Use Of An Alternative Adsorbent Of An Organo-Modified Nanoclay For The Removal Of Cr(VI) From Wastewater

Abstract

In this study, the performance of organo-modified nanoclay for the removal of Cr(VI) ions from aqueous solutions was evaluated. If organoclays can adsorp heavy metals at a variety of environmental pH values, they could be effective adsorbents for mixed-waste systems containing relatively nonpolar organic pollutants and heavy metals. The present work deals with the adsorption of Cr(VI) ions on organo-montmorillonite nanoclay which is modified with octadecylammonium, I30E, and procured from Nanomer, Nanocor, Inc., IL, USA. The sorption of Cr(VI) on organoclay was investigated in a batch arrangement. The influence of contact time, solution pH, and initial metal concentration and amount of adsorbent on the removal of Cr(VI) ions was studied. The amount of Cr(VI) ions left after adsorption process was determined by UV-Visible Spectrophotometer. The Cr(VI) ions adsorption capacity of organoclay showed a maximum at pH= 2 and diminished with increasing pH from 2 to 6. The applicability of the Langmuir and Freundlich adsorption isotherms was tested. The research of adsorption isotherm demonstrated that, adsorption reactions of organoclay belonged to Langmuir model.

Keywords

• Organoclay
• Adsorption
• Cr(VI)

ORGANO-MODİFİYE NANOKİLİN ALTERNATİF BİR ADSORBAN OLARAK ATIKSULARDAN Cr(VI) UZAKLAŞTIRILMASINDA KULLANIMI

Öz

Bu çalışmada, organo-modifiyeli nanokilin sulardan Cr(VI) iyonlarının giderimindeki performansı değerlendirilmiştir. Organokillerin değişik pH aralığında ağır metalleri giderebildiği bilindiğinden, hem apolar organik kirleticiler hem de ağır metaller içeren karışık atık su sistemlerinde de etkili olabilecekleri düşünülmüştür. Bu amaçla, oktadesilamonyum (I30E, Nanomer, Nanocor, USA) ile modifiye edilmiş organo-montmorillonit nanokilin Cr(VI) adsorpsiyonunda kullanımı ve kesikli sistemde incelenen prosese temas süresi, çözelti pH'sı, başlangıç metal konsantrasyonu ve adsorban miktarı gibi parametrelerin etkisi incelenmiştir. Cr(VI) iyon miktarının sulu çözeltilerdeki tayini UV-visible spektrofotometre ile gerçekleştirilmiştir. Cr(VI) iyonunun organokile adsorpsiyonunda pH 2'de maksimum kapasite gözlenirken, pHʼnın 2ʼden 6ʼya arttırılmasıyla kapasite azalmıştır. Adsorpsiyon izotermlerinden Langmuir ve Freundlich izotermleri deneysel verilerin uygunluğunu test etmek için kullanılmış olup Cr(VI) iyonlarının organokil kullanılarak giderilmesinde gerçekleşen adsorpsiyon reaksiyonlarının Langmuir izoterm modeline uygun olduğunu göstermiştir.

Anahtar Kelimeler

• Organokil
• Adsorpsiyon
• Cr(VI)

Kaynakça

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