title: Studies on the pretreatment of zeolite clinoptilolite in packed beds.
abstract: The effect of volumetric flow rate, ranging from 5 to 45 Bed Volumes per hour (BV h(-1)) and temperature, ranging from 25 to 59 degrees C, during pretreatment of clinoptilolite on its effective capacity has been investigated. Pretreatment tests have been performed in an upflow ion exchange bed. Increased temperatures were found to increase the effective capacity of clinoptilolite. Effective capacity was maximal at low volumetric flow rates, indicating an influence of contact time and complete saturation of the zeolite bed at flow rates lower than 10 BV h(-1). Furthermore, a comparison between upflow and downflow operation at the same operating conditions showed that better results are obtained in upflow conditions, probably due to the better wetting of the material and the absence of liquid maldistribution.
authors.affiliation: Department of Chemical Engineering, National Technical University of Athens, Zografou Campus, 157 80 Athens, Greece.
authors.forename: V J
authors.initials: VJ
authors.lastname: Inglezakis
authors.forename: M D
authors.initials: MD
authors.lastname: Loizidou
authors.forename: H P
authors.initials: HP
authors.lastname: Grigoropoulou
mesh_terms: D007474:Ion Exchange; D013696:Temperature; D014872:Water Movements; D014873:Water Pollutants / Q000302:isolation & purification*; D017641:Zeolites / Q000737:chemistry*
chemical_list: D014873:Water Pollutants; C083175:clinoptilolite; D017641:Zeolites