Density Of Basic Sites Research Articles

Influence of CeO2 supports prepared with different precipitants over Ru/CeO2 catalysts for ammonia synthesis

Three CeO2 supports with different concentration of surface oxygen vacancies were prepared by using C12H29NO (TPAOH), C2H8N2 (EDA) and NaOH as precipitant under hydrothermal conditions, respectively. Catalytic experiments showed that the Ru/CeO2-TPAOH catalyst has superior catalytic activity (22000 μmol g−1 h−1) than Ru/CeO2-EDA (19000 μmol g−1 h−1) and Ru/CeO2–NaOH (16500 μmol g−1 h−1) at 450 °C, 3 MPa. In addition, the introduction of Cs and Ba promoters improve the catalytic activity of the Ru/CeO2-TPAOH. However, the introduction of K promoter inhibits the catalytic activity of the Ru/CeO2-TPAOH. The 4% Cs promoter can effectively increase the catalytic activity of the Ru/CeO2-TPAOH (32000 μmol g−1 h−1). BET and TEM indicated that 5.5 nm average pore size of CeO2-TPAOH support contributes to the dispersion of active metal Ru. XPS and CO2-TPD proved that the Ru/CeO2-TPAOH catalyst has higher Ce3+ concentration, more oxygen vacancies, and higher basic site density, which are important factors for improving ammonia synthesis activity.

Support-dependent rate-determining step of CO2 hydrogenation to formic acid on metal oxide supported Pd catalysts

Investigating the mechanism of CO2 transformation into value-added chemicals is crucial for developing improved heterogeneous catalysts. In the present study, two common metal oxide (CeO2 and ZnO) supported Pd catalysts were studied in detail. Basic sites on the support promote CO2 activation to form surface adsorbed intermediates that further react with hydrogen atoms on metallic palladium to form formic acid. As such, both the support basicity and the (electronic) structure of Pd are critical parameters determining the catalytic performance, where the relative reaction rate for CO2 activation and hydrogenation decides which step is rate-determining. Pd/CeO2 with a higher density of basic sites readily activates CO2 and therefore the hydrogenation is the limiting step governed by the nature of the Pd species on the support. For Pd/ZnO, however, the rate-determining step is the formation of adsorbed carbonaceous intermediates due to the low density of basic sites and thus, the structure of Pd has little influence on the catalytic performance. These insights are further validated on a Pd/TiO2 catalyst, in which the optimized basic site density and Pd structure enhanced CO2 hydrogenation activity of up to an order of magnitude.

Zirconia phase effect in Pd/ZrO2 catalyzed CO2 hydrogenation into formate

In heterogeneous catalysis, transformation of CO2 into formate largely relies on supported palladium catalyst, in which the support and in particular the support basicity plays a critical role. In this study, we prepared a series of Pd catalysts loaded on ZrO2 bearing three different crystal phases, namely the tetragonal phase (ZrO2-T), the monoclinic phase (ZrO2-M), and the hybrid tetragonal and monoclinic phase (ZrO2-M&T). With the same metal loading, ZrO2-T supported Pd catalyst exhibited considerably higher intrinsic activity in CO2 hydrogenation into formate compared with the other two catalysts. Pd/ZrO2-T with 2 wt% Pd was the most active one in the series, affording a TOF of 2817 h−1 at 373 K. In situ DRIFTS spectroscopy, kinetic study and CO2-TPD analysis provided evidence that all Pd/ZrO2 catalysts follow a similar catalytic mechanism, and the origin of the superior activity for Pd/ZrO2-T is the higher density of weak basic sites on ZrO2-T, which facilitates the transformation of CO2 into the desirable surface adsorbed bicarbonate as the precursor for formate. This work highlights the importance of crystal-phase engineering of the support in tuning the catalytic activity of Pd based catalysts for CO2 hydrogenation.

Influence of synthesis route on physico-chemical and catalytic properties of nanosized K-LTL zeolites

Inorganic and organic routes were used to synthesize nanosized K-LTL zeolite. The role of synthesis route on the physico-chemical characteristics of synthesized materials was investigated using elemental analysis, powder x-ray diffraction, Raman spectral analysis, SEM, TEM, nitrogen-physisorption, MAS NMR and CO2-temperature programed desorption techniques. It was observed that K-LTL-org material composed of highly dispersed LTL nanocrystals, in contrast K-LTL-inorg sample showed highly agglomerated nanosized LTL particles because of high alkaline nature of Si, Al and K precursors used in the inorganic route. Additionally, material synthesized by organic route possessed large specific surface area with broad pore size (radius of 225 Å), and also high density of strong basic sites. Due to these properties, K-LTL-org sample showed superior performance in catalytic transesterification of glyceryl tributyrate compared to K-LTL -inorg sample. Also, the K-LTL-org catalyst showed excellent stability under applied reaction conditions and exhibited outstanding recyclability for (five cycles) without considerable loss of activity.

