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Investigation of CeO2, MoO3, and Ce2(MoO4)3, Synthesized by the Pechini Method, as Catalysts for Fructose Conversion

Group of Catalysis and Chemical Reactivity, Institute of Chemistry and Biotechnology, Federal University of Alagoas, Av. Lourival Melo Mota, Tabuleiro do Martins, Maceió 57072-970, AL, Brazil
Author to whom correspondence should be addressed.
Catalysts 2023, 13(1), 4;
Received: 9 November 2022 / Revised: 14 December 2022 / Accepted: 16 December 2022 / Published: 20 December 2022


Cerium oxide (Ce100), molybdenum oxide (Mo100), and a material containing Ce and Mo (CeMo) were synthesized by the Pechini method, using glycerol as a polyol. These materials were applied for fructose conversion in an aqueous medium. The characterization results show the formation of cerium molybdate (Ce2(MoO4)3) for CeMo. Ce100 presented good thermal stability, and Mo100 sublimation of MoO3 and polymolybdates was verified. CeMo exhibited a mass loss of 19%, associated with the sublimation of MoO3 and polymolybdate species. Additionally, the existence of Bronsted and Lewis acid sites was confirmed, and the addition of Mo to Ce was an efficient strategy to increase the acidity. Regarding the catalytic activity (150 °C and 0.5 to 6 h), Ce100 exhibited low conversions and high selectivity to 5-hydroxymethylfurfural (5-HMF). For Mo100, high conversions, with a significant formation of insoluble materials, were detected. For CeMo, beyond the high activity, a lower formation of insoluble materials was noted. In this case, selectivity toward products from the retro–aldolic route and 5-HMF were obtained. These results indicate that the main factor influencing fructose conversion is an adequate combination of the acid sites. Recycling experiments were carried out, and stability was observed for four cycles, confirming the robustness of this system.

Graphical Abstract

1. Introduction

The environmental and social problems caused by the dependence of the global energy matrix and the chemical synthesis on fossil fuels (oil, coal, and natural gas) motivated the search for sustainable energy sources, with an emphasis on biomass [1,2,3]. Regarding biomass-derived inputs, special attention is directed to carbohydrates, such as fructose, since the conversion of these molecules provides the formation of a spectrum of valuable chemicals [4], including 5-hydroxymethylfurfural [5] and lactic acid [6].
Catalysis is strategic in the transformation of biomass, mainly because it influences the selectivity to the desired product and thus minimizes the generation of byproducts. The development of heterogeneous catalysts is a key resource for sustainable advancement due to its associated advantages, such as easy recovery and reuse. From this perspective, metal oxides have been widely explored due to their acid/base and redox characteristics, as well as the presence of structural defects. These parameters are very important for academic and industrial applications; moreover, these materials are affordable [3,7,8,9,10,11,12].
The unique properties of cerium- and molybdenum-based materials justify their various catalytic applications. Cerium oxide exhibits outstanding physical and chemical stability, ease of reduction or oxidation (Ce3+ ↔ Ce4+), and high electron mobility in the crystal lattice [8,13,14]. Molybdenum oxide is known to be an efficient modulator of acidity [15]. The presence of Lewis and Bronsted acid sites directly influences the conversion of carbohydrates [11].
The junction of metal oxides can lead to attractive changes in physical, chemical, and catalytic properties [8]. This fact allows for the development in this study of a promising catalytic system using cerium and molybdenum for carbohydrate conversion. Although the application of cerium molybdate—exhibiting contributions in photocatalysis [16], gas detection [12], antiviral activity [17], and catalysis [18]—in diverse areas is extensive, to date, no information has been found on its evaluation in the conversion of hexoses. Several synthesis routes, including the precipitation method [19], wet impregnation [15,20], and hydrothermal methods [21], can be used for the preparation of metal oxides. However, the Pechini method has been noted as one of the most promising methodologies for obtaining heterogeneous catalysts because it requires low cost and the use of mild temperatures, as well as being considered a simple process [22]. The basic procedure of the synthesis consists of the formation of a polymeric resin in which the cations are homogeneously dispersed through a reaction between a polycarboxylic acid (such as citric acid), metal ions, and a polyol [23,24,25,26]. Ethylene glycol is commonly used as a polymerizing agent in the Pechini method [22,27]. However, this compound presents toxicity and is generated largely by fossil fuel sources [28,29]. On the other hand, glycerol is a nontoxic product, and it can be obtained renewably; a possible replacement of polyol may assign a more sustainable footprint to this route [24,30,31].
Therefore, this study proposed to synthesize cerium oxide (CeO2), molybdenum oxide (MoO3), and a mixed oxide based on Mo and Ce through the modified Pechini method, using glycerol as a polymerizing agent. For the first time, such materials, after characterization, were evaluated in the conversion of fructose to chemical inputs of industrial interest.

