Ethanolic Transesterification with Methyl Acetate Catalyzed by SBA-15 Functionalized with Imidazolium–Sulfonic Groups Fernando Gazola, Iago Zapelini, José Assaf Crystals, 2026 The global demand for biodiesel production is steadily increasing. Conventional homogeneous basic catalysts, while widely used in the industry, face significant drawbacks, such as the requirement for high-quality feedstock, excessive waste generation, and multiple purification steps. In this study, an acidic silane (IM-CPTMS-BS-H2SO4) containing imidazolium and sulfonic groups was synthesized. Heterogeneous catalysts were then prepared by anchoring varying proportions of the silane onto SBA-15 mesoporous solids. These materials were characterized by FTIR, 13C and 29Si NMR, TGA, XRD, CHNS and acidity measurements. The catalysts were evaluated in the transesterification of methyl acetate with ethanol, with increasing catalytic conversions with the amount of grafted IM-CPTMS-BS-H2SO4. Furthermore, increasing the catalyst loading (from 2% to 5% wt.) and the reaction temperature (from 50 °C to 65 °C) led to higher methyl acetate conversion rates.
Exploring N2 capturing in Liquid Argon using Li-FAU Mol Sieve in the Iceberg Cryostat Pedro Bianchi Neto, Renato Soccol Junior, Flor de Maria Blaszczyk, Sergey Koshelev, Alan Hahn, et al. Journal of Instrumentation, 2025 Liquefied ultrapure noble gases are typically the chosen target for neutrino and dark matter experiments. Commonly, the required grade of purity of such cryogenic liquids in terms of O2 contamination is less than 100 ppt, which makes it necessary for the argon to circulate through adsorption columns filled, typically, with BASF Cu-0226S and Mol Sieve 4A for capturing O2 and H2O. Another requirement that emerged during the design of LBNF-DUNE is the purity of the Liquid Argon (LAr) in terms of N2 concentration, as it was observed that both N2 and O2 contaminations can cause the reduction of the LAr scintillation light emission. In particular, a decreasing behavior in the lifetime and the relative amplitude of the slow component is relevant from concentrations of 1 ppm of N2 and 0.1 ppm of O2. Recently, exploratory experiments performed in the Liquid Argon Purification Cryostat (PuLArC — ∼90 L of LAr) had been successfully used to purify LAr from N2 using an innovative solid adsorbent based on a Li-FAU Molecular Sieve. Here, we report experiments of N2 capturing in LAr carried out at the ICEBERG Cryostat (∼3000 L of LAr) at Fermilab. For the experiments, several controlled injections of N2 were made into the cryostat, and the impurity concentrations in the LAr (both for N2 and O2) were monitored using a calibrated gas analyzer during the purification process. The experimental data confirmed that the Li-FAU is capable of capturing the N2 from the LAr. A numerical methodology based on the mass and energy balances of the system was applied to better understand the behavior of the adsorption process and to help with the scale-up of the process. A Pore Diffusion Model (PDM) coupled with parameter optimization was proposed to predict the N2 concentration in the ICEBERG cryostat over time. The model parameters applied in this work were determined based on experimental data acquired in the PuLArC. The model was able to accurately reproduce the data from the ICEBERG, indicating that the mathematical model could be a valuable tool to design and operate the GAr/LAr system of LBNF-DUNE. It was possible to predict from simulations the necessary time to reach the required purity from an initial contamination concentration and also the number of purification cycles until solid saturation.
Comparing the performance of CuO dispersive media for O2 capturing in Liquid Argon A.M. Caffer, R.G. Gonçalves, H.B. Pizzi, D.S. Passos, M.H. Carvalho, et al. Journal of Instrumentation, 2025 In this work, we have explored the potential of oxygen capture in Liquid Argon (LAr) of the innovative CuO dispersive layered double hydroxide media (R-LDH) and the Ce-doped R-LDH. Low-temperature experiments in the LAr Purification Cryostat (PuLArC) at IFGW/Unicamp were performed using LAr circulation through two filters, one containing the R-LDH (or the Ce-doped R-LDH) material and the other the BASF commercial copper material (Cu-02265 — proposed as a reference O2 getter media by Fermilab) for comparison. Interestingly, the experiments performed in PuLArC revealed that the R-LDH and Ce-doped R-LDH innovative media were capable of capturing O2 from recirculating LAr in PuLArC. For instance, the R-LDH media reduced the O2 contaminants concentration by 80% of its initial values after 200 min of LAr circulation. As for the reference media BASF Cu-S0226, this media reduced the O2 concentration by 40% of its initial value in the same time window. The performance/kg of the studied media will be compared and we will discuss the putative higher potential of the innovative Ce-doped and pure R-LDH media for O2 capturing in LAr which may invoke further tests of these media in larger scale LAr cryostats, possibly at Fermilab and CERN.