Highly Efficient Ru/MgO Catalyst with Surface‐Enriched Basic Sites for Production of Hydrogen from Ammonia Decomposition

AbstractDevelopment of highly active and stable catalyst for decomposition of ammonia to COx‐free hydrogen is an urgent and challenging task. Here, MgO (c‐MgO) supported Ru nanoparticles derived from Ru/4MgCO3 ⋅ Mg(OH)2 ⋅ 4H2O composite was prepared by deposition precipitation method and investigated as catalyst for NH3 decomposition. The use of 4MgCO3 ⋅ Mg(OH)2 ⋅ 4H2O as support precursor leads to high density of basic sites and highly dispersed Ru nanoparticles (3.8–6.0 nm) on the Ru/c‐MgO catalysts. Thus, the Ru/c‐MgO catalysts show much enhanced activities and robust stability in the long‐term run (over 100 hours). Characterization results reveal that the much enhanced dispersion of Ru nanoparticles, high density of surface base sites and strong interaction between Ru nanoparticles and c‐MgO all benefit the highly efficient Ru/c‐MgO catalysts in NH3 decomposition. Further improvements in activity can be achieved by modification of Ru/c‐MgO catalyst with an optimized KOH content. Therefore, it is believed that the use of 4MgCO3 ⋅ Mg(OH)2 ⋅ 4H2O as support precursor opens opportunity to achieve highly active and stable Ru/MgO catalysts through tuning the basic properties of catalysts.

Effect of cesium incorporation in hydrotalcite-like compounds

Hydrotalcite-like compounds are synthetic anionic clays that have outstanding adsorption and catalytic properties. Hydrotalcite nanoclays (Mg–Al layered hydroxides) were synthesized by co-precipitation method. Obtained solids were converted into mixed metal oxides by thermal decomposition at temperatures up to 723 K. High adsorption and reconstructive properties of the mixed metal oxides allowed incorporating metal ions in their structure. Thus, these materials can be used as ion traps from aqueous media. Cesium ions were incorporated into hydrotalcite lamellar structure by impregnation method. Effects of different loads of Cs+ and adsorption times on the material properties were studied. The materials were characterized by X-ray diffraction, surface area analysis, scanning electron microscopy, energy dispersive X-ray spectrometry for obtaining a localized chemical analysis, and temperature-programmed desorption of CO2 for measurement of basic sites density. The amounts of metal incorporated in the structure was high enough due to small size of Cs+ ion. Synthetized materials also demonstrated high concentrations of strong surface basic sites formed through a synergistic effect of Cs and Mg ions. Basic properties of Cs-containing hydrotalcites enable their potential use as catalysts of base-catalyzed reactions.

On the interaction of CO2 with Ni-Al catalysts

Knowledge of the CO2 interaction with the catalyst material is of great importance in the development of efficient catalysts for the methanation of CO2. In this study, the CO2 adsorption modes on and interaction with Ni-Al catalysts are systematically investigated by coupling FT-IR and CO2-TPD measurements next to pulsed and static CO2 chemisorption. The knowledge that is derived allows for a concise characterization of the CO2 interaction with Ni-Al catalyst by means of CO2-TPD. The strength of this technique in elucidating structure-activity relations of Ni-Al catalysts for CO2 methanation is demonstrated. For the study, catalysts with varying Ni loading are synthesized via co-precipitation and incipient wetness impregnation. CO2 adsorption under flow conditions close to room temperature leads to the formation of carbonate species on the catalyst. After elongated exposure of the catalyst to CO2, typically present under static conditions, Ni-CO species are also formed. The density of weak basic sites forming bicarbonate decreases with increasing Ni content for precipitated catalysts, while medium and strong basic sites forming bidentate, monodentate and bridged/”organic”-like species increase. Bicarbonate is the most abundant species on impregnated samples upon CO2 adsorption under flow conditions. Only a minor influence of the Ni loading on the catalyst basicity is observed for the impregnated samples. TPD results also indicate that CO2 adsorption on Ni-Al catalysts is an activated process. A more complete picture of the CO2 interaction with Ni-Al catalysts is obtained when starting TPD measurements at temperatures as low as 218 K. Bicarbonate, bidentate and monodentate carbonate exhibit desorption signals at 325, 416 and 500 K, respectively, while bridged/”organic”-like species show a broad desorption pattern between 550 and 750 K. An additional desorption signal is observed at 260 K. Pulsed CO2 chemisorption reveals that strong adsorption sites are filled first. The uptake of strongly chemisorbed CO2 determined from pulsed adsorption is significantly lower than corresponding values from static chemisorption.

