Zero-length-column (ZLC) technique is used for estimating intraparticle diffusivity, but no algorithm is available for producing reliable accuracy estimation. To tackle this issue, this paper presents a non-fitting algorithm for explaining ZLC experimental data. Compared with conventional methods that fit ZLC data to a diffusion model, the non-fitting method replaces the curve-fitting problem with an algebraic-equation solving problem. The new method is validated by using two independently reported ZLC data sets. The non-fitting approach can provide from one experimental run multiple parameter estimates, a set of estimates that contain the information of experimental error distribution. From the distribution, important statistics such as variance, standard deviation, and confidence interval can be derived, thus providing a direct way of determining the accuracy of parameter estimation.

Adsorption,mass diffusivity,zero-length-column,paramter estimation