Influence of La2O3 Addition on CuO/CeO2 Catalysts for the Water-Gas Shift Reaction Tatiana de Freitas Silva, José Mansur Assaf, Alessandra Fonseca Lucrédio, Cristhiane Guimarães Maciel Reis, Karina Arruda Almeida Langmuir, 2025 CuO/CeO2 and CuO/xCeO2-yLa2O3 catalysts, synthesized with varying CeO2 and La2O3 molar ratios (1:1, 1:2, and 2:1), were prepared via the hydrothermal method and tested in the water-gas shift reaction (150-350 °C). La2O3 addition altered structural properties, reducing surface area and copper dispersion. XANES and in situ XRD confirmed metallic Cu species during reduction and reaction. Catalytic tests revealed CuO/CeO2 excelled at low temperatures, while La2O3-doped catalysts, especially CuO/1CeO2-1 La2O3, performed better at 250-350 °C. Stability tests showed La2O3-doped catalysts resisted deactivation and sintering better than CuO/CeO2, even with CO2 and H2 in the feed.
Improving Coking Resistance and Catalytic Performance of Ni Catalyst from LaNiO3 Perovskite by Dispersion on SBA-15 Mesoporous Silica for Hydrogen Production by Steam Reforming of Ethanol Isa Carolina Silva Costa, Elisabete Moreira Assaf, José Mansur Assaf Topics in Catalysis, 2024 A strategic option for the production of H2 from renewable resources is use of the ethanol steam reforming reaction. Catalysts based on nickel have been widely investigated for this reaction, offering the advantages of low cost and high activity. However, a difficulty is that nickel may be strongly deactivated by coke formation. Perovskite-type mixed oxides are promising precursors for nickel-based catalysts, since their reduction leads to the formation of highly dispersed metal particles that can mitigate carbon deposition. However, high calcination temperatures are required for perovskite structure formation, resulting in low surface areas and limiting the effectiveness of this method. In order to address this difficulty, the present work proposes a novel strategy whereby the perovskite-type oxide LaNiO3 is supported on SBA-15. Characterization of the catalysts was performed using XRF, XRD, SEM, TPR, TEM, BET, H2-TPD, and TGA techniques. Their performances were then evaluated in catalysis of the ethanol steam reforming reaction to produce hydrogen. Calcination at 750 °C resulted in formation of highly dispersed perovskite on a support that presented high specific surface area. The catalyst obtained from reduced LaNiO3/SBA-15 with 33 wt% perovskite was the most active in the reaction. Analyses using TGA and SEM showed the formation of carbon mainly over Ni catalysts obtained from bulk LaNiO3 perovskite, while supporting LaNiO3 on SBA-15 led to lower deposition of carbon. The superior performance of this material in catalysis could be attributed to the dispersion of the perovskite on SBA-15, resulting in smaller size of the Ni metal particles formed during the reduction, compared to the catalyst derived from bulk perovskite. This promising method could be used in the production of a wide range of other catalysts.
Introduction to high-value chemicals and energy production from CO2 Gabriel L. Catuzo, Ananda V.P. Lino, Elisabete M. Assaf, José M. Assaf, Rita M.B. Alves Advances and Technology Development in Greenhouse Gases Emission Capture and Conversion Carbon Dioxide Conversion to Chemicals and Energy, 2024
Effect of Synthesis Methods for ZnZrOx Oxides Associated with SAPO-34 on the Production of Light Olefins By CO2 Hydrogenation AVP Lino, EM Assaf, JM Assaf Catalysis Letters 156 (5), 143 , 2026 2026
Ethanolic Transesterification with Methyl Acetate Catalyzed by SBA-15 Functionalized with Imidazolium–Sulfonic Groups F Gazola, I Zapelini, J Assaf Crystals 16 (4), 258 , 2026 2026