Hydrothermal Reconstructing Routes of Alkali-Free ZnAl Layered Double Hydroxide: A Characterisation Study

A facile, rapid, and noninvasive method for reconstructing ZnAl layered double hydroxide (LDH) is reported. ZnAl LDH series were synthesized at different Zn2+/Al3+ atomic ratio (1.5-4) via an alkali-free method and reconstructed under hydrothermal route (HTM) for the first time. Fresh Zn/Al LDHs were activated at 300°C and reconstructed under hydrothermal process. A better insight and correlation study between the physiochemical properties of reconstructed ZnAl LDH in terms of their crystallinity, surface area and basicity also will be gained here. BET surface area of rehydrated samples increased up to 355 m2/g (Zn:Al ratio 3:1). CO2-TPD probed high number of basic sites density (0.1 mmol/g).

Environmentally Friendly, Co-catalyst-Free Chemical Fixation of CO2 at Mild Conditions Using Dual-Walled Nitrogen-Rich Three-Dimensional Porous Metal-Organic Frameworks.

Highly porous, polyhedral metal-organic frameworks (MOFs) of Co(II)/Ni(II), {[M6(TATAB)4(DABCO)3(H2O)3]·12DMF·9H2O} n (where M = Co(II) (1)/Ni(II) (2), H3TATAB = 4,4',4″- s-triazine-1,3,5-triyl-tri- p-aminobenzoic acid, and DABCO = 1,4-diazabicyclo[2.2.2]octane) have been synthesized solvothermally. Both MOFs 1 and 2 show a 2-fold interpenetrated 3D framework structure composed of dual-walled cages of dimension ∼ 30 Å functionalized with a high density of Lewis acidic Co(II)/Ni(II) metal sites and basic -NH- groups. Interestingly, MOF 1 shows selective adsorption of CO2 with high heat of adsorption ( Qst) value of 39.7 kJ/mol that is further supported by theoretical studies with computed binding energy (BE) of 41.17 kJ/mol. The presence of the high density of both Lewis acidic and basic sites make MOFs 1/2 ideal candidate materials to carry out co-catalyst-free cycloaddition of CO2 to epoxides. Consequently, MOFs 1/2 act as excellent recyclable catalysts for cycloaddition of CO2 to epoxides for high-yield synthesis of cyclic carbonates under co-catalyst-free mild conditions of 1 bar of CO2. Further, MOF 1 was recycled for five successive cycles without substantial loss in catalytic activity. Herein, rational design of rare examples of 3D polyhedral MOFs composed of Lewis acidic and basic sites exhibiting efficient co-catalyst-free conversion of CO2 has been demonstrated.

Propanol Amination over Supported Nickel Catalysts: Reaction Mechanism and Role of the Support

Ni-supported hydroxyapatite catalyst (Ni/HAP) was characterized and evaluated for propanol amination to propylamine at 423 K. The reaction proceeds via dehydroamination, a process that involves sequential dehydrogenation, condensation, and hydrogenation. Kinetic and isotopic studies indicate that α-H abstraction from propoxide species limits the rate of the dehydrogenation step and hence the overall rate of reaction. The rate of propanol dehydrogenation depends on the composition of the support and on the concentration of Ni sites located at the interface between Ni nanoparticles and the support. Ni/HAP is an order of magnitude more active than Ni/SiO2 and displays a higher selectivity toward the primary amine. The superior performance of Ni/HAP is attributed to the high density of basic sites on HAP, which are responsible for stabilizing alkoxide intermediates and suppressing the disproportionation and secondary amination of amines.

