TPR Data Research Articles

HYDRODECHLORINATION OF DICLOFENAC IN AQUEOUS SOLUTION OVER PD/ZRO2 AND PD/ZRO2SIO2 CATALYSTS

Pd/ZrO2 and Pd/ZrO2SiO2 catalysts prepared by wet impregnation and reduced with H2 under mild (30 °C, aqueous suspension) or harsh (320 °C) conditions were compared in the hydrodechlorination of the microecotoxicant diclofenac in aqueous solution at 30 оС. According to TPR and XPS data, the addition of SiO2 to the support reduces the degree of metal-support interaction and facilitates the reduction of palladium. Despite the lower Pd0 fraction, the Pd/ZrO2 catalyst was more active in the batch reactor: after reduction at 320 °С, it slightly, and after mild reduction, signi cantly (7 times) exceeded Pd/ZrO2SiO2 in catalytic activity. XRD and TEM showed a wider size distribution of palladium nanoparticles in the Pd/ZrO2 sample, while low-temperature N2 adsorption, XPS, and TPR demonstrated better accessi-bility of palladium on the Pd/ZrO2 surface due to reduced decoration with support components and increased pore size. These features explain the increased activity of Pd/ZrO2. Testing in the ow system demonstrated higher DCF conversion in the presence of catalysts reduced at 320°C and higher stability of Pd/ZrO2SiO2 compared to Pd/ZrO2. The stability is ensured by the increased reducibility of Pd2+ with H2 and by the developed surface of Pd/ZrO2SiO2, which prevents deactivation under the action of HCl released in hydrodechlorination.

Efficient Catalysts of Ethanol Steam Reforming Based on Perovskite-Fluorite Nanocomposites with Supported Ni: Effect of the Synthesis Methods on the Activity and Stability

Catalysts based on perovskite—fluorite nanocomposites with supported nickel 5%Ni/[Pr0.15Sm0.15Ce0.35Zr0.35O2 + LaMn0.9Ru0.1O3] were synthesized by three different methods. Structural and surface features of as-prepared samples were elucidated by N2 adsorption, XRD, HR TEM with EDX; reducibility and reactivity were estimated by H2-TPR, and catalytic properties were studied in ethanol steam reforming in the 500–700 °C temperature range. The best catalytic activity without coke accumulation was demonstrated for the 5%Ni/[Pr0.15Sm0.15Ce0.35Zr0.35O2+ LaMn0.9Ru0.1O3] catalyst with nanocomposite support obtained by a simple sequential polymeric preparation method. Highly dispersed particles of metallic nickel strongly fixed on the support after the reaction were shown by the HR-TEM and H2 –TPR data. The catalyst provides stable full conversion of ethanol and hydrogen yield above 60% at 600 °C for at least 6 h.

Albemarle catalysts reports 1Q 2021 sales growth

The speciation of Ni in spent Fluid Catalytic Cracking catalysts is studied. Carefully performed XRD analyses with NiO/SiO2 samples used as calibration standards, demonstrate that the presence of NiO as a separate phase is reliably detected also for NiO concentration close to 0.1 wt% (1000 ppmw). Actually, both on real spent FCC catalysts (ECAT's) and on artificially contaminated industrial FCC catalysts, NiO is not detectable as a separate phase, even after contamination of the order of 15,000 ppmw of Ni. SEM–EDS experiments provide evidence of a largely preferential location of Ni on alumina particles present in the FCC catalyst mixture, thus acting as “nickel traps”. XRD, UV–vis and TPR data confirm that Ni deposits on alumina particles forming a hardly reducible surface and subsurface layer, giving rise to a solid whose composition is NixAl2O3+x with x << 0.25. As a result of this, the formation of extended Ni metal particles in the raiser reactor is avoided, being their unwanted dehydrogenation activity essentially eliminated. The absence of bulk NiO in the spent FCC catalysts (at least when Ni content is in the range 2000–10,000 ppmw) allows the classification of this material as a non-hazardous waste.

