Adsorption of 2,4-dichlorophenoxyacetic acid on activated carbon

Preparation of 2,4‐dichlorophenoxyacetic acid loaded on cysteamine‐modified polydopamine and its release behaviors

“…2,4‐Dichlorophenoxyacetic acid (2,4D) is the third most widely used herbicide worldwide . Considering the fact that 2,4D has a carboxyl structure and the amino group of NHSH grafted onto the PDA nanosphere retains its reactivity, they can form an amide bond via a condensation reaction between the carboxyl and amino groups.…”

“…2,4-Dichlorophenoxyacetic acid (2,4D) is the third most widely used herbicide worldwide. [22][23][24] Considering the fact that 2,4D has a carboxyl structure and the amino group of NHSH grafted onto the PDA nanosphere retains its reactivity, they can form an amide bond via a condensation reaction between the carboxyl and amino groups. The amide bond makes the connection between the vehicle and cargo behave much more stably and makes it less susceptible to chemical hydrolysis.…”

Study of the adsorption of 2,4‐dichlorophenoxyacetic acid from the aqueous solution onto activated carbon

“…Among of them carbon nanotubes (CNTs) has known as potential material and there have been much effort on the purification of CNTs to improve their adsorption capability [1] and the nature of thermodynamics and kinetics of the adsorption of 2,4-D as well. In our previous paper, [2] we reported that the CNTs with the surface area of 267 m 2 g -1 exhibited a maximum adsorption capacity of 84.034 mg g -1 or 314 µg m -2 at 283 K. [2] Nevertheless, it was mentioned in some international papers [3,4] that activated carbon (AC) possessed good adsorption capability to 2,4-D in the aqueous solution. Therefore, AC is a promising adsorbent for the removal of above herbicides from the contaminated solution.…”

“…al. [3] indicated that the adsorption of 2,4-D on AC followed three models: Langmuir, Freundlich and Temkin, however, there was no mention about the best fitting model for describing the adsorption. In another paper, [4] it was indicated that Langmuir was the more fitting model for the adsorption of 2,4-D on AC than Freundlich based on the correlation coefficient R 2 , while Langmuir model is only suitable for the uniform adsorption surface.…”

“…In another paper, [4] it was indicated that Langmuir was the more fitting model for the adsorption of 2,4-D on AC than Freundlich based on the correlation coefficient R 2 , while Langmuir model is only suitable for the uniform adsorption surface. Both papers [3,4] indicated that the pseudo-second-order kinetic model was fit with the adsorption, however, there was no mention on the diffusion kinetic model. Besides, investigations of the temperature effect and thermodynamic parameters on the adsorption were also not mentioned to indicate the nature and the trend of the adsorption on AC.…”