2. Results and Discussion

The catalysts Ce100, Mo100, and Ce Mo were used in the conversion of fructose in an aqueous medium, and the results are shown in Figure 1. Initially, the experiments showed that Ce100 leads to low conversions, comparable to those obtained in the reaction carried out without the addition of a catalyst. However, in the presence of Mo100 and CeMo, higher conversions were observed, especially for Mo100. For example, at 3 h of reaction, the observed values of conversion were 97.4 and 91.8% for Mo100 and CeMo, respectively. After 4 h of reaction, the two systems led to very close conversions, and the system tended to reach equilibrium.
Such conversions may be related to the properties of these catalytic systems, and Table 1 presents some results regarding the characterization and evaluation of the acid sites.
The low conversion obtained in the presence of Ce100 can be explained by the fact that, even with a surface area much larger than that observed for the other systems investigated here, there is a smaller number of Bronsted and Lewis acid sites in the structure of this material. In the case of the other two systems, higher numbers of acid sites were observed, which justifies the higher conversions, despite the low surface areas. Furthermore, it is important to note that in the CeMo catalyst, the AB/AL ratio is superior to the other pure oxides, indicating a higher incidence of Bronsted acid sites in this material.
Previous study data indicate that the number of Lewis and Bronsted acid sites available in the catalyst is related to the success of this type of conversion, and the synergism resulting from the combination between these sites is responsible for obtaining promising results in terms of converting carbohydrates into molecules of interest [8,32,33]. For example, in the synthesis of the mixed oxides of molybdenum and tin, increasing the content of molybdenum in relation to tin increases the acidity, leading to high fructose conversions, with selectivity to the products obtained by retro-aldol and dehydration reactions [11].
Regarding the soluble products identified (see Figure 2) in the presence of Mo100, there is no defined selectivity, although in the first few hours of reaction, this system is the most active of all. In contrast, in the presence of Ce100, a great selectivity to HMF and to products and intermediates of the retro–aldol pathway is observed (glyceraldehyde, dihydroxyacetone, pyruvaldehyde, and lactic acid). However, the latter showed maximum conversions of 50% between 5 and 6 h of reaction. For CeMo, a change in the selectivity profile is observed, with a majority targeting the retro–aldol pathways (pyruvaldehyde, glyceraldehyde, lactic acid, and acetic acid), isomerization (glucose), and dehydration (5-HMF).
The formation of 5-HMF follows the route of dehydration of the fructose molecule, which occurs through the consecutive loss of three water molecules. However, due to the high instability of 5-HMF in aqueous media, organic acids are formed, as well as humins [34,35]. The Ce100 catalyst showed high selectivity (70.2% at 6 h) for 5-HMF. On the other hand, the Mo100 and CeMo systems exhibited lower selectivity for this product under the same conditions, 14.5% and 27.5%, respectively. This fact can be explained by the formation of organic acids (levulinic and formic) through the hydration of 5-HMF [34]. It should be noted that for Ce100, no levulinic or formic acid was identified, and this fact can be associated with the nature of the acid sites associated with this catalyst [36]. The literature reports that the decomposition of 5-HMF into organic acids and other side reactions are favored when there are higher numbers of acidic sites in the catalyst [11,37,38]. As shown in Table 2, CeMo and Mo100 contain more of these sites when compared to Ce100. However, for Ce100 and CeMo, the increase in fructose conversion implies an increase in 5-HMF selectivity, a characteristic that is not observed for Mo100.
The reduced selectivity to 5-HMF, mainly with the use of Mo100 (14.5%) and CeMo (27.5%) compared to Ce100 (70.2%), may also be associated with the formation of humins, promoted by the condensation between 5-HMF and other reaction intermediates and which is closely related to the conditions used and the acidity of the catalyst [36,39]. The presence of this byproduct can be quantitatively identified through the color change of the reaction medium, that is, the evolution to a dark brown color [36]. As shown in Figure 3, there was a greater formation of humins for Mo100 due to the high acidity of the material (Table 2). For CeMo, a lower and adequate acidity inhibited the high generation of these byproducts. The same justification can be used for Ce100; however, the lower number of acid sites also directly influenced the catalyst activity (see Figure 1). Such observations suggest that a possible structural change, in relation to the pure oxides, obtained in the case of CeMo leads to a better conversion of fructose, maintaining the advantage in terms of the formation of a smaller amount of insoluble products when compared to Mo100.
Lactic acid is a product widely used in the food, chemical, pharmaceutical, and cosmetics industries [40]. When using CeMo and Ce100, a high selectivity was observed for pyruvaldehyde (lactic acid precursor) in the initial reaction times up to 2 h. With longer reaction times, the selectivity to pyruvaldehyde decreases as lactic acid is formed. Interestingly, for Ce100, the presence of glyceraldehyde is notable at lower levels than those of the other precursors, suggesting that the conversion reaction of the product to pyruvaldehyde is very rapid [41]. Previous studies report that the Bronsted and Lewis acid sites are fundamental in promoting the formation of lactic acid, with the first acting on the dehydration of triose to pyruvaldehyde and the second promoting the conversion of pyruvaldehyde to lactic acid through the 1,2 displacement of hydride [42,43].
