Increase In Removal Rate Research Articles

The impact of hemoglobin concentration on farrowing duration in sows

Abstract Concerns have been raised about the prevalence of anemia in sows, yet our understanding of its consequences, particularly its impact on the farrowing process, remains limited. This study investigated the relationship between hemoglobin concentration (HbC) and farrowing duration in sows. A total of 101 sows (n = 16 parity 0, 15 parity 1, 24 parity 2, and 46 parity 3 sows) were monitored for blood HbC (Hemocue Hb 201 device) from the ear vein before farrowing (d112 of gestation) and between 40 to 48h after farrowing (d2). Sows were categorized as anemic (HbC < 10 g/dL), or non-anemic (HbC ≥ 10 g/dL) based on their d112 HbC (i.e., pre-farrowing status). Surveillance cameras recorded the farrowing process for each sow, complemented by human observation. Farrowing duration was defined as the time elapsed between the first piglet born and the last piglet born. All piglets were individually weighed within 18h of birth, and stillborn piglets were identified using a lung flotation test conducted within 1h of birth. The correlation between sow HbC, farrowing duration, and stillborn piglets was assessed using the PROC CORR procedure in SAS. Additionally, the effect of HbC category on labor duration was tested using the PROC MIXED procedure, with total piglets born included as a covariate. Anemic sows had a prolonged farrowing (7.2 h ± 0.92 minutes, P < 0.001) compared to non-anemic sows (3.5 h ± 0.88 minutes) and negative correlation was observed between pre-farrow HbC and farrowing duration (r = -0.62, P < 0.001). There was a weak correlation between farrowing duration and stillborn piglets (r = 0.32, P = 0.01). No correlation was observed between farrowing duration and total born (r = 0.22, P = 0.11). There was no difference in total born (16.41 ± 0.7 vs 16.3 ± 0.7) between anemic (<10 g/dL) and non-anemic (≥ 10 g/dL) sows, respectively. Factors such as barn temperature on the day of parturition and feed intake the day prior did not influence the observed differences in labor duration between anemic and non-anemic sows. In conclusion, maintaining HbC above 10 g/dL appears beneficial for sows, as lower concentrations of HbC are associated with prolonged labor and increased removal rates. Blood HbC could serve as a valuable biomarker for identifying at-risk sows, thereby aiding in improving herd management and productivity.

Study on the Effect of Lignin Removal Rate on the Dielectric Properties of Delignified Materials

To investigate the relationship between the lignin removal rate change of wood and its dielectric properties, this study employed Mongolian Scotch Pine and Paulownia as the test materials. The acidic sodium chlorite method was used to delignify the treated material, and the lignin removal rate was determined at a specified reaction time interval to ascertain the dielectric constant and the tangent of the dielectric loss angle. The findings revealed that: As the delignification process progresses, the lignin content declines, accompanied by a reduction in the dielectric constant at elevated frequencies. This decline reaches a plateau near 10 MHz. The results demonstrated that the dielectric constant of the samples decreased with an increase in frequency and exhibited a stabilizing effect near 10 MHz. However, the dielectric constant of delignified wood was significantly higher than that of untreated wood. Additionally, the dielectric constant exhibited a linear relationship with the increase in lignin removal rate, while the tangent of the dielectric loss angle demonstrated a tendency to increase and then decrease. An investigation into the dielectric properties of delignified wood can yield valuable data and a theoretical foundation for the development of wood-based dielectric materials.

Efficient treatment of coking wastewater by coal-based activated carbon prepared through coal blending method

In this study, the adsorption performance of coal-based activated carbon produced from Shandong gas-fertilized coal, Taixi anthracite coal, and Datong weakly viscous coal, was investigated for coking wastewater treatment. All prepared activated carbons demonstrated excellent adsorption performance, boasting an iodine number surpassing 1000 mg/g and achieving a chemical oxygen demand determined by the dichromate method (CODcr) removal rate of over 85 % under static coking wastewater adsorption. A positive correlation exists between the total pore volume of activated carbon and its iodine number, methylene blue value, and caramel decolorization rate. Furthermore, dynamic adsorption experiments were conducted and there was an evident increase in the CODcr removal rate as the flow rate decreased. However, increasing the bed height beyond 400 mm only marginally enhanced the CODcr removal rate. The burn-off rate of activated carbon and the ratio of raw materials significantly influenced the pore structure. Notably, with a high anthracite ratio (40 %), elevating the burn-off rate (up to 70 %) did not enhance the effective porosity of activated carbon. The mesopore volume, particularly within 1.2–2.8 nm range, exerted a substantial influence on the coking wastewater adsorption efficiency. Overall, coal-based activated carbon demonstrated significant promise as a cost-effective adsorbent for coking wastewater treatment.

