Ashing is the process of removing organic material from a sample before analysis and is widely used in the food and petroleum industries. The processes of ashing can generally be split into two categories: wet ashing and dry ashing.

Wet ashing removes organic material from a sample employing a liquid phase reactant such as combinations of acids. Dry ashing is achieved through the controlled combustion of a sample in air. Generally, dry ashing procedures follow the same basic principle: samples should be sufficiently heated in air which causes oxidation and removal of organic material from the sample.

The remaining material is the ash and this contains the incombustible compounds from the sample. The residual ash following the incineration of coal or coke in air is derived from inorganic complexes in the original coal substance and from related mineral matter. This means that the result of the determination is “ash” and not “ash content” as coal does not contain any ash.

Importance of Ashing

The calculation of proportional mass of ash following combustion is useful in itself. For example, in the petroleum industry incombustible components in fuels need to be minimized so analysis of ash content is critical.

Ashing can also be used to analyze soil samples. A comparison of the mass before and after ashing shows the total organic proportion of the soil.

In the food industry ashing is used to analyze the mineral content in foodstuffs.

What are ISO Standards?

ISO standards are the collective and refined wisdom of those with expertise in subject matter such as manufacturers, sellers, buyers, trade associations and regulators. Quality management is important to work more efficiently and reduce failure.

The International Organization for Standardization (ISO) is an independent, non-governmental agency meaning they can act without being hindered by outside associations. This enables ISO to apply fair and impartial judgement in all standardized testing issues. An ISO standard has become a highly sought-after accolade as it proves authenticity.

ISO 1171 for Ashing

Ashing is often used as a process in the beginning of the analysis of inorganics in organic samples  such as petroleum, plastic and biological samples. Ashing of plastic waste on a large-scale can be used to remove harmful chemicals like toxic metals in order for them to be safely removed. Ashing tests of coal and coke are defined within standard test method ISO 1171.

ISO 1171 Adherent Ashing Tests at Thermcraft

During ashing, complete combustion of a sample is critical to gain accurate results. For this reason a purpose-built ashing furnace must be employed. As there are many different ashing applications it is important to consider whether a furnace will only be usable for a specific process or if it will also be available for use in general heat treatment applications. Ashing applications should, in most cases, adhere to ISO 1171 standards.

Thermcraft works hard to ensure that our extreme heat-emitting equipment, and furnaces in particularly are, rigorously standardized and adherent with ISO 1171. The ISO 1171 standardization gives us expertise to be confident in the caliber and versatility of our furnaces.

To find out more about our ISO 1171 adherent furnaces please contact our team.