Application Note 29: Moisture Desorption of Creams and Calculations | Request a copy

Application Note 52: Vapor Permeability of Porous Materials using Payne Diffusion Cell | Request a copy

Proton Exchange Membrane Fuel Cells (PEMFC) are an expanding area of research for use as low pollution power generators for mobile and stationary applications. The PEMFC is composed of a membrane electrode assembly consisting of several layers. There are typically two carbon cloth gas-diffusion layers that allow concurrent transport of gases and water while collecting current and two carbon-supported Pt based catalyst layers where the electrochemical reactions take places. These layers are sandwiched between a proton exchange membrane that permits proton transfer from anode to cathode.

Application Note 39: Measuring Moisture Sorption and Diffusion Kinetics on Proton Exchange Membranes Using the DVS
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Microporous materials like Metal Organic Frameworks (MOFs) and zeolites have been a novel class of candidates for absorbents, catalysts and separation processes. For example, a highly flexible micro-porous metal organic framework material exhibits remarkable capability to capture and separate carbon dioxide from other small gases, including N₂, H₂, CH₄, CO and O₂.

Application Note 51: Gas Capture and Vapor Separation by Microporous Materials | Request a copy

Application Note 504: Water Vapor Induced Mesoporous Structure Collapse Observed by GenRH with Mcell and FT-IR
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Activated carbons are widely used throughout industry in a variety of applications from environmental air filtration to solvent and heavy metal recovery. The sorption of moisture by activated carbons is pertinent to many of these applications.

Application Note 14: Moisture Sorption of Activated Carbon | Request a copy

The moisture sorption properties of tobacco are critical for the characterisation of their drying and shelf life stability. Tobacco is vulnerable to both temperature and humidity shocks which can occur during transport. Once tobacco becomes wet, it can lose taste, any added flavour or even its combustibility. Problems can also occur with very dry tobacco, which can become too fragile to be used in manufacture.

Application Note 21: Moisture Sorption on Tobacco of Various Origins | Request a copy

Biomaterials include biomass materials such as wheat straw which is an abundant and inexpensive natural biopolymer. Bio-fuel has been attracting attention due to the future potential shortages of fossil fuel. One of the crucial steps of producing bio-ethanol from wheat straw is its pre-treatment prior to drying which should facilitate the economic feasibility and yield efficient conversion into biofuel. Also, paper and most related cellulosic materials exhibit substantial moisture take up. Dynamic Vapour Sorption (DVS) was used to assess the drying and moisture uptake of both wheat straw and cellulosic materials.

Application Note 02: moisture Sorption of EC Standard Reference Material RM 302 on a DVS-1 Instrument

Application Note 57: Characterization of Wheat Straw for Bio-fuel Application

Application Note 505: Identifying Structural Changes in the Protein Collagen Using Humidity Generation and FT-IR
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An important factor in the long-term storage stability of cements is the rate at which moisture is taken up by the cements under specific storage conditions. Traditionally this is done by storing large containers of cement under controlled conditions and periodically weighing over many months or even years. Here we measure the moisture sorption kinetics of two different cements using Dynamic Vapour Sorption (DVS) methodology as a well as a range of building materials.

Application Note 09: Measuring the Moisture Sorption of Kinetics of Cements using DVS | Request a copy

Application Note 104: Vapor Sorption Properties of Building Materials using Gravimetric Sorption Instrumentation – an Overview