Advanced nanobubble flotation for enhanced removal of sub-10 µm microplastics from wastewater.

Sub-10 µm microplastics (MPs) in aquatic environments pose significant ecological and health risks due to their mobility and potential to carry harmful microcontaminants. Our effluent analysis from a Hong Kong Sewage Treatment Works shows that traditional treatment often fails to effectively remove these MPs. These small-sized MPs are commonly neglected due to challenges in accurate quantification, analysis, and removal. This study introduces a nanobubble-assisted flotation process that enhances the removal efficiency of both regular and irregular small-sized MPs from wastewater. The proposed process outperforms the traditional flotation process by fostering a more effective interaction between bubbles and MPs, increasing removal rates of MPs from 1 µm to 10 µm by up to 12% and providing a total efficiency boost of up to 17% for various particle sizes. Improvements are attributed to enhanced collision and adhesion probabilities, hydrophobic interactions, as well as better floc flotation. Supported by empirical evidence, mathematical models, and Molecular Dynamics simulations, this research elucidates the nanoscale mechanisms at play. The findings confirm the nanobubble-assisted flotation technique as an innovative and practical approach to removing sub-10 µm MPs in water treatment processes.

Complexity of influences on atrazine phytoremediation of coexisting graphene oxide in water: Mitigating its phytotoxicity while decreasing plant removal contribution

Phytoremediation is an efficient technology for the removal of herbicide atrazine (ATZ) contamination in water bodies, but its ability to reduce ATZ under combined pollution remains unclear, especially ATZ co-existing with the emerging pollutant graphene oxide (GO) that may have potential effects on ATZ fate, plants and microbes. Herein, we investigated the phytoremediation potential of an emergent plant (Iris pseudacorus) for ATZ and the response of bacteria in a hydroponic system with and without GO. The results showed that plants enhanced ATZ dissipation in water with the increased removal rate by a factor of 1.7–4.0. GO restricted ATZ uptake by plants, but favored ATZ bioconcentration in cell walls. The plant contributed most to changes in the bacterial communities, decreasing the alpha diversity, while enriching the functional categories involving in amino acid and carbohydrate metabolisms. These findings indicated that I. pseudacorus can be employed as an effective candidate of phytoremediation for ATZ co-existing with GO at environmentally relevant concentrations, tending to recruit bacteria with plant stress tolerance and growth-promotion activities more than with ATZ degradation activities; GO exerted a mitigating effect on ATZ stress improving the barrier function of cell walls, but decreased the contribution of plants to ATZ removal.

Removal of Moxifloxacin from Aqueous Solutions Using GO/Cr-MOFs.

The composite material, consisting of graphene oxide (GO) and chromium metal-organic frameworks (Cr-MOFs), was successfully synthesized by using a solvothermal method. The organic ligand employed was 2,5-dihydroxyterephthalic acid, while chromium acetate served as the source of the metal. The resulting material underwent characterization through Fourier transform infrared, scanning electron microscopy, and X-ray diffraction techniques. Subsequently, the adsorption capacity of the composite material toward moxifloxacin was evaluated. The results indicated a gradual increase in the moxifloxacin removal rate from GO/Cr-MOFs over time until reaching an equilibrium with a maximum removal rate of 90.4%. Additionally, it was observed that higher temperatures led to a decrease in the adsorption capacity. By incorporating 30 mg of GO/Cr-MOFs into a solution containing 40 ppm of moxifloxacin, the adsorption capacity could be maximized at 222.25 mg/g. Experimental data on MOF adsorption of moxifloxacin were analyzed using pseudo-first-order kinetics (PFO), pseudo-second-order kinetics (PSO), and Langmuir, Freundlich, and Temkin isotherm models for theoretical research purposes. Results showed that the PSO model exhibited a better correlation than the PFO model did. Furthermore, experimental data demonstrated good agreement with the Freundlich isothermal model, suggesting its effectiveness in accurately describing the adsorption process. Henceforth, it can be concluded that chemisorption plays a significant role in removing moxifloxacin by GO/Cr-MOFs. The van't Hoff equation analysis revealed an exothermic and spontaneous nature of moxifloxacin adsorption onto GO/Cr-MOFs. Compared to other materials, the GO/Cr-MOF composite exhibited high potential for applications such as drug removal or related fields.