Morphology Effect of Ceria on the Ammonia Synthesis Activity of Ru/CeO2 Catalysts

Three Ru/CeO2 catalysts with different morphologies of CeO2 (cube spheres, microspheres and nano rods) were used to evaluate the support-morphology-dependent ammonia synthesis activity. Catalytic experiments show that the Ru/CeO2–CS catalyst has higher catalytic activity (27,000 µmol g−1 h−1) than Ru/CeO2–MS (21,000 µmol g−1 h−1) and Ru/CeO2–NR (15,000 µmol g−1 h−1) under the reaction conditions of 450 °C, 3 MPa, H2/N2 = 3:1 (60 mL min−1). The transmission electron microscopy analysis showed that the dispersion of active metal Ru is affected by the morphology of CeO2. Brunauer–Emmett–Teller indicates that the 3–5 nm the pore size of CeO2 supports contributes to the active metal Ru enters the pores of the CeO2 support, which improves the dispersion of Ru and prevents the sintering and agglomeration of Ru in some extent. TPR studies shown that the reduction of ruthenium oxide is influenced by the morphology of CeO2. XPS and CO2-TPD demonstrated that the Ru/CeO2–CS catalyst exhibited higher surface oxygen vacancies, higher basic site density and lower Ru binding energy, indicating that Ru nanoparticles in Ru/CeO2–CS is more electron-rich and are more capable of back-donating electrons to adsorbed N2 and subsequently activate N2. Our results indicate that the morphology effect of the CeO2 supports on the Ru/CeO2 catalyst is related to the pore size distribution and the surface oxygen vacancies of the CeO2 supports, ratio of Run+, basic site density. The CeO2–CS (cube spheres) morphology facilitated the dispersion of the active metal Ru and the 3 nm the pore size of CeO2–CS contributed to the Ru enters the pores of the support. And the Ru/CeO2–CS catalyst exhibited higher surface oxygen vacancies and lower Ru binding energy, which enhanced the adsorption of hydrogen and nitrogen species and thus weakened the N≡N bond.

Efficient Catalytic Production of Biodiesel with Acid-Base Bifunctional Rod-Like Ca-B Oxides by the Sol-Gel Approach

The search for acid-base bifunctional catalysts has become a hot topic in the preparation of biofuels from renewable resources. In the present work, a series of novel acid-base bifunctional metal-boron catalysts were successfully prepared by a sol-gel method and characterized by XRD, IR, SEM, TEM, TGA, BET, and TPD. Among those bifunctional solid materials, the Ca-B(700) catalyst had the highest density of both acid and base sites and showed excellent catalytic performance in the production of biodiesel from nonedible oils with high acid value. Under the optimal reaction conditions of 20/1 methanol/oil mole ratio and 4 wt % catalyst dosage at 105 °C for 2 h, a high biodiesel yield of 96.0% could be obtained from Jatropha curcas oil in one-pot. In addition, Ca-B(700) was also applicable to producing biodiesel from Firmiana platanifolia L.f. oil in a relatively low acid value, with an almost quantitative yield (98.5%) at 65 °C after 2 h. The Ca-B(700) catalyst had good stability and reusability, which is a promising acid-base bifunctional catalytic material for the preparation of biodiesel.

Effect of Acid‐Basic Sites Ratio on the Catalytic Activity to Obtain 5‐HMF from Glucose Using Al2O3‐TiO2‐W Catalysts

AbstractA series of Al2O3‐TiO2‐W materials with variation in W composition was prepared using an innocuous and easy sol‐gel method, under both acid and basic pH conditions. The morphology and composition of W in the materials were studied by Scanning Electron Microscopy (SEM) and Energy Dispersive X‐ray spectroscopy (EDS), respectively, Density of basic and acid sites by CO2 and NH3 temperature programmed desorption (TPD) technique, and physicochemical properties by N2 physisorption studies, X‐ray diffraction (XRD), and UV‐Vis spectroscopy. The catalytic properties of Al2O3‐TiO2‐W were examined for the conversion of glucose to produce 5‐hydroxymethylfurfural (5‐HMF) and the best yield of 5‐HMFobtained with the catalyst of 5 w% W load. This high yield level was achieved when the catalyst with 2.35 acid‐basic sites molar ratio was probed.