Uso de surfactantes orgânicos na síntese de catalisadores de CuO-ZnO para hidrogenação de CO2 a metanol RA Angeli, GM de Paula, JM Assaf, JF Gomes 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Catalisadores Funcionais para a Produção de Hidrocarbonetos via Fischer–Tropsch: Ênfase nas Rotas de Síntese LNR de Paula, GM de Paula, LA Branco, JM Assaf, JF Gomes 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Efeito da carga de Cu e Fe na hidrogenação do CO2 para etanol sobre catalisadores CuFe/ZIF-8 ME Ribeiro, GL Catuzo, JM Assaf, EM Assaf 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Aplicação de catalisadores zeolíticos multifuncionais para conversão direta do furfural em γ-valerolactona Y Lima, L Vieira, J Assaf, E Assaf 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Hidrogenação catalítica do CO2 à metanol sob óxidos de terras raras combinados com ZnO WD de Macêdo Souza, JM Assaf 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Eficiência de Catalisadores ZnO-CeO2/H+-ZSM-5 na Conversão Catalítica de CH4 e CO2 em Ácido Acético G de Freitas Lopes, AF Lucrédio, LH Vieira, JF Gomes, JM Assaf, ... 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Influência do precursor do catalisador CuO-ZnO na hidrogenação de CO2 a metanol GM de Paula, RA Angeli, LNR de Paula, JM Assaf, JF Gomes 23º CBCAT–Congresso Brasileiro de Catalise 1 (1) , 2025 2025
Oxidative Coupling of Methane GL Catuzo, LF Rasteiro, LB Lopes, LH Vieira, JM Assaf, EM Assaf 2025
Enhanced oxygen mobility in NiAg alloy catalysts for methane dry reforming: The role of AgO nanoparticles ARG Caranton, AVP Lino, C Macchiutti, NRC Huaman, E Annese, ... Catalysis Today 455, 115316 , 2025 2025 Citations: 3
CuO-ZnO Oxides Derived from Lamellar Structures As Catalysts for the Hydrogenation of CO 2 to Methanol RA Angeli, JF Gomes, L Paula, J Assaf, JF Gomes The 29th North American Catalysis Society Meeting , 2025 2025
Hollow Iron-Based LDH Structures Applied to Low-Temperature Rwgs Reaction RGL Gonçalves, PR Kasala, J Assaf, J Rodriguez, E Assaf The 29th North American Catalysis Society Meeting , 2025 2025
Impact of the Metal Center (Zr or Hf) of the Cu/Uio-67 on the Catalytic Performance for Alcohols Production Via CO 2 Hydrogenation LNR de Paula, JF Gomes, JM Assaf The 29th North American Catalysis Society Meeting , 2025 2025
Exploring N 2 capturing in Liquid Argon using Li-FAU Mol Sieve in the Iceberg Cryostat P Bianchi Neto, R Soccol Junior, FM Blaszczyk, S Koshelev, A Hahn, ... Journal of Instrumentation 20 (06), C06045 , 2025 2025 Citations: 1
Ensuring High-Purity Liquid Argon for the LBNF FDC: Collaborative Cryogenics Research Between UNICAMP and Fermilab R Doubnik, M Adamowski, C Adriano, TPM Alegre, EM Assaf, JM Assaf, ... No journal information , 2025 2025 Citations: 1
Evaluation of the potassium incorporation method in MgFe catalysts derived from layered double hydroxides in the hydrogenation of CO2 RGL Goncalves, GL Catuzo, JM Assaf, EM Assaf Catalysis Today 448, 115166 , 2025 2025 Citations: 1
Comparing the performance of CuO dispersive media for O 2 capturing in Liquid Argon AM Caffer, RGL Gonçalves, HB Pizzi, DS Passos, MH Carvalho, C Reis, ... Journal of Instrumentation 20 (03), C03043 , 2025 2025
Impact of the K and Fe insertion methods in KFeCeZr catalysts on the CO2 hydrogenation to C2/C3 olefins at room pressure AVP Lino, LH Vieira, EM Assaf, JM Assaf Chemical Engineering Science 302, 120898 , 2025 2025 Citations: 6
Influence of La 2 O 3 Addition on CuO/CeO 2 Catalysts for the Water–Gas Shift Reaction T de Freitas Silva, JM Assaf, AF Lucrédio, CGM Reis, KA Almeida Langmuir 41 (5), 3108-3120 , 2025 2025 Citations: 14
MOST CITED SCHOLAR PUBLICATIONS
High efficiency steam reforming of ethanol by cobalt-based catalysts MS Batista, RKS Santos, EM Assaf, JM Assaf, EA Ticianelli Journal of Power Sources 134 (1), 27-32 , 2004 2004 Citations: 337
Characterization of the activity and stability of supported cobalt catalysts for the steam reforming of ethanol MS Batista, RKS Santos, EM Assaf, JM Assaf, EA Ticianelli Journal of Power Sources 124 (1), 99-103 , 2003 2003 Citations: 302
