Feasibility of Using Combustion-Titrimetric Apparatus and Procedure to Determine Sulfate Content in Portland Cements

摘要

Feasibility of using a combustion-titrimetric apparatus and procedure to determine sulfate content in hydraulic cements was investigated. The apparatus consisted of an induction furnace and an automatic titrator. A number of procedural and instrumental variables were investigated using statistically designed experiments. It was found that a blank determination is necessary only when a new supply of crucibles, crucible covers, and accelerators is used. For routine work, as opposed to highly precise work, it is recommended that an F value factor be determined once a week and when new solutions are made, when sample and accelerator weights are changed, or when any change is made in the operation of the furnace or in heating time. The investigation indicated that the procedure was relatively easy to follow and that a single determination could be made by use of the automatic titrator in 10 min. The precision of the procedure was determined to be 0.030% of sulfur trioxide (SO3), which is equivalent to the precision obtained with the referee gravimetric procedure that is presently in general use. (Author)