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[Display omitted] The tunable porous structure of metal organic frameworks (MOFs) plays a crucial role in determining their adsorption performance. In this study, we developed and employed a strategy involving monocarboxylic acid assistance to synthesize a series of zirconium-based MOFs (UiO-66-F 4) for the removal of aqueous phthalic acid esters (PAEs). The adsorption mechanisms were investigated by combining batch experiments, characterization and theoretical simulation. By adjusting the affecting factors (i.e., initial concentration, pH values, temperature, contact time and interfering substance), the adsorption behavior was confirmed as a spontaneous and exothermic chemisorption process. The Langmuir model provided a good fit, and the maximum expected adsorption capacity of di- n -butyl phthalate (DnBP) on UiO-66-F 4 (PA) was calculated to be 530.42 mg·g−1. Besides, through carrying out the molecular dynamics (MD) simulation, the multistage adsorption process in the form of DnBP clusters was revealed on a microcosmic scale. The independent gradient model (IGM) method showed the types of weak interactions of inter-fragments or between DnBP and UiO-66-F 4. Furthermore, the synthesized UiO-66-F 4 displayed excellent removal efficiency (>96 % after 5 cycles), satisfactory chemical stability and reusability in the regeneration process. Hence, the modulated UiO-66-F 4 will be regarded as a promising adsorbent for PAEs separation. This work will provide referential significance in tunable MOFs development and actual applications of PAEs removal. [ABSTRACT FROM AUTHOR]

[Display omitted] • Defect content and particle size of MOF-808 can be tuned using iron nitrate. • The modulating MOF-808 can achieve effective removal and recovery of phosphate. • Adsorption mechanisms involve electrostatic attractions and ligand exchange. In this work, a facile and green method is applied to synthesize hydrophilic MOF-808(Zr) and modulate its defect content and particle size using different amounts of iron nitrate (denoted as F) to obtain serial XF-MOF-808 ("X" implied the dosage of used F). The development of additional adsorption sites and the fine-tune of pore and particle size based on MOF-808 significantly improved phosphate adsorption performance. In particular, the 0.5F-MOF-808 shows excellent adsorption capacity (305.5 mg/g) and rapid diffusion rate (37.51 mg/g·min0.5) for phosphate at 298 K and initial pH = 6.5, outperforming pristine MOF-808 and most previously reported adsorbents. 0.5F-MOF-808 possesses a wide pH tolerance, outstanding reusability and excellent selectivity for phosphate adsorption from simulated wastewater, verified in environmental implication and regeneration experiments. Phosphate loaded on the adsorbent can be converted to struvite for agricultural fertilizer via a simple crystallization process. Compared to MOF-808, the exceptional sorption performance of 0.5F-MOF-808 is supported by decreased internal diffusion limitation, enlarged pore size and the development of new adsorption sites, which can be proved by advanced characterizations and batch adsorption experiments. This work presents a promising modification strategy of MOF materials for phosphate adsorption and recovery. [ABSTRACT FROM AUTHOR]