Adsorption of 2,4-dichlorophenoxyacetic acid over Fe–Zr-based metal-organic frameworks: Synthesis, characterization, kinetics, and mechanism studies

Adsorption property and mechanism of glutaraldehyde-crosslinked chitosan for removal of 2,4-dichlorophenoxyacetic acid from water

“…It was reported that the affinity of 2,4-D for alcohols was stronger than the electrostatic interactions with GCC surface functional groups. 6 Therefore, ethanol was selected as the regeneration solvent. The 2,4-D adsorption capacity decreased from 48.7 to 40.8 mg g −1 when the adsorbent was regenerated with ethanol and reused five times.…”

“…5 A certain concentration of 2,4-D (0.14-0.24 μg g −1 ) was detected in the urine of adults and children in southern China. 6,7 The World Health Organization (WHO) designated 2,4-D as moderately hazardous (class II), and the United States Environmental Protection Agency (USEPA) categorized it as slightly to moderately toxic (class II-III). 8 As an important aspect of contamination, water plays an important role in the transmission of 2,4-D.…”

Silica-Coated Magnesium Ferrite Nanoparticles/Glutaraldehyde-Cross-Linked Polyethylenimine Composite Adsorbent for Ultrahigh Remediation of 2,4-Dichlorophenoxyacetic Acid

“…As given in Figure , the adsorption capacity for the 2,4-D removal was significantly decreased in the following order: SO 4 2– > CO 3 2– > NO 3 – ≈ Cl – . This could be rationalized by the shielding effect. , The introduction of salts in the adsorption system (i.e., increasing salinity) could result in disturbing the electrical double layer covering the surface charge of the adsorbent, leading to the reduction of interfacial electrokinetic potential. Consequently, this phenomenon could weaken the electrostatic attraction between the positive charge of the adsorbent and negative charge of 2,4-D.…”

“…Consequently, this phenomenon could weaken the electrostatic attraction between the positive charge of the adsorbent and negative charge of 2,4-D. Compared to monovalent ions (i.e., NO 3 – and Cl – ), higher negative charges of bivalent ions (i.e., SO 4 2– and CO 3 2– ) exhibited lower 2,4-D adsorption due to stronger binding with the positive charge of the adsorbent surface . This result could indicate that the electrostatic interaction is a dominant interaction for 2,4-D removal since the adsorption system was significantly influenced by coexisting ions …”

“…This result indicated that the desorption of 2,4-D could occur when the initial solution pH was tailored appropriately. Basically, an initial solution pH influences the adsorption capability, especially when an electrostatic interaction is involved in the adsorption process. , Therefore, these results implied the occurrence of electrostatic interaction between the MgFe 2 O 4 @SiO 2 /GA-PEI composite and 2,4-D molecules.…”