Removal of Rhodamine B (A Basic Dye) and Acid Yellow 17 (An Acidic Dye) from Aqueous Solutions by Ordered Mesoporous Carbon and Commercial Activated Carbon

Katarzyna Jedynak,Dariusz Wideł,Nina Rędzia

doi:10.3390/colloids3010030

Abstract

In this work, adsorption of rhodamine B (RB) and acid yellow 17 (AY17) was investigated on ordered mesoporous carbon material obtained by soft-templating method with hydrochloric acid (ST-A). For comparison, the adsorption process on commercial activated carbon CWZ-22 was also carried out. The sorbents were characterized by nitrogen adsorption/desorption isotherms and scanning electron microscopy. Langmuir and Freundlich adsorption isotherm models were applied to simulate the equilibrium data of RB and AY17. Adsorption isotherm data could be better described by the Langmuir model than the Freundlich model. The adsorption kinetics of RB and AY17 on studied carbons could be well depicted by using pseudo-second-order kinetic modeling. The adsorption capacity increased with temperature increase in the range of 298–315 K. In the whole diffusion process, the intraparticle diffusion was involved, but not the whole rate-controlling step. The calculated thermodynamic parameters, including Gibbs free energy (∆G), enthalpy (∆H), and entropy (ΔS) suggested that adsorption processes of RB and AY17 on ST-A and CWZ-22 were endothermic and spontaneous.

Highlights

IntroductionIn the textile and dye industry, synthetic dyes are very often used and, have a harmful effect on human and animal health [2]
The adsorption results (Table 6) confirmed that the adsorption kinetics for rhodamine B (RB) and acid yellow 17 (AY17) on studied carbon materials can be described by pseudo-second-order kinetic equation
Ordered mesoporous carbon and commercial activated carbon were applied in adsorption studies of rhodamine B and acid yellow 17

Summary

Introduction

In the textile and dye industry, synthetic dyes are very often used and, have a harmful effect on human and animal health [2] These colorful compounds affect the change in the color of water and, have a detrimental effect on fauna and flora [3]. Even at low concentrations, have toxic and carcinogenic effects and can affect water organisms and the digestive system of humans [4]. They are extremely resistant to the effects of temperature, light, and other factors, such as chemicals, and are extremely difficult to remove [5]. The adsorption process is primarily simple and has many economic advantages, but it is worth considering that it catches toxic substances at very low concentrations [1,10]

Methods

Results

Conclusion