Iron Acetylacetonate Research Articles

Correction: Mu et al. Preparation and Characterization of Corn Straw-Based Graphitized Carbon with Ferric Acetylacetonate as Catalyst. Processes 2023, 11, 2884

In the original publication [...]

N-coordinated iron sites dispersed in porous carbon frameworks to activate peroxymonosulfate for efficient sulfisoxazole degradation and real hospital wastewater decontamination

Herein, an N-coordinated Fe site dispersed in porous carbon frameworks (Fe-NC) fabricated from zeolitic imidazolate frameworks encapsulated with iron acetylacetonate (Fe(acac)3 @ZIFs) was employed to activate peroxymonosulfate (PMS) for the attenuation of sulfisoxazole (SIZ) and treating real hospital wastewater. The constructed Fe-NC/PMS system exhibited good catalytic stability for SIZ degradation, maintaining excellent degradation performance over multiple cycles with virtually no leaching. The quenching experiments, electron paramagnetic resonance (EPR) capture analyses, and semi-quantitative measurements showed that singlet oxygen (1O2) and high-valent metal-oxo species were mainly responsible for SIZ degradation by Fe-NC/PMS. Significantly, ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) was used to trace 134 pharmaceutical contaminants in real hospital wastewater. Effective degradation was achieved for 87 % of the pharmaceutical contaminants by the Fe-NC/PMS process. Seventy-four pharmaceutical contaminants were eliminated. Taken together, this work successfully established the Fe-NC/PMS technology using the developed iron-based materials and explored its application to real hospital wastewater treatment, providing an eco-friendly and effective strategy for treating wastewater.

High-concentrated synthesis of surface modified iron oxide nanoparticles using ethanol-enhanced supercritical CO2 media

In the synthesis of surface modified metal oxide nanoparticles (NPs), supercritical CO2 is an attractive medium to achieve a simple and green chemistry approach without waster liquor. However, the mass production of surface-modified NPs is still a serious challenge for their industrial utilization. In this work, we aimed to demonstrate the high-concentrated synthesis of surface-modified iron oxide NPs in ethanol-enhanced supercritical CO2. The synthesis and phase observation were performed at 30.0 ± 0.8 MPa of CO2, 100 °C and 18 h, while changing the total concentration of iron(Ⅲ) acetylacetonate, water and oleic acid and ethanol ratio. As a result, lower total concentration gave single nano-sized α-Fe2O3 nanocrystal under uniform phase while higher one gave aggregated α-FeOOH under ununiform phase. However, ethanol entrainer successfully homogenized the reaction field by drastically raising the solubilities of components, allowing the high-concentrated synthesis of single nano-sized α-Fe2O3 nanocrystal. Furthermore, synthesized nanocrystal had chemically and densely modified surface, showing the unimodal size distribution in cyclohexane. These results conclusively show that supercritical CO2 with ethanol entrainer is a promising medium to allow the mass production of densely modified nanocrystal and subsequent their industrial utilization in thin film fabrication and drug delivery system.

Enhanced functionalization of superparamagnetic Fe3O4 nanoparticles for advanced drug enrichment and separation applications

Backgroundsuperparamagnetic ferroferric oxide (Fe3O4) nanoparticles can be extensively functionalized for applications in drug enrichment and separation. Their high magnetic responsiveness and controllable surface modification enable rapid drug enrichment and separation under external magnetic fields. This study aimed to enhance the application potential of superparamagnetic Fe3O4 nanoparticles in the field of drug enrichment and separation by functionalizing these nanoparticles to improve their biocompatibility and targeting capabilities.Methodssuperparamagnetic Fe3O4 nanoparticles functionalized with dopamine were synthesized using benzyl alcohol as the solvent and iron acetylacetonate as the precursor. The dopamine-functionalized superparamagnetic iron oxide nanoparticles were used to analyze protein enrichment and separation. Characterization of the nanoparticles was conducted, including analysis of particle size distribution, Zeta potential, and fluorescence spectra using a fluorescence spectrophotometer.Resultsthe Fe3O4 nanoparticles maintained high magnetism from the original material and exhibited uniform particle size distribution and stable Zeta potential. The saturation magnetization of dopamine-functionalized superparamagnetic Fe3O4 nanoparticles showed no significant difference compared to before coating, indicating minimal influence of dopamine on the internal magnetic core of the nanoparticles. The Fe3O4 nanoparticles demonstrated good biocompatibility and stability.Conclusionfunctionalization of superparamagnetic Fe3O4 nanoparticles significantly enhances their efficiency in drug enrichment and separation processes, suggesting broad applications in the pharmaceutical industry.