CO2 hydrogenation to liquid hydrocarbons via modified Fischer–Tropsch over alumina-supported cobalt catalysts: Effect of operating temperature, pressure and potassium loading

The effect of promoting 15%Co/Al2O3 catalyst with potassium on CO2 hydrogenation to longer-chain hydrocarbons was investigated. The catalysts used in this study were synthesized using an incipient wetness impregnation of the support with nitrate solutions. All catalysts were supported on γ-alumina and promoted with potassium (0 – 8%). The synthesized catalysts were characterized by XRD, BET, XPS, TPR and CO2-TPD analyses. The catalysts were evaluated for CO2 hydrogenation using a fixed-bed tube reactor. The CO2 conversion was found to increase with both the reaction temperature and pressure. The TPR data revealed that potassium limited the reduction of the catalyst, decreased the selectivity to methane and increased the selectivity to C2+ hydrocarbons. The maximum C2+ yield of 10.2%, with CO2 conversion of 42.3%, was obtained when 6 wt.% of potassium was added to the catalyst. It is believed that during the CO2 hydrogenation process over the catalysts that were promoted with potassium, CO2 is first converted to CO via reverse–water–gas–shift reaction, followed by subsequent hydrogenation of CO to hydrocarbons.

Termination of Parental Rights in New York: Why Such a Variation By County?

Termination of parental rights (“TPR”) ends the parent–child relationship though a process governed by state law. As a recent analysis of federal data revealed, TPR rates vary widely by state. In West Virginia, the TPR rate was 283 per 100,000. In New York State, the focus of this article, there were approximately 30 TPRs for every 100,000 children in 2014. Within New York State, TPR rates vary by county. In this exploratory piece, we analyze TPR rates in New York by county, noting discrepancies and seeking possible explanations for these variations, including possible effects of income disparities, single‐parent households, poor mental health, binge drinking, and drug addiction. This is an initial exploration only, and is not intended to be a rigorous quantitative study. Rather, our scope arises from what we have noticed from front line practice. It is our hope that researchers will use our exploratory findings for extended analysis, including analysis of TPR data from other states.

Fischer-Tropsch studies in a 3D-printed stainless steel microchannel microreactor coated with cobalt-based bimetallic-MCM-41 catalysts

Fischer-Tropsch (FT) synthesis was carried out using 3D-printed stainless steel (SS) microreactors, containing channels of dimensions 500 μm × 500 μm ×2.7 cm, to study the effect of Fe, Ru, and Ni on Co-MCM-41 catalyst. The mono and bimetallic cobalt-based catalysts: 15 % Co-MCM-41, 10 %Co5% Ru MCM-41, 10 %Co 5%Ni MCM-41, and 10 %Co 5%Fe MCM-41 were synthesized using one-pot hydrothermal method and characterized by SEM-EDX, TEM, TPR, FTIR, XPS, and low and wide angle XRD techniques. All the catalysts exhibited high surface area without the loss of ordered mesoporous structure as confirmed by large BET surface areas (400- 1000 m2/g) and low angle XRD data. The metal nanoparticles were in the range of 35−50 nm and well dispersed in a hexagonal matrix of MCM-41. TPR data indicate that all other metal oxides except that of cobalt can be reduced with H2 below 600 °C. Cobalt is present most likely as cobalt silicates that can only be reduced with H2 at a temperature over 650 °C. The microchannels of SS reactor were uniformly coated by dip coating a slurry of the catalyst with polyvinyl alcohol (PVA). The catalytic performance for FT synthesis was carried out in the SS microreactor at atmospheric pressure in the temperature range of 180–300 °C with H2/CO molar ratio of 3. Incorporation of the second metal in the Co-MCM-41 framework and the operating temperature had a significant effect on CO conversion and selectivity towards C1-C4 alkanes in FT synthesis. While the highest CO conversion of 74 % was obtained for CoFe-MCM-41 at 240 °C, the highest selectivity towards butane (11 %) and propane (39 %) was observed for CoRu-MCM-41 at 240 °C and CoFe-MCM-41 at 210 °C, respectively. The rate of deactivation of the catalysts -followed the order: CoRu-MCM-41> CoNi-MCM-41> Co-MCM-41> CoFe-MCM-41, indicating that CoFe-MCM-41 is the most suitable catalyst for F–T synthesis in terms of long term stability.

