Enhanced Removal of Bordeaux B and Red G Dyes Used in Alpaca Wool Dying from Water Using Iron-Modified Activated Carbon

Abstract

The aim of this research was to explore the removal of Red G and Bordeaux B dyes from water using a packed bed column with conventional carbon (C-conv) and iron-modified activated carbon (C-FeCl3). The bands increased in C-FeCl3, corresponding to groups already existing in C-conv, such as C = C and C-C, and the appearance of new groups, such as C-O, C-Cl, Fe-Cl and Fe-O. The total ash content (CT) was CT = (10.53 ± 0.12 and 8.98 ± 0.21)% for C-conv and C-FeCl3, respectively. A molecular structure in the shape of a cross was noticed in Bordeaux B, which was less complex and smaller than the one in Red G. For fixed-bed columns, the carbon fraction was (0.43 and 0.85) mm. The pH of the adsorbents was 8.55 for C-conv and 4.14 for C-FeCl3. Breakthrough curves were obtained and the Thomas model (TM) and Yoon–Nelson model (YNM) were applied. The sorption capacity of Bordeaux B on C-conv and C-FeCl3 was qTH: (237.88 and 216.21) mg/g, respectively, but the one of Red G was qTH: (338.46 and 329.42) mg/g. The dye removal (RT) was over 55%.

Keywords

• iron-modified activated carbon
• azo dyes
• fixed-bed columns
• adsorption