Study of curing kinetics of 4‐ (dimethylsilyl) butyl ferrocene grafted HTPB and effect of catalysts by differential scanning calorimetry

AbstractThe cure kinetics of 4‐ (dimethylsilyl) butyl ferrocene grafted hydroxyl terminated polybutadiene (HTPB) with Isophorone diisocyante (IPDI) was investigated using differential scanning calorimeter (DSC). Furthermore, the catalytic effect of Iron (III) acetylacetonate (Fe(AA)3) and Dibutyltin dilaurate (DBTDL) on the curing reaction was studied. The experimental data was fitted to Kissinger and Ozawa models, and the kinetic parameters were expressed as Arrhenius activation energy (E), pre‐exponential factor (A) and rate constants. The Crane model was explored to determine the reaction order of the curing reaction. The study categorically showed that the activation energy of the curing reaction with 4‐ (dimethylsilyl) butyl ferrocene grafted HTPB is higher as compared to the pure hydroxyl terminated polybutadiene (HTPB) based system. However, the rate of curing reaction is higher with 4‐ (dimethylsilyl) butyl ferrocene grafted HTPB as compared to HTPB, and the viscosity build‐up data is too aligned with the DSC kinetic study. In addition, both catalysts increased the rate of the curing reaction but Fe(AA)3 displayed a superior catalytic effect.

Advanced oxidation processes of persulfate coupled with sequencing batch reactor activated sludge process (AOPs-SBR): Biodegradability and toxicity analysis of degradation intermediates

Although carbon-based catalysts are of great significance for potential application in advanced oxidation processes of persulfate, the biotoxicity and biodegradability of degradation intermediates of organic pollutants have been rarely reported. Herein, carbon-based nanofiber materials are prepared by electrospinning energetic metal–organic framework (EMOF) and ferric acetylacetonate, where the puff up of the EMOF creates hierarchical porous structure during high-temperature pyrolysis and provides sufficient space to expose Fe/N active sites. When organic pollutant tetracycline (TTCH) as target contaminant, energetic MOF derived carbon/Fe nanofiber in 900C named ECFe-9, which exhibits larger specific surface area (546.8 m2/g) and higher reaction rate constant k value (0.186 min−1) than that of in 700, 800 and 1000 °C. The biotoxicity of degradation intermediates is investigated by toxicity simulation. The biodegradability is analyzed by using advanced oxidation coupled with sequencing batch reactor activated sludge process (AOPs-SBR). This study provides a new perspective for advanced oxidation processes of persulfate as pretreatment methods for aerobic biochemical degradation of persistent organic pollutants.

Increasing the Particle Size and Magnetic Property of Iron Oxide Nanoparticles through a Segregated Nucleation and Growth Process.

Iron oxide nanoparticles (IONs) with good water dispersibility were prepared by the thermal decomposition of iron acetylacetonate (Fe(acac)3) in the high-boiling organic solvent polyethylene glycol (PEG) using polyethyleneimine (PEI) as a modifier. The nucleation and growth processes of the crystals were separated during the reaction process by batch additions of the reaction material, which could inhibit the nucleation but maintain the crystal growth, and products with larger particle sizes and high saturation magnetization were obtained. The method of batch addition of the reactant prepared IONs with the largest particle size and the highest saturation magnetization compared with IONs reported using PEG as the reaction solvent. The IONs prepared by this method also retained good water dispersibility. Therefore, these IONs are potentially suitable for the magnetic separation of cells, proteins, or nucleic acids when large magnetic responses are needed.