Synthesis and characterization of AMO LDH-derived mixed oxides with various Mg/Al ratios as acid–basic catalysts for esterification of benzoic acid with 2-ethylhexanol

Proven to possess distinguishable physical and acid-base properties superior to conventional LDHs, Aqueous Miscible Organic solvent-Layered Double Hydroxides (AMO-LDHs) were thus synthesized and used as precursors to prepare the Mg/Al mixed oxide catalysts in this work. The AMO-LDH based oxide catalysts with various ratios of Mg/Al were studied for the chemical and physical properties and the activity on esterification of benzoic acid with 2-ethylhexanol. The catalysts were characterized using BET, XRD, TGA, and XPS. Moreover, the acid-base properties were studied by using NH3-TPD, CO2-TPD, and X-ray Absorption Spectroscopy (XAS) techniques, both XANES and EXAFS. As a result, the Mg/Al mixed oxides after calcination at 500 °C still had the clay structure, and were found to possess both acid and base sites. As the Mg/Al ratio increased, the total density of acid and basic sites decreased. Moreover, the acid-basic strength depended on their phase compositions and coordination number. The activity of calcined LDHs catalysts was tested for the esterification of benzoic acid with 2-ethylhexanol, aimed at producing 2-ethylhexyl benzoate as the desired chemical. The products were analyzed using GC–MS/TOF. In summary, the conversion of benzoic acid was enhanced significantly using the MgAl mixed oxides as the catalysts, owing to the acid-base sites (both Mg2+O2− and Al3+O2− pairs) of the catalysts. The catalyst with the Mg/Al ratio of 4:1 can convert 66% benzoic acid to 2-ethylhexyl benzoate. Moreover, the other products were composed of 2-ethylhexanal, 3-heptanone, and 3-heptanol because of acid-base pairs.

Three inter-linked active sites in the dehydrogenation of n-octane over magnesium molybdate based catalysts and their influences on coking and cracking side reactions

Dehydrogenation of paraffins is an industrially practiced technique for the production of value added olefins. Molybdenum based catalysts are known for this application. This study focuses on the application of magnesium molybdate based catalysts with different Mg:Mo ratios for the dehydrogenation of n-octane. Several characterisation techniques were utilised to investigate the physicochemical properties of the bulk as well as the surfaces of the fresh and used catalysts. Three active sites with different functionalities were identified for these materials in the chosen catalytic reaction. Reduced molybdenum oxide (Mo4+ and Mo5+) sites were responsible for dehydrogenation, whereas MgO (involved in the MgMoO4 lattice or as the MgO phase) modified the density of basic sites that strongly controlled the adsorption of n-octane. Finally, acidic sites (likely from molybdenum oxides) promoted cracking and played an indirect role in increasing coke deposition over these materials. A mechanism that involves the simultaneous operation of these three active sites is proposed. The ratio between MgMoO4 and MoO3 was found to strongly influence the redox transition and thermal stability of these phases. The discussed science in this study can be used as a tool for preparation of advanced molybdenum based catalysts for different catalytic applications.

Design of Specific Acid-Base-Properties in CeO2-ZrO2-Mixed Oxides via Templating and Au Modification

Ceria-zirconia mixed oxides and gold supported oxides exhibit very good thermal stability and catalytic activity, as well as great selectivity. This work has been focused on the controlled synthesis and characterization of cationic- and amphiphilic-templated ceria, zirconia, and ceria-zirconia mixed oxides from nitrate and iso-propoxide precursors, and ceria-zirconia mixed oxides modified with gold via the deposition precipitation method with urea. The characterization of the acidic and basic properties was carried out through two test reactions. A complete chemical and structural characterization of the materials was done using Atomic Absorption Spectroscopy (AAS), Brunauer-Emmet-Teller Surface Analysis (N2-BET), X-Ray Diffraction (XRD), NH3- Temperature Programmed Desorption (TPD)/CO2-TPD, and Fourier Transform Infrared Spectroscopy (FTIR). Template techniques led to the formation of high surface area mesoporous materials with high activity and thermal stability. In general, the acid sites density was decreased, whereas the basic site density was increased by modification with Au or incorporation of zirconia in case of mixed oxides.

Pyroaurite‐based MgFe mixed oxides and their activity in aldol condensation of furfural with acetone: effect of oxide composition

