İyon-Seçici Elektrotlar Kullanılarak Çevre Numunelerindeki Sularda Sertlik Tayini

Abstract

Bu çalışmada, suyun sertliğinin belirlenmesinde kullanılmak üzere ticari olarak satın alınan iyonofor maddeler ile Ca²⁺ ve Mg²⁺-seçici mikro boyutta potansiyometrik PVC-membran elektrotlar geliştirildi. Hazırlanan Ca²⁺ ve Mg²⁺-seçici elektrotların potansiyometrik performans karakteristikleri belirlendi ve ölçümlerde ana iyon çözeltisine karşı her 10 kat konsantrasyon değişimi için sırasıyla ortalama 23.5 ve 27.6 mV potansiyel farkı gözlendi. Elektrotların, 1x10^-1-1x10^-5 mol L^-1 derişim aralığında ana iyon çözeltisine karşı doğrusal davranış sergilediği, alkali ve toprak alkali metal iyonlarının yanında ana iyona karşı oldukça seçici olduğu belirlendi. Laboratuvarda hazırlanan potansiyometrik PVC-membran iyon-seçici elektrotlar kullanılarak çevre numunelerdeki suların sertlik tayini durgun ortamda gerçekleştirildi. Ayrıca, su numunelerinin sertliği standart sertlik tayin yöntemi olan kompleksometrik EDTA titrasyonu ile de yapıldı. Daha sonra numunelerin sertlikleri AAS tekniği kullanılarak analiz edildi ve tüm ölçümler potansiyometrik sonuçlarla karşılaştırmalı olarak verildi. Elde edilen sonuçlar, geliştirilen Ca²⁺ ve Mg²⁺-seçici mikro boyutta potansiyometrik PVC-membran elektrotların sulardaki sertlik tayininde rutin olarak kullanılabileceğini göstermektedir.

Keywords

• İyon-seçici PVC-membran elektrot,Potansiyometri,, Suda sertlik tayini

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