Composite hydrogel derived iron/nitrogen co-doped carbon for bisphenol A removal

Conventional carbon-based adsorbents encounter insufficient active sites, low adsorption efficiency and poor anti-interference ability for bisphenol A (BPA) removal. Herein, we developed a cellulose nanocrystal/polyacrylic acid hydrogel derived strategy for the preparation of a novel iron/nitrogen co-doped carbon (FeN@CP800) via simple immersion of iron (III) acetylacetonate and melamine in hydrogel precursors and further carbonization at 800 °C. The precursor scaffold interacted with active species source by swelling behavior to form hydrogen bonds and Fe coordination, thereby facilitating subsequent growth of multiple active conformations without aggregation. The hierarchical porous surface morphology, abundant N doping, multi-active site structure and large specific surface area significantly improved the accessible BPA adsorption of FeN@CP800. The maximum adsorption capacity calculated by Langmuir model was 309.17 mg·g−1, 4.5 times higher than that of bare CP. Benefited from pore filling, hydrogen bonds, π-π stacking and hydrophobic interactions, the excellent adsorption performance of FeN@CP800 was retained under varied coexisting ions species, ionic strength and solution pH with 84 % capacity retention after 5 cycles. DFT calculations disclosed the Fe4N component was the predominant active sites to improve the adsorption and interfacial transfer process. Thus, these findings provide a new strategy to design high-performance adsorbent for phenolic pollutants removal in water.

Construction of iron oxide@C@Fe heterointerfaces by oxygen atmosphere heat treatment for enhanced microwave absorption performance

Carbon and iron-based materials are the two most extensively implemented microwave absorption materials. In this paper, carbon/iron-based wave absorption composite materials with tremendous dielectric and magnetic loss were successfully synthesized by carbonizing iron (Ⅲ) acetylacetonate (Fe(acc)3). The heterointerfaces were constructed by oxidation heat treatment to further regulate the dielectric loss and optimize the impedance matching of the composite, and improve the microwave absorption performance. Eventually, ultra-thin lightweight composite materials were prepared. When the thickness of the absorbing coating was only 1.01 mm, the minimum reflection loss (RLmin) value of the composite was −15.8 dB with 50 % filling. In addition, the effective absorption bandwidth (EAB) (RL ≤ -10 dB) was highly up to 8.8 GHz (9.2––18 GHz).

Iron‐catalyzed, elemental selenium‐promoted cyclization of 2‐nitrobenzonitriles with arylacetic acids

AbstractWe report herein a method for synthesis of 2‐arylquinazolin‐4(3H)‐ones via an iron‐catalyzed, elemental selenium‐promoted cascade annulation of 2‐nitrobenzonitriles with arylacetic acids. The reactions proceeded in the presence of iron(III) acetylacetonate catalyst, elemental selenium, and DABCO base. A wide range of functionalities, including unprotected alcohols, amines, methylsulfonyl, and halogen groups, were compatible with reaction conditions.

Scalable Synthesis of Stable Electrocatalyst for Oxygen Reduction Reaction

Carbon-based materials have been widely recognized as support material of choice for the oxygen reduction reaction due to their intriguing properties, such as high electrical conductivity, structural flexibility, and low cost. Platinum and its alloys supported on carbon are currently considered the benchmark catalysts for the oxygen reduction reaction (ORR) in Proton Exchange Membrane Fuel Cells (PEMFCs). Confining platinum within the pore system of mesoporous carbon prepared by hard-templating has proven to be an effective way to mitigate catalyst degradation in PEMFCs.[1] However, the challenge of template removal and the limited yield have hindered its practical application in industry. As a remedy, we establish a simple synthesis of carbon gels through sol-gel polymerization of resorcinol (R) and formaldehyde (F), ultimately resulting in graphitic mesoporous carbons.The synthesis process involves mixing resorcinol and formaldehyde in the presence of a basic catalyst, followed by heating for a certain period of time to obtain crosslinked gels.[2] Specific metal salts can be incorporated into the reaction to synthesize mesoporous and highly graphitic carbon spheres (GRF-Sphere) in a straightforward manner, without the need for hydrothermal steps, solvent exchanges, supercritical drying, or post-activation techniques. While conventional carbonized RF spheres are typically non-graphitic and microporous (Fig. 1.), modification of the synthesis route allows for the production of mesoporous, highly graphitic carbon spheres (GRF-Sphere) by taking advantage of the porogenic and graphitization effect of Fe(acac)2. Platinum nanoparticles with an average size of ca. 3 nm were deposited into the pores of GRF-spheres by incipient wetness impregnation followed by annealing at 750 °C. The specific activity of the Pt/GRF-Sphere catalyst for the ORR was found to be greater than 0.45 mA cm-2 Pt at 0.9 V vs. RHE, which in comparison with the literature indicates high catalytic activity.[3] The confinement of the active phase within the pores of the GRF-Spheres contributed to enhancing the stability of the catalyst, as confirmed by an accelerated stress test performed within the typical operating range of a PEMFC (0.6 - 1.0 VRHE). The Pt/GRF-Sphere was found to retain a significantly higher proportion of active surface area when compared to a reference Pt/Vulcan catalyst with similar platinum particle size (Fig. 1.).Furthermore, increasing the concentrations of resorcinol and formaldehyde by 25-fold resulted in the synthesis of a mesoporous and highly graphitic gel, namely GRF-Gel, at a substantial volume yield of70 g L-1, which underlines the potential for this process to be scaled up for industrial application. The ORR activity and stability of GRF-Gel in RDE are currently being investigated. Moreover, the electrochemical performance of this material will be evaluated in a single-cell PEMFC in collaboration with the group of Prof. Hubert Gasteiger (TU Munich).Overall, this research provides a promising and straightforward approach to synthesize highly graphitic mesoporous carbon materials using iron acetylacetonate as a porogen and graphitization catalyst. The method is based on the established preparation of RF-gels but includes iron salts. We have demonstrated that Pt/GRF-Sphere, which is produced by depositing Pt nanoparticles into the pore system of the GRF-Sphere, exhibits high activity and stability for the ORR. Given the simplicity and scalability of our synthesis procedure and the tailored morphology of these carbon materials, we believe that Pt/GRF-Sphere and Pt/GRF-Gel have great potential for industrial applications. Acknowledgement: We acknowledge the financial support from the German Federal Ministry for Economic Affairs and Energy (BMWi) in the framework of POREForm (project number 03ETB027F).

