Sulphated Ash Testing

Sulphated Ash testing involves the precise combustion of a sample under controlled conditions to determine its inorganic content. An accurately weighed sample is first treated with a specified amount of sulfuric acid. The sample is then carefully ignited, initially at a lower temperature to char the organic material, and subsequently at a high temperature (typically between 500°C and 800°C, depending on the sample and standard) in a muffle furnace. The sulfuric acid treatment converts most inorganic impurities into stable sulphates, preventing volatilisation and ensuring that the remaining residue, or sulphated ash, can be accurately weighed after cooling to a constant mass. This method ensures reliable and reproducible results, critical for purity assessment.