TAPPI T 247 : CM 83

Is for the volumetric analysis by ethylene diamine tetraacetic acid (EDTA) titration of traces of acid soluble calcium in ashed pulp. Alternative methods for calcium which are less time consuming are flame photometric methods and particularly use of the atomic absorption spectrophotometer. Typically this determination is made on the filtrate from the acid insoluble ash as determined in TAPPI T 224 "Acid Insoluble Ash in Pulp". Any calcium present as calcium silicate in the acid insoluble material will be be determined.