Iron(III) promoted oxidative annulation of benzylic C-H bonds in (α-amino)arylacetic acids for synthesis of 4-aryl pyrrolo[1,2-a]quinoxalines

Using amino acids for synthesis of heterocycles is a synthetically promising field. However, developing the practical methods for transformations of amino acids into heterocycles is still challenging. Given that alpha amino acids are abundant or easily prepared, herein we report a method for annulation of benzylic C-H bonds in derivatives of 2-phenylglycine with 1-(2-nitroaryl)pyrroles. The reactions proceeded well in the presence of iron(III) acetylacetonate catalyst and potassium carbonate base. Scope of pyrrolo[1,2-a]quinoxalines was studied. Regardless of electronic properties of substituents, the pyrrolo[1,2-a]quinoxaline de-rivatives were successfully isolated, as yields varied from 42% to 52%. Pyrrolo[1,2-a]quinoxalines substituted with heterocycles at C4 positions as pyridine and thiophene were competent substrates. Reaction mechanism was proposed to start with a decar-boxylative/deaminative sequence of 2-phenylglycine to afford benzaldehyde. The iron catalyst was presumed to facilitate the re-duction of 1-(2-nitroaryl)pyrroles to furnish the corresponding aniline. Imine condensation followed by cyclisation and oxidation would yield the pyrrolo[1,2-a]quinoxaline. Our method would offer a convenient tactic to transform abundant alpha amino acids into synthetically useful heterocycles.

Chemical reaction and phase transformation mechanism of electrospun iron (III) acetylacetonate-polyacrylonitrile fibers during pre-oxidation process

Low-temperature pre-oxidation of electrospun metal-compound-incorporated carbon fibers can involve phase transitions and chemical reactions. However, their mechanics remain unclear. In this work, a mixture of polyacrylonitrile (PAN) and iron acetylacetonate is subjected to electrospinning followed by a pre-oxidation process at 230 °C, producing PAN fibers loaded with iron compounds. Our detailed investigations shed light on the mechanisms of phase transitions and associated chemical reactions during the pre-oxidation process. Our findings reveal that PAN undergoes cyclization during pre-oxidation, and that crystalline iron acetylacetonate within PAN fibers transforms into amorphous FeO and Fe2O3.