As shown in Figure 2, Mo100 showed greater selectivity for lactic acid and its intermediates due to the greater number of Lewis acid sites in its structure, which enabled the conversion of pyruvaldehyde. Similarly, this explanation is also useful in relation to the greater selectivity of CeMo to lactic acid when compared to Ce100. This suggests that the lower Lewis acidity and considerable number of Bronsted acid sites present in CeMo and Ce100 led to higher selectivities to pyruvaldehyde in the initial reaction times.
Acetic acid is one of the products in high demand in the chemical industry, and it is used as a precursor for various chemical compounds [44,45]. Its most common formation route from the biomass is the retro–aldolic pathway [11,24]. When Ce100 was used as a catalyst, the presence of this compound was not observed, since the decomposition route for the formation of acetic acid is directed by the Lewis acid sites, which were also not identified when Ce100 was used [46]. Furthermore, a greater selectivity of CeMo (29.9%) to acetic acid was observed in relation to Mo100 (18.8%) at 6 h. This result suggests a greater suitability of sites in CeMo, while the greater acidity of Mo100 led to other parallel reactions.
The characterization of these materials, obtained through the Pechini method by using glycerol instead of ethylene glycol, by XRD revealed that cerium molybdate (Ce2(MoO4)3) was formed in the case of the CeMo material (Figure 4), and no signals referring to the individual oxides were identified. The formation of (Ce2(MoO4)3) was confirmed by the crystalline planes assigned to the reflection lines (002) (100) (101) (112) (004) (200) (211) (204) (220) (116) (312) (224) (card # 30–0303) [17]. As shown in Figure 4, Ce100 exhibits a fluorite-like (CaF2) face-centered cubic structure, according to the JCPDS crystallographic sheet No. 34-0394 [8,13,21]. Mo100 showed all peaks perfectly indexed, suggesting the formation of the orthorhombic phase (JCPDS No. 05-0508).
Based on the information extracted from the diffractograms, the crystallite size (see Table 1) was calculated using the Debye–Scherrer equation, and for this, the most intense diffraction peaks of CeMo, Ce100, and Mo100 were used, e.g., (112), (040), and (111), respectively. Therefore, the diffractograms show that the addition of molybdenum leads to an increase in crystallite size, suggesting crystal growth by particle aggregation because of mixed oxide formation [15]. This fact also corroborates the result obtained by the BET method, from which a pronounced reduction in the specific surface area was observed (see Table 1).
The structural changes that occurred by the formation of Ce2(MoO4)3, in relation to the individual oxides, were confirmed by the evaluation of thermal behavior. In the thermogram obtained for CeMo (Table 2 and Figure S1, Supplementary Materials), only one thermal decomposition event was observed above 1000 °C (with a mass loss of 19%), which clearly continues to occur, but which is not quantified due to the limitation of the equipment, which operates at a maximum temperature of 1500 °C. This suggests that the interaction between the molybdenum and cerium ions for the formation of cerium molybdate leads to an increase in thermal stability, and the mass loss above 850 °C is associated with the decomposition of the material into cerium and molybdenum oxide and the subsequent sublimation of MoO3 [47,48,49]. Reports indicate that in this type of material, when subjected to temperatures above 700 °C, defects are formed that favor greater mobility of the molybdenum and cerium ions, consequently leading to changes in the mutual interaction between them, leading to increased thermal stability [48].
Three thermal decomposition events were observed in Ce100 (Figure S1, Supplementary Materials). The first event (mass loss of 2.3%) is attributed to the desorption of water molecules (Khalil et al., 2005). The second event starts at 730 °C (mass loss of 2.7%) and can be related to the oxygen output from the oxide structure [50,51]. The total mass loss recorded after heating from 25 °C to 1500 °C was 7.4%, suggesting good thermal stability. In the case of Mo100 (see Figure S1, Supplementary Materials), two thermal decomposition events were observed. The first, which occurs in the range of 700–850 °C (mass loss of 78.2%), corresponds to the sublimation of MoO3. The second occurs between 850–1000 °C (mass loss of 17.5%) and can be associated with the output of polymolybdates [11].
Therefore, it can be inferred that the synthesis of the material from the molybdenum and cerium precursors, under the conditions used here, is an efficient strategy for the modulation of acid sites, resulting in a suitable catalytic system for the conversion of fructose into an aqueous medium. The formation of insoluble byproducts is minimized when compared to Mo100, leading to promising conversions, mainly after 3 h of reaction under the conditions investigated here. In addition, a superior thermal stability of CeMo was observed in relation to Mo100.
Catalyst recyclability is of great importance in biorefinery processes [11]. In this study, the catalyst was calcined to eliminate organic fractions and perform reuse tests (1 h, 1.5 × 103 g of catalyst, 150 °C). The results of the recycling experiments are shown in Figure 5, and only a small variation in conversion and selectivity values was observed for CeMo for each of the 4 cycles tested (approximately 72.0% of conversion, on average). The liquid samples collected after the first and the last (4th) cycle were subjected to X-ray dispersive energy spectrometry (EDX) analysis, and no significant amount of molybdenum or cerium was detected, suggesting that leaching did not occur.

