A pseudo first order rate model for the adsorption of an organic adsorbate in aqueous solution

✍ Scribed by Pam H Y Li; Roderick L Bruce; Malcolm D Hobday

• Publisher: Wiley (John Wiley & Sons)
• Year: 1999
• Tongue: English
• Weight: 136 KB
• Volume: 74
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/(sici)1097-4660(199901)74:1<55::aid-jctb984>3.0.co;2-d

✦ Synopsis

Five low rank, coal-based adsorbents, i.e. coal, grus, two chars, and an activated carbon were used to adsorb a low molecular weight organic compound from aqueous solution. The rates of adsorption were found to conform to pseudo ürst order kinetics with good correlation (r2 greater than 0.996). This kinetic model was used to calculate pseudo ürst order rate constants min-1) and rela-(k 1 º tive rate constants (rate constant/unit mass of adsorbent, for the adsorption process. k 1

/ min-1 g-1)

Rate properties have been explained in terms of both a diþ usion and chemically controlled rate determining step. Rate constants for the üve adsorbents vary as expected on the basis of their physical properties, that is slowest for grus (compressed coal) and fastest for the activated carbon.