Synthesis of Dimethyl Ether from Synthesis Gas in the Presence of a Megamax 507/γ-Al2O3 Catalyst

The kinetics of the direct synthesis of dimethyl ether (DME) from synthesis gas (21.8 vol % CO, 5.2 vol % CO2, 5.3 vol % N2, and 67.7 vol % H2) is studied under laboratory flow reactors in a pressure range of 0.2–5 MPa in the presence of a bifunctional catalyst. The bifunctional catalyst is synthesized by pelletizing a mixture of appropriate fractions of the following milled commercial components: a Megamax 507 methanol catalyst and γ-alumina with a graphite additive. Data on the activation of the bifunctional catalyst are consistent with the TPR data for the original Megamax 507 sample, suggesting that the synthesis conditions for the bifunctional catalyst do not affect the state of copper oxide. At temperatures of up to 280°C, a space velocity of about 4000–10000 L/(kgcat h), and a pressure of 3–5 MPa, the productivity with respect to oxygenates (DME and methanol) grows linearly along with the load. An increase in load results in a limiting value that can be used to determine the maximum oxygenate productivity of the catalyst as a function of temperature and pressure. A set of experimental data on the effect of space velocity, temperature, and pressure on the composition of the converted gas and the DME/methanol ratio is derived.

Faradaic number as a criterion for the promotion effect of external electric field on the heterogeneous oxidative cracking of liquefied petroleum gas on ZSM-5 supported catalyst

The oxidative cracking of liquefied petroleum gas (LPG) in the presence of CO2 as oxidant, under a novel catalytic reaction system, with an electric field, was studied over a series of CrHZSM-5, HZSM-5 and NaZSM-5 catalysts. This research is the first report for olefin production with the synergetic effect of zeolite catalysts and external electric field. The prepared catalysts were characterized by XRD, SEM, FTIR, BET, NH3-TPD, H2-TPR and TGA techniques and an impedance analyzer with a potentiostat. Different parameters such as temperature, input electrical current, gap distance, amount of metal loading, oxidant, and GHSV were investigated. The activity was greatly increased by a weak electric field. The XRD pattern showed that the structure of the treated catalysts remained intact while BET results indicated the surface and micropore areas decreased after metal loading on HZSM-5. TPR data exhibited the reduction phenomenon of the catalysts. NH3-TPD analysis determined that Cr/HZSM-5 catalyst has more strong acid sites compared to NaZSM-5 and HZSM-5. According to TGA result, in the presence of an electric field, coke formation is decreased. Electrical conductivity played an important role in the reaction. Faradaic number was used to show the promotion effect of electric field. The results showed the electrons provided by external electric field, metal loading, and catalyst support were drastically promoted LPG to light olefins at 625 °C and 12 mA, which led to 42.58 and 92.12% ethylene yield and conversion, respectively, and 335.07 Faradaic number.

Peroxide oxidation of n-octane over Na-Fe-silicalite-1 and H-Fe-Silicalite-1 catalysts