Investigating micro-EDM machinability of Ti-35Nb-7Zr-5Ta (TNZT) alloy

ABSTRACT Titanium and its new-generation alloys are widely employed in high-end applications due to their special properties. Modern industries frequently use micro – Electro Discharge Machining (μ-EDM), a non-conventional machining technique that is especially useful for processing hard to machine materials like titanium alloys. μ-EDM can produce intricate shapes with excellent dimensional precision. The main emphasis of this work is an experimental analysis of the μ-EDM of TNZT alloy (Ti-35Nb-7Zr-5Ta) employing a tungsten carbide (WC) electrode. The results showed that with the increase in capacitance (C) 10nF to 100nF at Voltage (V) 80 V, the machining performance parameters such as material removal rate (MRR), overcut (OC), crater area, surface microhardness, and surface roughness increase by 6.38, 1.52, 4.66, 1.07, and 3.29 times, respectively. However, the circularity error of the µ-hole increases by 1.81 times. This study intends to show how the two key machining factors (C & V) influence significant machining performance parameters.

Experimental study of ECDM using a porous electrode containing internal micropores

ABSTRACT In electrochemical discharge machining (ECDM), continuous renewal of electrolyte between the tool electrode and the workpiece guarantees stable discharge machining. Proposed in this paper is Porous-electrode ECDM (p-ECDM) using a tool electrode made of porous material containing micrometer pores. The rough surface of the porous electrode promotes electrolyte regeneration between the electrodes to produce a stable and relatively thin gas film. At the same time, the internal connected micropores are used to provide controlled gas flow to the processing area, reduce the energy consumption of electrolytic bubbles, and improve the discharge energy to achieve efficient ECDM processing. Experimental results indicate that compared with a solid electrode, the porous electrode has faster electrolyte renewal, smaller bubble volume, more-stable voltage characteristics, 22.55% less overcut, a 4.7% smaller heat-affected zone, and better deep hole processing ability. Experimental results for p-ECDM assisted by controlled airflow demonstrate a 54.23% increase in the material removal rate.

A novel piezoelectric fenton-like process mediated by FeOCl for efficient contaminant removal

Ferric oxychloride (FeOCl), an iron-based catalyst with a unique coordination structure, has demonstrated effective pollutant removal capabilities in various reaction systems such as photo-Fenton, Fenton-like, and electro-Fenton processes. However, in previous studies, little or no attention has been paid by researchers to the piezoelectric properties of FeOCl and the pollutant removal performance exhibited in the presence of piezoelectric fields. In this study, we observed that the piezoelectric effect significantly enhanced the Fenton-like reaction process of FeOCl. Whereas the piezoelectric properties of FeOCl have not been reported in the previous research. The process significantly enhances the kinetic removal rate of pollutant, which is 3.12 times higher than the Fenton process and 18 times higher than the Fenton-like process for FeOCl. Furthermore, we observed a significant increase in the kinetic removal rate of pollutant after lattice distortion of FeOCl under the piezoelectric field and revealed how this process mediates the ultrafast oxidative removal process. Notably, we also detect the formation of pollutant polymeric products during the piezoelectric enhancement process, confirming the existence of a pollutant polymerization pathway during piezoelectric catalysis. The piezoelectric-enhanced FeOCl Fenton-like process constructed in this study not only provides important theoretical support for the practical application of FeOCl but also opens new research perspectives for the application of FeOCl in the field of piezoelectric catalysis.

Study on the polishing performance and mechanism of sapphire wafers by different types of degradable surfactants

Traditional chemical-mechanical polishing (CMP) slurry suffers from significant environmental pollution, and easy reaggregation of ultra-fine abrasives, all of which hinder its further application. In this study, the processing performance and mechanism of three different degradable surfactants to sapphire wafers were investigated, utilizing degradable aminomethylpropanol and xylitol as pH regulator and complexing agent of polishing slurry, respectively, which is aimed at solving the problem of the easy agglomeration of ultra-fine abrasives while achieving the super-precision and pollution-free process of sapphire wafers. After polishing, the surface roughness (Sa) of sapphire wafers decreases from 7.240 nm to 0.396 nm, which is 44.8 % lower than that without surfactant. Only <1 nm is the PV value, and there is a 12.9 % increase in the material removal rate. The action mechanism of biodegradable surfactants during CMP was revealed through TEM, XPS, electrochemical testing, contact angle measurement, and particle size analysis. The results showed that surfactants can effectively improve the wettability of the polishing slurry on the wafer and the dispersity of the ultra-fine abrasives in the slurry, thus facilitating the interfacial reaction between the sapphire surface and polishing slurry and the homogeneity of the material removal. This work truly realizes a green and pollution-free process that meets the requirements of ultra-smooth and efficient polishing of sapphire wafers.