3. Materials and Methods

3.1. Materials

Ammonium heptamolybdate tetrahydrate (99.9%, Sigma-Aldrich, St. Louis, MI, USA), cerium(III) nitrate hexahydrate (99.9%, Sigma-Aldrich), citric acid (>99.0%, Sigma-Aldrich), ammonium hydroxide (Sigma-Aldrich), nitric acid (>65.0%, Sigma-Aldrich), glycerol (>99.0%, Sigma-Aldrich), and fructose (>99.0%, Sigma-Aldrich) were obtained commercially and used as received.

3.2. Synthesis and Characterization

Initially, citric acid and the metal precursor were weighed in a molar ratio of 3:1. Then, both were dissolved separately in deionized water at 30 °C under constant stirring and mixed for 30 min. The next step was the addition of glycerol to the prepared solution in a molar ratio of 60:40, based on the amount of citric acid, maintaining vigorous stirring at 70 °C for 3 h to ensure the homogeneity of the system. Subsequently, the temperature was increased to 130 °C to promote the polyesterification reaction and the subsequent formation of the polymeric resin. The metal precursors used were cerium(III) nitrate hexahydrate and ammonium heptamolybdate [24,31]. The mixed catalyst was prepared in a mass ratio of 75% cerium to 25% molybdenum, and cerium(III) nitrate hexahydrate and ammonium heptamolybdate were weighed and dissolved separately in deionized water at 30 °C under constant stirring. Soon after, both were mixed and added to a beaker containing a solution of citric acid, maintained under vigorous stirring for 30 min. All the following procedures were identical to those described above for the pure oxides. The materials were subjected to heat treatment at 280 °C for 2 h, using a heating rate of 10 °C/min to break the polymer chains and form a semicarbonized black powder. Subsequently, they were macerated in a mortar and sieved (100 mesh) to be placed again in the muffle furnace at 550 °C for 4 h. Finally, all materials were stored under an argon atmosphere. Table 3 presents the description of the catalysts and the codes used.
For material characterization, X-ray diffraction (XRD) measurements were performed using a Shimadzu diffractometer, model XRD-6000, and a Cu Kα radiation source (1.5418 Å) with a nickel filter to obtain wide-angle diffraction patterns in the 2θ = 3–40° range. Crystallite size (nm) was calculated using the Debye–Scherrer equation.
Nitrogen adsorption measurements were performed at 77.15 K using a gas adsorption analyzer (Micromeritics, model ASAP-2020). The textural properties were estimated from the N2 adsorption isotherms using the Brunauer–Emmett–Teller (BET) equation and the Barrett–Joyner–Halenda (BJH) method. Before the analysis, all the samples were pretreated under vacuum at 423.15 K for 24 h. Thermogravimetric (TG/DTG) analyses were performed using a Shimadzu analyzer, model DTG-60H, with an N2 flow rate of 40 mL·min1 in the temperature range of 30–800 °C at a heating rate of 10 °C·min1. Fourier transform infrared (FTIR) spectra were obtained with a Shimadzu IR Prestige 21 infrared spectrophotometer using potassium bromide tablets (KBr). A total of 80 scans were performed in the transmittance mode in the spectral range of 4000–400 cm1 at a resolution of 4.0 cm1.