AbstractBackgroundPyroaurite‐based MgFe oxides with varying Mg:Fe ratio were studied. The structural and acido‐basic properties were examined by number of experimental techniques. The oxide properties were correlated with the catalytic activity in aldol condensation of furfural with acetone.ResultsWell‐developed mesoporous structure was detected for all oxides. Peculiar continuous increase of concentration of basic sites and population of unsaturated strong basic O2− sites was observed with the rising amount of magnesium in the MgFe oxide matrix. A relatively higher concentration of Lewis acid Men+ sites was shown for low Mg:Fe ratios. Unambiguous correlation between conversion of furfural and the density of strong basic sites was proved by combined catalytic and statistical analysis. The contribution of other basic sites was found significantly less important. The impact of both acid and basic sites on the composition of reaction products was discussed.ConclusionsMgFe oxides revealed good catalytic performance in the aldol condensation of furfural with acetone where samples with a high Mg:Fe ratio were significantly more basic and had relatively enhanced furfural conversion (nominal Mg:Fe ratio 10; furfural conversion 88% and selectivity to F2Ac 34%; reaction conditions: batch reactor; 50 °C; acetone/furfural = 10 mol L–1). © 2018 Society of Chemical Industry

Selective Transfer Hydrogenation of Furfural into Furfuryl Alcohol on Zr-Containing Catalysts Using Lower Alcohols as Hydrogen Donors.

A series of zirconium-based catalysts were prepared for the selective transfer hydrogenation of biomass-derived furfural (FFR) into furfuryl alcohol with lower alcohols as hydrogen sources. The sample structures were clearly characterized using various methods, such as X-ray powder diffraction, thermogravimetric analysis, scanning electron microscope, NH3-temperature-programmed desorption (TPD), CO2-TPD, and nitrogen physisorption. Excellent furfuryl alcohol yield of 98.9 mol % was achieved over Zr(OH)4 using 2-propanol as a hydrogen donor at 447 K. The poisoning experiments indicated that basic centers displayed pronounced effect for FFR transfer hydrogenation. Moderate monoclinic phase content in ZrO2-x enhanced the conversion rate and furfuryl alcohol selectivity, whereas acid–basic site density ratio had slight influence on FFR conversion. Besides, Zr(OH)4 revealed good performance and stability after being repeated four times. The possible mechanism for this transfer hydrogenation process over Zr(OH)4 catalyst with 2-propanol as the hydrogen source was proposed.

CO2 methanation over Fe- and Mn-promoted co-precipitated Ni-Al catalysts: Synthesis, characterization and catalysis study

The methanation reaction of CO2 is in discussion to be a sustainable pathway to address future questions arising from limited primary energy feedstock and the accumulation of CO2 in the atmosphere. Therefore, the development of highly active and thermostable catalysts for this reaction is an indispensable matter of research. For this reason, an equimolar NiAlOx benchmark catalyst (44 wt.% Ni loading) was synthesized and modified by doping with Fe or Mn up to 10 wt.% of promoter by co-precipitation at constant pH 9. Their activity and stability performances in the CO2 methanation reaction were evaluated by comparing the conversion versus temperature characteristics before and after an aging period of 32 h at 500 °C. Material characterization studies comprising BET, XRD, in situ IR spectroscopy, XPS, H2 and CO2 chemisorption, and EPR/FMR contributed to derive structure-activity relationships and to obtain a deeper understanding of the catalytic behavior. Promotion with Mn led to a significant enhancement of the catalytic activity. This is assumed to be caused by a higher density of medium basic sites and an enhanced CO2 adsorption capacity on the activated catalyst related to interactions between Mn oxide species and the mixed oxide phase, in combination with a stabilization of the Ni surface area at moderate Mn loadings. Promotion with Fe increased the thermal stability of the catalyst, which is attributed to the formation of a Ni-Fe alloy during catalyst activation. For both phenomena, the optimum molar Ni to promoter ratio for co-precipitated catalysts was found to be around 5.

Sustainable Production of 2,3-Pentanedione: Catalytic Performance of Ba2P2O7 Doped with Cs for Vapor-Phase Condensation of Lactic Acid

Sustainable production of 2,3-pentanedione from lactic acid over Ba2P2O7 doped with Cs was investigated. Varying Cs components and calcination temperature can efficiently tune the acid–base properties of catalysts. It was found that both base site density and acid site density had a marked impact on catalytic performance for condensation of lactic acid to 2,3-pentanedione. Enhanced base site density and acid site density favor the catalytic activity. Furthermore, base/acid molar ratio has also played an important role on catalytic performance. From the observations based on the effect of Cs doped amount and calcination temperature, an appropriate base/acid molar ratio is around 8. Low reaction temperature as well as low LA LHSV favors selective formation of 2,3-pentanedione from lactic acid over the catalyst of 1.0CsNO3/2.5Ba2P2O7 calcined at 600 °C. Encouragingly, the condensation reaction of lactic acid proceeds efficiently at around 28 h on stream, and 2,3-pentanedione selectivity remains around 60%.