Dynamics of the process of colour adsorption from waste waters after dyeing textile fibres on natural zeolites

Hemijska Industrija

关键词: waste waters;    natural zeolite;    adsorption;    colour adsorption;    textile dyes;   

DOI  :  10.2298/HEMIND120209049C

来源: DOAJ

【 摘 要 】

This study analyses the process of purifying waste waters from textile fibredyeing by adsorption of colour on natural zeolites from “Nemetali” mine,Vranjska Banja, Serbia. The process has been analyzed in an adsorptioncolumn filled with natural zeolite as the adsorbent. Adsorbents are organicsubstances, i.e. colour residues from waste waters, left after textilefibres dyeing. The concentration change in waste waters is represented withthe parameter of chemical oxygen demand (COD). Two models of diffusion havebeen considered: diffusion in pores and diffusion in adsorbent phase onsolid adsorbent, for different input loads and two zeolite granulations (13and 35 mm). It was found that the diffusion in zeolite pores that were inadsorbed phase is dominant in this case, which can be explained by largedimensions of used colours’ molecules. This is the reason why its adsorptionin zeolite micro pores is minimal, and yet it diffuse well in alreadyadsorbed phase on solid adsorbents. Since this process is slower, it willdetermine the overall rate of colour adsorption from waste waters. Specificequilibrium capacity, specific dynamic capacity, as well as the level ofadsorbent utilization were determined by the use of mass transfer zoneconcept. It has been shown that the adsorption of organic substances fromwaste waters is satisfactory, and is around 80%. The highest degree ofadsorbent utilization is obtained at the lowest flow of 0.167 cm3 s-1, whilethe lowest degree of utilization of 30%, is obtained at the highest flow of3.27 cm3 s-1. Input load has significant influence on the degree of columnutilization, while higher values of COD0 result in lower degrees of columnutilization. Key words: waste waters, natural zeolite, adsorption, colouradsorption, textile dyes

【 授权许可】

Unknown