Chemical and Biomolecular Engineering Faculty Research


New Method for Monitoring of Adsorption Column Saturation and Regeneration Ii: On-line Measurement

Document Type


Publication Date



A new method suitable for the on-line monitoring of adsorption column saturation/regeneration cycles was developed based on the discovery that the electrical resistance of packed bed adsorbents changes dramatically upon adsorption and returns to its original value upon desorption. This change can be measured reliably and reproducibly. The two systems studied on-line in real time were methyl chloride (MeCl) adsorption on zeolite molecular sieve (HISIV 3000) and water vapour adsorption on basic alumina (RF-200). The sequential change in electrical readings at localized points within the column indicated the movement of the adsorption front, tracking the onset of breakthrough. The electrical readings returned to their original values upon desorption and the results were reproducible. Concurrently with the electrical measurements, the effluent gas of the MeCl/HISIV system was monitored for MeCl using an on-line gas chromatograph. An adsorption isotherm was created using the “length of unused bed” concept. The resistance change of the HISIV was found to be proportional to the square root of the amount of MeCl adsorbed, similarly to the C/CO2 system discovered recently by our group. The universality of this correlation is being investigated. The simple measurement technique introduced here has the potential to improve the operating efficiency of industrial adsorption towers.

Publication Title

Chemical Engineering Science





First Page


Last Page