3.3. Conversion of Fructose

All experiments were performed in 4 mL vials under magnetic stirring and heating (150 °C), at several reaction times. The fructose solution was 0.016 g of fructose in 2 mL of deionized water, and for some experiments, catalysts (1.5 × 10−3 g) were used. Conversion, yield, and selectivity were calculated from the results of quantification by HPLC. The reuse tests of CeMo (G) were carried out at 150 °C for 2 h under the same reaction conditions. Subsequently, the catalyst was removed from the reaction medium by centrifugation and calcined at 550 °C for 4 h for subsequent reuse. The liquid samples collected after the cycles were subjected to X-ray dispersive energy spectrometry (EDX) analysis to determine whether leaching had occurred.

4. Conclusions

In the absence of a catalyst or using Ce100, low fructose conversions were observed, with the formation mainly of 5-HMF. In contrast, in the presence of Mo100 and CeMo, higher conversions are achieved, and the formation of different products was observed. However, using Mo100, which exhibits a higher number of Lewis and Bronsted acid sites than does CeMo, higher conversions were observed before the achievement of thermodynamic equilibrium, but this is accompanied by the formation of a greater amount of soluble and insoluble material, directly reflected in the color evolution of the reactions over time. In relation to the soluble products formed from fructose using CeMo, the direction to the retro–aldolic pathway was observed, evidencing the modulation of these systems. It is important to highlight that the low conversion obtained in the presence of Ce100 can be explained by the smaller number of Brostend and Lewis acid sites in the structure of this material, even with a surface area much higher than that observed for the other systems. In the case of Mo100 and CeMo, higher levels of acid sites were observed, which justifies the higher conversions, despite the low surface areas. Reuse and leaching tests indicated that the CeMo system proved to be stable and robust under the conditions tested.

Supplementary Materials

The following supporting information can be downloaded at:, Figure S1: Thermogravimetric analysis (TG/DTG): (A) Ce100, (B) Mo100, and (C) CeMo.

Author Contributions

Conceptualization, D.B.d.A.P., M.R.M. and S.M.P.M.; methodology, D.B.d.A.P., T.V.d.S.M., J.A.d.V.J. and D.O.d.S.A.; investigation, D.B.d.A.P., T.V.d.S.M., J.A.d.V.J., M.R.M. and S.M.P.M.; resources, M.R.M. and S.M.P.M.; writing—original draft preparation, D.B.d.A.P., T.V.d.S.M. and S.M.P.M.; writing—review and editing, D.B.d.A.P., T.V.d.S.M., M.R.M. and S.M.P.M.; visualization, D.B.d.A.P., T.V.d.S.M., J.A.d.V.J., M.R.M. and S.M.P.M.; supervision, M.R.M. and S.M.P.M.; project administration, M.R.M. and S.M.P.M.; funding acquisition, M.R.M. and S.M.P.M. All authors have read and agreed to the published version of the manuscript.


This research was supported by the National Council for Scientific and Technological Development (CNPq), the Brazilian Federal Agency for the Improvement of Higher Education (CAPES), the Brazilian Innovation Agency (FINEP), and the Alagoas Research Foundation (FAPEAL). G.C.A. and I.M.A.S. express their appreciation for fellowships granted by CAPES and CNPq. M.R.M. and S.M.P.M. thank CNPq for research fellowships.

Data Availability Statement

Not applicable.


The authors also thank the LSCAT/CTEC/UFAL, TecNano/ICF/UFAL, and GON/IF/UFAL teams for their contributions.