Flexible electrospun iron/manganese-based compounds/carbon fibers: Phase transformation and electrochemical properties

Iron compounds have been extensively used as anode materials of lithium-ion batteries because of their low-cost and excellent electrochemical performance. However, iron compounds have a poor cyclic stability as a result of their drastic volume change in the charge/discharge processes. Herein, we propose an effective strategy to improve the cyclic performance of iron compounds by carbon coating and mixing with manganese oxide. To implement this, flexible carbon fibers embedded with Fe/Mn-based nanoparticles are produced by electrospinning with subsequent annealing process. By adjusting the annealing temperatures, the phase transformation of Fe/Mn-based compounds within carbon fibers is investigated in details. As the annealing temperature increases, Fe/Mn precursors (iron acetylacetonate and manganese acetylacetonate) in the fibers decompose gradually and then Fe3O4 and MnO nanoparticles form successively. When the temperature rises to 800 °C, the formed Fe3O4 is gradually reduced by carbon to produce Fe3C while MnO remains unchanged. The carbon fibers loaded with different Fe/Mn-based compounds (Fe3O4, Fe3O4/MnO, Fe3O4/Fe3C/MnO and Fe3C/MnO) are obtained under different annealing temperatures. Among these composites, carbon fibers loaded with Fe3O4/Fe3C/MnO nanoparticles exhibit the best specific capacity (750.23 mAh g−1 after 250 cycles) and cyclic stability, ascribing to the synergistic effect of iron and manganese compounds. Furthermore, it is found that charge transfer impedance of the anodes is reduced and Li+ diffusion ability is improved as the annealing temperature increases, which is ascribed to the increasing content of Fe3C and the short Li+ diffusion distance resulted from the reduced diameter of carbon fibers. The excellent electrochemical performance indicates that the hybrid electrospun nanofibers have a great potential application for flexible lithium-ion batteries.

Preparation and Characterization of Corn Straw-Based Graphitized Carbon with Ferric Acetylacetonate as Catalyst

Graphitized carbon exhibits exceptional thermal stability, electrical conductivity, corrosion resistance, and various intricate physical and chemical properties. Consequently, it has found extensive applications in diverse fields, such as electrodes, refractory materials, nuclear reactors, and supercapacitors. However, natural graphite is a limited nonrenewable resource, so finding other materials, exploring reliable graphitization methods, and achieving efficient green graphite production as an essential trend in the future is essential. In this paper, with corn straw liquefied product (CSLP) as raw material, ferric acetone catalyst, using carbonization, catalytic graphitization preparation of corn straw based graphitic carbon (CSBGC). When the graphitization temperature was 850 °C and the amount of ferric acetylpropionate (Fe(acac)3) was 7.0 mmol/g, the graphitized carbon showed better graphitization, micro fragmentation structure, and more minor defects, which effectively reduced the graphitization temperature, and the graphitic carbon rate of corn straw (CS) reached 25.2%. This study not only presents a highly efficient approach for synthesizing superior biomass-derived graphite carbon but also introduces usable perspectives on using corn straws.

Magnetic behavior of in-situ synthesized iron oxides in mesoporous graphite matrix

Microwave irradiation-induced synthesis of nanomaterials offers large-scale fabrication by in-situ decomposition of organo-metallic complexes through a variety of solvents. But there are limited attempts to fabricate them using a solvent-free environment. In the present work, we have reported successfully pyrolysis of ferric acetylacetonate complex to produce iron oxide using mesoporous graphite (MG) under microwave irradiation without assistance of solvent. The two-step synthesis consists of the preparation of mesoporous graphite using mild conditions of Hummer’s method and its composite with ferric oxides was done by heating mesoporous graphite with ferric acetylacetonate in a domestic microwave oven. The preliminary magnetic behavior of in-situ synthesized mesoporous graphite (MG) composite with mixed ferric oxides was studied. The room temperature magnetic behavior of the as-prepared composite exhibited saturation magnetization of 11.27 emu-g-1. The Formation of α-Fe2O3 and γ-Fe2O3 along with particle size distribution and dispersion was evaluated through detailed structural characterization. Our study shows mesoporous graphite acts not only as a substrate but also as a microwave receptor. This can extend the avenues of existing carbonaceous materials in converting microwave energy into thermal energy.

CRGD-Conjugated GdIO Nanoclusters for the Theranostics of Pancreatic Cancer through the Combination of T1-T2 Dual-Modal MRI and DTX Delivery.