The synthesis of the catalysts Na-Fe-silicalite-1(34), H-Fe-silicalite-1(34) and Na-Fe-silicalite-1(68) has been achieved by using the sol-gel method to incorporate the Fe as a T-atom in the zeolite framework (the values in brackets refer to Si/Fe molar ratios). Techniques that include FT-IR, XRD, SEM, TEM, ICP-OES, XRF, BET, TPR and TPD were used to characterize the catalysts. The XRD results show that only the ZSM-5 phase was present in all the synthesized catalysts. In addition, the TPR data showed a single peak assignable to Fe(III) species at 809.3, 806.5, and 777.9°C for Na-Fe-silicalite-1(34), H-Fe-silicalite-1(34) and Na-Fe-silicalite-1(68) respectively. The oxidation of octane over Na-Fe-silicalite-1(34) using H2O2 as an oxidant showed a direct dependence of conversion on temperature such that conversions of 9.6, 16.1 and 18% were recorded at 40, 60 and 80°C respectively. However, an inverse relationship was observed for the selectivity to terminal products (1-octanol and octanal). Selectivities of 30, 25 and 24% were recorded at 40, 60 and 80°C respectively. The H-Fe-silicalite-1(34) and Na-Fe-silicalite-1(68) catalysts were further tested at 80°C with the results showing that the H-Fe-silicalite-1(34) attained a terminal product selectivity of 26% at 19.8% conversion, while Na-Fe-silicalite-1(68) showed 27% selectivity to terminal products at 13.7% conversion. Only linear C8 products were observed under the conducted reaction conditions.

Catalytic oxidation of bis (2-chloroethyl) ether on vanadia titania nanocatalyst

Catalytic oxidation of bis (2-chloroethyl) ether (CEE) was carried over 6wt.% nanocatalyst (VTN) in the presence of ozone. The VTN was prepared by sol–gel method, while the impregnated catalyst (VTI) was prepared for the sake of comparative study. The catalysts were characterized by BET-SA, CEE-TPD, NH3-TPD, H2-TPR, XRD, SEM EDAX and TEM analyses. TPR and TPD data reveal that more acid and redox site was observed on nanocatalyst compared to that of conventional catalyst. The Brønsted acid sites were relatively more on nanocatalyst which were responsible for the higher ozone decomposition at low temperatures. The effects of O3/CEE ratio, reaction temperature, gas hourly space velocity (GHSV) and relative humidity (RH) were also investigated. The nanocatalyst exhibited the better performance, at low temperature (150°C) with high selectivity to carbon oxides. The transmission electron microscope data reveal that the sol–gel catalysts’ average particles size was 14. At 10% of RH, the complete conversion of CEE into carbon oxides was observed for nanocatalyst at 100°C with long-term stability. The ozone decomposition data reveal that the particle size and acidity had significant influence up to 100°C, whereas the thermal effects are predominant over the particle size above 150°C. A plausible reaction mechanism was proposed based upon the experimental data.

Synthesis of Dimethyl Ether from Synthesis Gas over the Megamax 507/γ-Al2O3 Catalyst

A laboratory flow setup loaded with a bifunctional catalyst was used for kinetic studies of the direct synthesis of dimethyl ether (DME) from synthesis gas (21.8 vol % CO, 5.2 vol % CO 2 , 5.3 vol % N 2 , rest H 2 ) at the pressure range of 0.2–5 MPa. The bifunctional catalyst was prepared by tabletting a mixture of milled fractions of industrial components: methanol catalyst Megamax 507 and γ-alumina with a graphite additive. The data on the activation of the bifunctional catalyst agree with the TPR data of the initial Megamas 507 that indicates no influence of the catalyst preparation conditions on the copper oxide state. The oxygenate (DME and methanol) production rate increases linearly with increasing load at temperature up to 280 °C and flow rate up to 4000–10000 L/(kgcat·h) at pressure of 3 to 5 MPa. An increase in load leads to reaching the limit value that allows the estimation of the maximal oxygenate production rate of the catalyst depending on temperature and pressure. A series of experimental data on the influence of flow rate, temperature, and pressure on the composition of the converted gas and on the DME/methanol ratio are reported.