Study on inclusion removal in two-strand tundish with gas curtain considering bubble-inclusion attachment

ABSTRACT Application of a gas curtain is one of the main means to improve the cleanliness of liquid steel in tundish. In particular, the bubble-inclusion attachment is one of the important ways to remove inclusions, which cannot be ignored. The bubble size and gas flow are the main parameters of the gas curtain. In this paper, the Euler–Lagrange–Lagrange approach is used to study the three-phase interaction behaviour of liquid steel, bubble, and inclusion. The effects of inclusion size, bubble diameter, and gas flow on inclusion removal rate were studied with normal continuous casting conditions. The calculation results show that the cleanliness of molten steel can be improved by replacing the dam with a gas curtain. In the range of gas flow rate from 1.35 to 2.15 Nm3 h−1, the removal rate of bubble-inclusion attachment and total inclusion removal rate increase with the increase of gas flow. In the range of diameter from 4.5 mm to 6.0 mm with the same gas flow, the total removal rate and bubble-inclusion attachment removal rate increase with the bubble size decrease. The results provide a reference for improving the cleanliness of molten steel by properly increasing the gas flow and reducing the bubble size in industrial operations.

Characteristics of Novel Heterotrophic Nitrification–Aerobic Denitrification Bacteria Bacillus subtilis F4 and Alcaligenes faecalis P4 Isolated from Landfill Leachate Biochemical Treatment System

Heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria are the key functional microorganisms needed to achieve simultaneous nitrification and denitrification (SND). In this study, 25 strains of HN-AD bacteria were successfully isolated from a stable landfill leachate biochemical treatment system, of which 10 strains belonged to Firmicutes and 15 strains belonged to Proteobacteria. Bacillus subtilis F4 and Alcaligenes faecalis P4 displayed good tolerance at a wide range of ammonia nitrogen (NH4+-N) concentrations. When the C/N ratio was 20, the removal rates of ammonia nitrogen were 90.1% and 89.5%, and the chemical oxygen demand (COD) removal rates were 92.4% and 93.9%, respectively. The napA gene encoding periplasmic nitrate reductase (Nap) and the nirS gene encoding nitrite reductase (Nir) were detected, and nitrogen balance showed assimilation and HN-AD was the main nitrogen metabolism mode in both strains. The use of immobilization materials could increase removal rate of ammonia nitrogen by 21.1% and 29.6%, respectively. The research results of this work can provide theoretical basis and technical support for the practical application of HN-AD bacteria to enhance the treatment of high ammonia nitrogen wastewater with high efficiency and low consumption.

Biochar enhanced anaerobic co-digestion of poultry litter and wheat straw: Performance, microbial analysis, and multiple factors’ interaction

Amendment of anaerobic co-digestion (Co-AD) of poultry litter (PL) and agricultural straw using biochar has rarely been practiced. This study conducted two sequential experiments to evaluate the effect of adding alkaline biochar on improving the batch Co-AD of PL and wheat straw. The feasibility experiment identified the advantages of adding biochar by the improved observed cumulative methane yield (CMYo, mL CH4/g VSsubstrate) of 9.7%; the increased removal rates of the substrate total solids (TSsubstrate) and volatile solids (VSsubstrate) of 15.2% and 14.2%, respectively; the enhanced abundance of both hydrolytic bacteria and methanogens, including hydrogegenotrophic Methanobacterium and, especially, the acetolactic Methanosaeta; and the 37.3% higher abundance of the methanogenic pathways, compared to the control. The interaction experiment showed that biochar dosage (BD) interacted with the initial substrate carbon-to-nitrogen ratio (C/N) and total solids level (TS). The developed mathematical models for CMYo and VSsubstrate removal by response surface methodology were significant, which predicted the optimal conditions being initial substrate C/N ratio 29.93 and TS 6.98%, and BD 9.98% substrate. The optimized CMYo and VSsubstrate removal were 17.7% and 22.1% higher, respectively, than those of the Control. These results support the utilization of biochar in improving the Co-AD of agricultural wastes.