Clinically, magnetic resonance imaging (MRI) often uses contrast agents (CAs) to improve image contrast, but single-signal MRI CAs are often susceptible to calcification, hemorrhage, and magnetic sensitivity. Herein, iron acetylacetone and gadolinium acetylacetone were used as raw materials to synthesize a T1-T2 dual-mode imaging gadolinium-doped iron oxide (GdIO) nanocluster. Moreover, to endow the nanoclusters with targeting properties and achieve antitumor effects, the cyclic Arg-Gly-Asp (cRGD) peptide and docetaxel (DTX) were attached to the nanocluster surface, and the efficacy of the decorated nanoclusters against pancreatic cancer was evaluated. The final synthesized material cRGD-GdIO-DTX actively targeted αvβ3 on the surface of Panc-1 pancreatic cancer cells. Compared with conventional passive targeting, the enrichment of cRGD-GdIO-DTX in tumor tissues improved, and the diagnostic accuracy was significantly enhanced. Moreover, the acidic tumor microenvironment triggered the release of DTX from cRGD-GdIO-DTX, thus achieving tumor treatment. The inhibition of the proliferation of SW1990 and Panc-1 pancreatic cancer cells by cRGD-GdIO-DTX was much stronger than that by the untargeted GdIO-DTX and free DTX in vitro. In addition, in a human pancreatic cancer xenograft model, cRGD-GdIO-DTX considerably slowed tumor development and demonstrated excellent magnetic resonance enhancement. Our results suggest that cRGD-GdIO-DTX has potential applications for the precise diagnosis and efficient treatment of pancreatic cancer.

Effect of dopant on the thermal stability of core-shell ferrite nanoparticles

In this study, a series of core–shell ferrite nanoparticles were obtained by the thermal decomposition method of iron(III) acetylacetonate. Various amounts of Co3+, Mn3+, or Ni2+ ions as dopants were used. The prepared nanoparticles were treated at 500 °C for 24 h in the air atmosphere to determine the influence of doping on magnetite/maghemite crystalline structure and the following oxidation process. The nanoparticles before and after thermal treatment were evaluated by transmission electron microscopy, energy dispersive X-ray, X-ray diffraction and Mössbauer spectroscopy. The conducted studies show that doping primary structures by different 3d elements modulates the oxidation process of ferrite nanoparticles which, therefore, gives new possibilities for their application. However, the resistance to the oxidation of layered particles is different in comparison to the one-pot synthesis procedure. The susceptibility to oxidation varies not only due to the presence of different dopants in variable concentrations, but it also is dependent on layer positioning in the particle (core, shell, or both). The most protective element is Mn, and the least one – Co.

Influence of long-term thermal treatment of magnetite nanoparticles on its physicochemical properties

In the presented paper, a long term thermal treatment at 50 °C was performed on four types of magnetite nanoparticles to observe if there is a transformation induced to other iron oxides. Such information is critical when hyperthermia application is foreseen due to different magnetic properties of Fe3O4, γ-Fe2O3 and α-Fe2O3. Nanoparticles were obtained by co-precipitation of iron (II) and (III) chlorides or by thermal decomposition of iron (III) acetylacetonate. Both types of nanoparticles were covered with a protective silver shell to increase their oxidative stability. The experiment was conducted in phases over the course of 28 days. Characterization of thermally treated nanoparticles was performed by transmission electron microscopy, x-ray diffraction, infrared spectroscopy and Mössbauer spectroscopy. According to the obtained results, nanoparticles synthesized by co-precipitation of iron chlorides are less thermally stable than those obtained by thermal decomposition. However, both types of nanoparticles do not oxidize to hematite even when exposed to long-term (up to 28 days) gentle (below 50 °C) heating.

Solubility of iron(III) and nickel(II) acetylacetonates in supercritical carbon dioxide

As a common precursor for supercritical CO2 (scCO2) deposition techniques, solubility data of organometallic complexes in scCO2 is crucial for the preparation of nanocomposites. Recently, metal acetylacetonates have shown great potential for the preparation of single-atom catalytic materials. In this study, the solubilities of iron(III) acetylacetonate (Fe(acac)3) and nickel(II) acetylacetonate (Ni(acac)2) were measured at the temperature from 313.15 to 333.15 K and in the pressure range of 9.5–25.2 MPa to accumulate new solubility data. Solubility was measured using a static weight loss method. The semi-empirical models proposed by Chrastil and Sung et al. were used to correlate the solubility data of Fe(acac)3 and Ni(acac)2. The equations obtained can be used to predict the solubility of the same system in the experimental range.