Characterization of humidity conditioning ceramics by B-value method

To characterize humidity conditioning ceramics, the relative humidity as a function of temperature (H(T)) was measured using a glass desiccator technique with varying the ambient temperature between 298 and 288 K, A logarithmic plot of H(T) was approximately represented by a linear function, and the humidity conditioning ability was evaluated by the slope (B) of such a linear equation (B-value method), Humidity conditioning ceramics, made of several ceramic materials such as Wakkanai diatomaceous shale, calcium silicate and zeolite, were characterized according to their B-values in comparison with wood, The relation between the B-value and the ratio of the exposed surface area of the material to the volume of desiccator was also investigated to extend the efficiency of the B-value method to the large scale of actual applications, It was also found that the B-value method to estimate the humidity conditioning ability for wooden material can be applied to porous ceramics, which had B-values higher than wood, The porous diatomaceous ceramics showed the highest B-value among the ceramic investigates.