Response characteristics of plants and pollutant removal in subsurface flow constructed wetlands under resting operation

The stable operation of subsurface flow (SSF) constructed wetlands (CWs) depends on the adopted maintenance and management strategies. To determine a suitable resting period for SSF CWs, this study investigated and compared the impacts of three resting periods on plant physiological metabolism, wetland purification effectiveness, and microbial responses. The results revealed that resting operations induced morphological adaptations in wetland plants, significantly enhanced the root-shoot ratio and specific root length. A 2-d resting period enhanced oxygen secretion from plant roots, which was beneficial for SSF CW reoxygenation, leading to significant increases in the average removal rates of chemical oxygen demand and total phosphorus. After the resting operation, the inorganic phosphorus solubilization and transporters function of rhizosphere microorganisms were enhanced, resulting in efficient phosphorus removal. The functional genes related to nitrification, nitrogen fixation, and assimilation were increased, and a 2–5 d resting period facilitated the aerobic nitrification in SSF CWs. Inversely, an excessively long resting (>5 d) significantly inhibits plant and microbial activity, resulting in a deteriorated pollutant removal performance. Plants regulate rhizosphere microorganisms by adjusting root traits, which are the key factors and important reference indicators guiding the formulation of the operation and maintenance strategies for SSF CWs during resting periods.

PERFORMANCE ENHANCEMENT OF BRASS EDM ELECTRODES WITH CRYOGENIC TREATMENT WHILE MACHINING THE COLD WORK STEEL AISI D2

This study investigates the performance of deep cryogenically treated brass (CuZn25Al5) electrodes in the die-sink EDM process. Two different cryogenic treatment durations, 6 h and 12 h, were applied to 8 mm diameter electrodes, and their effects were compared to untreated electrodes. The machining tests were conducted under moderate and aggressive conditions. In the machining tests, the 6-h cryo-treated electrode exhibited a 16.8% increase in material removal rate (MRR) under moderate conditions and a 19.7% increase under aggressive conditions compared to the reference electrode. The 12-h cryo-treated electrode showed similar MRR values to the reference electrode but improved tool wear resistance by 9.4% under moderate conditions. The kerf angle was minimized, indicating better hole verticality, in the 6-h cryo-treated electrode group. The improvement in machining performance was attributed to the enhancement in electrical conductivity of the electrodes, which increased by 28% for the 6-h cryo-treated electrode and 20% for the 12-h cryo-treated electrode. X-ray diffraction (XRD) analysis revealed shifts in peak positions and possible phase transformations due to cryogenic treatment. Surface roughness measurements showed improved surface conditions in the cryo-treated electrodes under aggressive conditions. The results indicate that cryogenic treatment enhances MRR, reduces tool wear, and improves surface quality in die-sink EDM. These improvements are attributed to increased electrical conductivity and changes in the internal structure of the brass electrode.

Laser surface structuring of titanium alloy (Ti-6Al-4V) for improved tribocorrosion resistance for bio-implant applications

In this study, laser surface structuring (LSS) of titanium alloy (Ti-6Al-4 V) using pulsed Nd: YLF laser with 100 ns pulse duration at various laser powers, scan speeds, and line-spacings has been undertaken for improving the tribocorrosion property. Due to LSS, there is an increment in nano hardness (4.9 GPa - 6.3 GPa) and Young's modulus (140 GPa − 153 GPa) when compared to untreated Ti-6Al-4 V (3.9 GPa, 123 GPa). The tribocorrosion behavior in simulated body fluid against the ZrO2 ball in fretting mode shows that due to LSS, the degradation rate was significantly reduced (5.3–67.2%) when compared to the untreated one. With an increase in load, the coefficient of friction and material removal rate increases. The mechanism of tribocorrosion is established.

Process Damping Identification Using Bayesian Learning and Time Domain Simulation

Abstract Process damping can provide improved machining productivity by increasing the stability limit at low spindle speeds. While the phenomenon is well known, experimental identification of process damping model parameters can limit pre-process parameter selection that leverages the potential increases in material removal rates. This paper proposes a physics-informed Bayesian method that can identify the cutting force and process damping model coefficients from a limited set of test cuts without requiring direct measurements of cutting force or vibration. The method uses time-domain simulation to incorporate process damping and provide a basis for test selection. New strategies for efficient sampling and dimensionality reduction are applied to lower computation time and minimize the effect of model error. The proposed method is demonstrated, and the identified cutting and damping force coefficients are compared to values obtained using machining tests and least-squares fitting.

