Öz

Çeşitli antropojenik faaliyetler sonucu ağır metallerin neden olduğu su kirliliği, temiz su kaynaklarını tehdit eden önemli bir küresel sorun olmaya devam etmektedir. Geleneksel su arıtma yöntemleri maliyetli olup, potansiyel çevresel dezavantajları da bulunmaktadır. Bu nedenle, uygun maliyetli ve biyolojik olarak parçalanabilir arıtma tekniklerinin geliştirilmesi zorunludur. Bu çalışmada, sudan ağır metallerin uzaklaştırılması için fil otundan (Pennisetum purpureum) elde edilen modifiye edilmemiş ve EDTA ile modifiye edilmiş selülozun adsorpsiyon kapasiteleri değerlendirilmiştir. Fil otu Enugu, Nijerya’dan toplanmıştır. Örnekler yıkanmış ve gölgede kurutulmuştur. Alkali işlem ve ağartma yoluyla selüloz ekstraksiyonu yapılan selüloz, adsorpsiyon özelliklerini geliştirmek için EDTA ile modifiye edilmiştir. Modifiye edilmemiş ve EDTA ile modifiye edilmiş selüloz liflerinin sulu çözeltilerden ağır metalleri adsorbe etme kapasitelerini değerlendirmek için kontrollü koşullar altında toplu adsorpsiyon deneyleri gerçekleştirilmiştir. Adsorpsiyon öncesi ve sonrası metal iyon konsantrasyonları alev atom absorpsiyon spektrofotometresi kullanılarak ölçülmüş ve adsorpsiyon kapasiteleri buna göre hesaplanmıştır. Modifiye edilmemiş ve edilmiş selüloz en yüksek afiniteyi sırasıyla Hg(II) ve Cd(II) için göstermiştir. Her iki selüloz tipi çözeltilerden yaklaşık %70 oranında Hg ve Cd iyonlarını etkili bir şekilde uzaklaştırmıştır. Bulgular, modifiye edilmemiş selülozun Hg gideriminde özellikle etkili olduğunu, modifiye selülozun ise Cd adsorpsiyonunda üstün olduğunu göstermiştir. Bu sonuçlar, her iki tip selülozun belirli kirleticilere karşı hedefli arıtma potansiyeline sahip olduğunu düşündürmektedir. Sonuçlar bu maddelerin ağır metal arıtımı için uygun maliyetli ve biyolojik olarak parçalanabilir çözümler olarak ele alınabileceklerine işaret etmektedir.

Assessment of the lead, cadmium, mercury, and arsenic adsorption capacities of edta-modified and umodified cellulose fibres from elephant grass (Pennisetum purpureum)

Abstract

Heavy metal pollution of water caused by various anthropogenic activities remains a significant global challenge, threatening the supply of clean water. Conventional water remediation approaches are costly with potential environmental risks. Thus, the development of cost-effective and biodegradable remediation methods is imperative. This study assessed the heavy metal adsorption capacities of native and EDTA-modified elephant grass (Pennisetum purpureum) cellulose. Elephant grass was collected from Enugu, Nigeria. The samples were washed and shade-dried. Cellulose was extracted via alkali treatment and bleaching, and then modified with EDTA to enhance its adsorptive properties. Batch adsorption experiments were designed to evaluate the capacities of unmodified and modified cellulose fibers to adsorb heavy metals from aqueous solutions under controlled conditions. The metal ion concentrations before and after adsorption were measured using flame atomic absorption spectrophotometry, and the adsorption capacities were calculated. The unmodified and modified cellulose exhibited the highest affinity for Hg(II) and Cd(II), respectively. Both types effectively removed ~70% of the Hg and Cd ions from solution. These results indicated that the unmodified cellulose was particularly effective for Hg removal, while the modified cellulose excelled in adsorbing Cd. They suggest the potential of these materials for the targeted remediation of specific contaminants and also identify them as cost-effective and biodegradable solutions for remediating heavy metal pollution.

Keywords

• Cellulose
• heavy metals
• biodegradable
• remediation
• adsorption

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