Conflicts of Interest

The authors declare no conflict of interest.


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Figure 1. Fructose conversion at 150 °C without a catalyst or with 1.5 × 10−3 g of Ce100, Mo100, or CeMo.
Figure 1. Fructose conversion at 150 °C without a catalyst or with 1.5 × 10−3 g of Ce100, Mo100, or CeMo.
Catalysts 13 00004 g001
Figure 2. Visual aspects of the samples during the reaction, using catalysts (1.5 × 103 g) at 150 °C (0.5 to 6 h).
Figure 2. Visual aspects of the samples during the reaction, using catalysts (1.5 × 103 g) at 150 °C (0.5 to 6 h).
Catalysts 13 00004 g002
Figure 3. Selectivity for soluble products identified in the fructose conversion at 150 °C, without a catalyst and with 1.5 × 103 g of Ce100, Mo100, and CeMo.
Figure 3. Selectivity for soluble products identified in the fructose conversion at 150 °C, without a catalyst and with 1.5 × 103 g of Ce100, Mo100, and CeMo.
Catalysts 13 00004 g003
Figure 4. XRD patterns of Ce100 (Catalysts 13 00004 i001 = fluorite-like face-centered cubic structure (JCPDS 34-0394)), Mo100 (* = orthorhombic phase (JCPDS No. 05-0508)), and CeMo (Catalysts 13 00004 i002 = Ce2(MoO4)3 (JCPDS 30–0303).
Figure 4. XRD patterns of Ce100 (Catalysts 13 00004 i001 = fluorite-like face-centered cubic structure (JCPDS 34-0394)), Mo100 (* = orthorhombic phase (JCPDS No. 05-0508)), and CeMo (Catalysts 13 00004 i002 = Ce2(MoO4)3 (JCPDS 30–0303).
Catalysts 13 00004 g004
Figure 5. Results of reuse for the CeMo system (150 °C, 1 h).
Figure 5. Results of reuse for the CeMo system (150 °C, 1 h).
Catalysts 13 00004 g005
Table 1. Textural and structural properties of the solids investigated in this study.
Table 1. Textural and structural properties of the solids investigated in this study.
SampleSBET a
Crystallite Size
(nm) b
Bronsted c
Lewis c
a SBET, specific surface area, calculated by the BET equation. b Crystallite size (nm) calculated by the Debye–Scherrer equation. c Number of Lewis and Bronsted acid sites (mmol·g−1), obtained from FTIR spectra using pyridine as the probe molecule. d Ratio of the number of Lewis and Bronsted acid sites.
Table 2. Ranges of thermal decomposition for Ce100, Mo100, and CeMo.
Table 2. Ranges of thermal decomposition for Ce100, Mo100, and CeMo.
T (°C)
nd = not detected.
Table 3. Code of the catalysts and the respective descriptions.
Table 3. Code of the catalysts and the respective descriptions.
Ce100Cerium oxide(IV) (CeO2)
Mo100Molybdenum oxide(VI) (MoO3)
CeMoCerium molybdate (Ce2(MoO4)3)
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MDPI and ACS Style

Pryston, D.B.d.A.; Martins, T.V.d.S.; Vasconcelos Júnior, J.A.d.; Avelino, D.O.d.S.; Meneghetti, M.R.; Meneghetti, S.M.P. Investigation of CeO2, MoO3, and Ce2(MoO4)3, Synthesized by the Pechini Method, as Catalysts for Fructose Conversion. Catalysts 2023, 13, 4.

AMA Style

Pryston DBdA, Martins TVdS, Vasconcelos Júnior JAd, Avelino DOdS, Meneghetti MR, Meneghetti SMP. Investigation of CeO2, MoO3, and Ce2(MoO4)3, Synthesized by the Pechini Method, as Catalysts for Fructose Conversion. Catalysts. 2023; 13(1):4.

Chicago/Turabian Style

Pryston, Dhara Beatriz de Amorim, Thatiane Veríssimo dos Santos Martins, Jailton Alves de Vasconcelos Júnior, Débora Olimpio da Silva Avelino, Mario Roberto Meneghetti, and Simoni Margareti Plentz Meneghetti. 2023. "Investigation of CeO2, MoO3, and Ce2(MoO4)3, Synthesized by the Pechini Method, as Catalysts for Fructose Conversion" Catalysts 13, no. 1: 4.

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