Experimental study on removal of hydrogen sulfide gas by spray and bubble blowing: A comparative study

H2S (hydrogen sulfide) is widely concerned because of its strong odor and toxicity, which seriously affects the physical and mental health of surrounding residents. In this paper, bubble blowing and spray deodorization experimental systems for H2S gas generation were constructed, with plant-derived deodorant were employed as a deodorizing liquid. The influence factors of spray and bubble blowing deodorization experimental system for deodorization performance were explored. And the effects of spray deodorization method and bubble blowing deodorization method on H2S removal rate were compared. The results show a positive correlation between the removal rate of H2S and the inlet pressure in the spray deodorization system. As the inlet pressure increases, the removal efficiency of H2S exhibits a gain ranging from 22.36% to 23.56%. Within the bubble blowing deodorization system, H2S concentration decreases as the deodorization solution dosage increases. As the deodorizing solution dosage increases from 920 mL to 1800 mL, H2S concentration decreases from 0.46 mg·m−3 to 0 mg·m−3. Furthermore, the bubble blowing deodorization method outperforms the spray, resulting in a 14.60–29.09% increase in H2S removal rate. The bubble blowing deodorization method proposed in this study exhibits promising potential for application in the field of malodorous gas treatment.

An overlooked effect of hydroxylamine on anammox granular sludge: Promoting granulation and boosting activity

The exogenous hydroxylamine dosing has been proven to enhance nitrite supply for anammox bacteria. In this study, exogenous hydroxylamine was fed into a sequencing batch reactor to investigate its long-term effect on anammox granular sludge. The results showed that hydroxylamine enhanced the reactor's performance with an increase in total nitrogen removal rate from 0.23 to 0.52 kg N/m3/d and an increase in bacterial activity from 11.65 to 78.24 mg N/g VSS/h. Meanwhile, hydroxylamine promoted granulation by eluting flocs. And higher anammox activity and granulation were supported by extracellular polymeric substances (EPS) characteristics. Moreover, Candidatus Brocadia's abundance increased from 1.10 % to 3.03 %, and its symbiosis with heterotrophic bacteria was intensified. Additionally, molecular docking detailed the mechanism of the hydroxylamine effect. Overall, this study would provide new insights into the hydroxylamine dosing strategy application.

Efficient adsorption removal of 2,4-dichlorophenoxyacetic acid using amine-functionalized metal–organic frameworks (MOFs): Performance and mechanisms

2,4-dichlorophenoxyacetic acid (2,4-D) is a widely used herbicide and plant growth regulator worldwide; however, its overdose and improper use would cause severe eco-toxicological effects on aquatic life, plants, and human life. This work synthesized high-quality MIL-101(Cr)-NH2 nanoparticles via a one-pot hydrothermal reaction and used it in pioneer as an amine-functionalized mesoporous metal–organic frameworks (MOFs) adsorbent for 2,4-D removal. The adsorption kinetics results confirmed that MIL-101(Cr)-NH2 obeys the pseud-second-order kinetic model, and the isotherm results imply that it shows multilayer adsorption following the Freundlich model. Compared to state-of-the-art benchmark MOF adsorbent UiO-66-NH2, MIL-101(Cr)-NH2 achieved a superior 2,4-D adsorption capacity of 348.5 mg/g at pH = 7 with a nearly 50 % increase in adsorption removal rate under ambient conditions. Spectroscopy analysis and density functional theory (DFT) calculations revealed that the distinct large pore size, high surface area and porosity of MIL-101(Cr)-NH2 are the essential physical factors for enhancing the diffusion ability of 2,4-D in the framework. Meanwhile, the electrostatic interactions of the metal clusters and aminated benzene ring with the dissociated 2,4-D anion are the dictated binding forces during adsorption. This mechanism was further validated by the adsorption behaviors of other contaminants over the two MOF adsorbents. Furthermore, the MIL-101(Cr)-NH2 nanoparticles can be chemically anchored onto chitosan to form MIL-101(Cr)-NH2/Chitosan foams with feasible recovery ability and it was found that the MIL-101(Cr)-NH2/Chitosan (1/3) foam showed a comparable 2,4-D removal rate to UiO-66-NH2 (52.2 % vs. 57.7 %). This study reported a high-performance aminated MOF adsorbent for 2,4-D removal and the revealed adsorption mechanisms offer an excellent platform for rational design of advanced adsorbents for acidic contaminants adsorption.