ADSORPTION OF DIAZO DYE DIRECT RED-28 AND TETRA-AZO DYE DIRECT BLACK-22 USING CALCINED KAOLIN IN AQUEOUS SOLUTIONS
Yükleniyor...
Dosyalar
Tarih
2023
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
CHEM SOC ETHIOPIA
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
ABSTRACT. In this study, the removal of diazo and tetra-azo dyes using calcined kaolin were compared. Direct red-28 (DR-28) and Direct black-22 (DB-22) was chosen as diazo and tetra-azo dyes, respectively. The kaolin obtained from Turkiye and calcined at 200 °C was found to be the most efficient adsorbent. Natural and calcined kaolins were characterized using SEM-EDS, FTIR, TGA, and XRD. The parameters such as, calcination temperature of the kaolin, adsorbent amount, temperature, initial pH, contact time, and initial concentration were studied. It was found that the removal rate of DR-28 was higher than that of DB-22 at the studied conditions. The removal of DR-28 and DB-22 were found to be 90.1% and 46.2% under the following conditions: adsorbent amount: 1.2 g/200 mL, initial concentration: 20 mg/L, original pH, temperature: 20 °C and contact time 120 min. The adsorption of the dyes was fitted to Langmuir isotherm model. The maximum adsorption capacity of calcined kaolin at 200 °C was determined as 5.39 and 3.5 mg/g for DR-28 and DB-22, respectively. The adsorption of DR-28 and DB-22 followed a pseudo-second order model. The thermodynamic study showed that the adsorption of DB-22 onto calcined kaolin was endothermic while that of DR-28 was exothermic.
Açıklama
Anahtar Kelimeler
Adsorption, Diazo dye, Tetra-azo dye, Kaolin
Kaynak
BULLETIN OF THE CHEMICAL SOCIETY OF ETHIOPIA
WoS Q Değeri
Q4
Scopus Q Değeri
Cilt
37
Sayı
3
Künye
Findik, S. (2023). Adsorption of diazo dye direct red-28 and tetra-azo dye direct black-22 using calcined kaolin in aqueous solutions. Bulletin of the Chemical Society of Ethiopia, 37(3), 593-610.