Structural features of La1− xCexNiO3 mixed oxides and performance for the dry reforming of methane SM Lima, JM Assaf, MA Pena, JLG Fierro Applied Catalysis A: General 311, 94-104 , 2006 2006 Citations: 272
Evaluation of the performance of Ni/La2O3 catalyst prepared from LaNiO3 perovskite-type oxides for the production of hydrogen through steam reforming and oxidative steam … SM de Lima, AM da Silva, LOO da Costa, JM Assaf, G Jacobs, BH Davis, ... Applied Catalysis A: General 377 (1-2), 181-190 , 2010 2010 Citations: 219
Influence of calcium content in Ni/CaO/γ-Al2O3 catalysts for CO2-reforming of methane JAC Dias, JM Assaf Catalysis today 85 (1), 59-68 , 2003 2003 Citations: 206
Catalytic evaluation of perovskite-type oxide LaNi1− x RuxO3 in methane dry reforming GC Araujo, SM Lima, JM Assaf, MA Peña, JLG Fierro, ... Catalysis Today 133, 129-135 , 2008 2008 Citations: 163
Autothermal reforming of methane over Ni/γ-Al 2O3 catalysts: the enhancement effect of small quantities of noble metals JAC Dias, JM Assaf Journal of power sources 130 (1), 106-110 , 2004 2004 Citations: 163
Dry reforming of methane on Ni–Mg–Al nano-spheroid oxide catalysts prepared by the sol–gel method from hydrotalcite-like precursors AR González, YJO Asencios, EM Assaf, JM Assaf Applied Surface Science 280, 876-887 , 2013 2013 Citations: 156
Hydrogen production by steam reforming of ethanol over Ni-based catalysts promoted with noble metals LPR Profeti, JAC Dias, JM Assaf, EM Assaf Journal of Power Sources 190 (2), 525-533 , 2009 2009 Citations: 131
Hydrogen production through oxidative steam reforming of ethanol over Ni-based catalysts derived from La 1-x Ce x NiO 3 perovskite-type oxides SM de Lima, AM da Silva, LOO da Costa, JM Assaf, LV Mattos, R Sarkari, ... Applied Catalysis B: Environmental , 2012 2012 Citations: 129
Methane conversion reactions on Ni catalysts promoted with Rh: Influence of support AF Lucrédio, JM Assaf, EM Assaf Applied Catalysis A: General 400 (1-2), 156-165 , 2011 2011 Citations: 125
Influence of the supramolecular structure and physicochemical properties of cellulose on its dissolution in a lithium chloride/N, N-dimethylacetamide solvent system LA Ramos, JM Assaf, OA El Seoud, E Frollini Biomacromolecules 6 (5), 2638-2647 , 2005 2005 Citations: 124
Ni–Fe catalysts based on perovskite-type oxides for dry reforming of methane to syngas SM de Lima, JM Assaf Catalysis Letters 108 (1), 63-70 , 2006 2006 Citations: 121
Electrocatalytic CO2 reduction to C2+ products on Cu and CuxZny electrodes: effects of chemical composition and surface morphology AHM da Silva, SJ Raaijman, CS Santana, JM Assaf, JF Gomes, ... Journal of Electroanalytical Chemistry 880, 114750 , 2021 2021 Citations: 95
Reforming of a model biogas on Ni and Rh–Ni catalysts: Effect of adding La AF Lucrédio, JM Assaf, EM Assaf Fuel Processing Technology 102, 124-131 , 2012 2012 Citations: 94
Insights into the methanol synthesis mechanism via CO2 hydrogenation over Cu-ZnO-ZrO2 catalysts: Effects of surfactant/Cu-Zn-Zr molar ratio FCF Marcos, L Lin, LE Betancourt, SD Senanayake, JA Rodriguez, ... Journal of CO2 Utilization 41, 101215 , 2020 2020 Citations: 91
Effect of nature of ceria support in CuO/CeO2 catalyst for PROX-CO reaction CG Maciel, TF Silva, MI Hirooka, MN Belgacem, JM Assaf Fuel , 2012 2012 Citations: 86
Noble Metals in Recent Developments of Heterogeneous Catalysts for CO 2 Conversion Processes LH Vieira, LF Rasteiro, CS Santana, GL Catuzo, AHM da Silva, JM Assaf, ... ChemCatChem 15 (14), e202300493 , 2023 2023 Citations: 83
La 1− x Ca x NiO 3 Perovskite Oxides: Characterization and Catalytic Reactivity in Dry Reforming of Methane SM De Lima, MA Pena, JLG Fierro, JM Assaf Catalysis letters 124 (3), 195-203 , 2008 2008 Citations: 80
Insights into the alloy-support synergistic effects for the CO2 hydrogenation towards methanol on oxide-supported Ni5Ga3 catalysts: An experimental and DFT study LF Rasteiro, RA De Sousa, LH Vieira, VK Ocampo-Restrepo, LG Verga, ... Applied Catalysis B: Environmental 302, 120842 , 2022 2022 Citations: 74