Simultaneous adsorption of Cd2+ ions and cationic dye from water by adsorption on sepiolite,

Abstract

Otpadne vode tekstilne industrije, pored boja, sadrze cesto i jone metala kao posledicu obrade i oplemenjivanja tekstilnih materijala, sto utice na zagadenje prirodnih voda. Pokazano je da je adsorpcija na prirodnim mineralima efikasan i ekonomican postupak za uklanjanje mnogih boja, kao i za uklanjanje katjona teskih metala, a u poslednje vreme se ispituje mogucnost simultanog uklanjanja boja i katjona metala na razlicitim glinenim mineralima. U ovom radu je ispitivano simultano uklanjanje katjonske boje Basic Yellow 28 i Cd2+ jona na prirodnom glinenom mineralu sepiolitu. Utvrdeno je da povecanje pH vrednosti ne utice na kolicinu adsorbovane boje, dok u slucaju Cd2+ jona adsorpcioni kapacitet raste sa porastom pH. Pokazano je da povecanje koncentracije boje ne dovodi do smanjenja ko­ licine adsorbovanih Cd2+ jona, kao i da povecanje koncentracije Cd2+ jona ne uzrokuje smanjenje kolicine adsorbovane boje.

Wastewaters of textile industry contain dyes and metal ions as a result of processing and finishing of textile materials which affects the pollution of natural waters. The adsorption on natural minerals is effective and economic method for the removal of both dyes and metal ions. Recently, the possibility of simultaneous removal of dyes and metal cations onto clay minerals has been investigated. In this study, simultaneous adsorption of dye Basic Yellow 28 and Cd2+ ions on natural sepiolite was investigated. lt was shown that increase of pH value had no influence on the adsorption capacity for dye, while the adsorption capacity for Cd2+ ions increased with pH increasing. The increase of dye concentration did not decrease the quantity of adsorbed Cd2+ ions and the increase of Cd2+ ions concentration did not decrease the quantity of adsorbed dye.