Gold Catalysts on Y-Doped Ceria Supports for Complete Benzene Oxidation

Gold (3 wt. %) catalysts on Y-doped (1, 2.5, 5 and 7.5 wt. % Y2O3) ceria supports prepared by coprecipitation (CP) or impregnation (IM) were studied in complete benzene oxidation (CBO). A low-extent Y modification was chosen to avoid ordering of oxygen vacancies. The samples were characterized by XRD, TGA, XPS and TPR techniques. A positive role of air pretreatment at 350 °C as compared to 200 °C was established for all Y-containing catalysts and it was explained by cleaning the active sites from carbonates. The oxygen supply cannot be considered as a limiting step for benzene oxidation except for the high 7.5%-doped samples, as suggested by TGA and TPR data. On the basis of XPS results of fresh and used in CBO catalysts, the presence of cationic gold species does not seem important for high CBO activity. The gold catalyst on an IM support with 1% Y-doping exhibited the best performance. A 100% benzene conversion was achieved only over this catalyst and Au/ceria, while it was not reached even at 300 °C over all other studied catalysts. Gold and ceria particle agglomeration or coke formation should be excluded as a possible reason, and the most probable explanation could be associated with the importance of the benzene activation stage.

Effect of Alkali Carbonate/Bicarbonate on Citral Hydrogenation over Pd/Carbon Molecular Sieves Catalysts in Aqueous Media

The efficient citral hydrogenation was achieved in aqueous media using Pd/CMS and alkali additives like K2CO3. The alkali concentrations, reaction temperature and the Pd metal content were optimized to enhance the citral hydrogenation under aqueous media. In the absence of alkali, citral hydrogenation was low and addition of alkali promoted to ~92% hydrogenation without reduction in the selectivity to citronellal. The alkali addition appears to be altered the palladium sites. The pore size distribution reveals that the pore size of these catalysts is in the range of 0.96 to 0.7 nm. The palladium active sites are also quite uniform based on the TPR data. The catalytic parameters are correlated well with the activity data.

Hydrocracking of Polyolefin Thermal Cracking Waxes Over Ni-loaded Molecular Sieve Catalysts

The hydrocracking of thermal cracking waxes obtained from pyrolysis of polyolefin at 360°C for 120 min has been studied using Ni-loaded molecular sieves catalysts. According to XRD, TPR, and BET data, the presence of nickel oxide did not seem to damage the crystalline framework of the catalytic supports. Hydrocracking experiments were carried out in a stirred autoclave reactor at 300°C for 120 min under 2.0 MPa of hydrogen. The results suggested the existence of a balance between the acid and metal function over bifunctional catalysts, which affects hydrogenation and hydroisomerization of thermal cracking waxes. Hydrocracking reactions took place extensively over mixture of Ni/HBeta and ZSM-5, leading toward higher fractions of gases (30.2%) and diesel (23.5%). The higher fractions of gasoline (33.5%) and lube base oil (19.0%) were obtained over mixture of Ni/HSAPO-11 and ZSM-5. In contrast, hydrocracking reaction occurred in a lower extent over mixture of Ni/NMCM-41 and ZSM-5, which produces lube base oil with lower pour point (–10°C), gasoline and diesel with lower bromine numbers (1.1 and 0.8 g Br2/100 g sample). The viscosity index of lube base oil was in the range of 131–171 over all three mixed catalysts.

Effect of A-site substitution in perovskites: Catalytic properties of PrMnO3 and Ba/K/Ce substituted PrMnO3 for CO and PM oxidation

ABO3 type perovskite based catalysts with PrMnO3 composition and its A site substituted variants Pr0.8A0.2MnO3+δ/−δ (A=Ba or K or Ce) have been synthesized by sol–gel method. A systematic study has been carried out to understand the change in physicochemical properties, catalytic properties and related mechanistic aspects of the A site substituted ABO3 type perovskite materials with the help of XRD, BET-SA, SEM, XPS and H2-TPR techniques. These studies have inferred the altered oxidation states of B site cation Mn, as well as change in overall redox properties of PrMnO3, as a function of A site substitution. On the other hand, to study the impact on catalytic properties, these catalysts have been evaluated for two different reactions namely, CO and PM oxidation. The substitution/promotion of alkali metal (K) at A site of the PrMnO3 decreases its catalytic activity towards CO oxidation. However, Ba and Ce substitution in PrMnO3 enhanced the CO oxidation activity. The catalytic activity for PM oxidation was prominently enhanced with the substitution of K at the A site of PrMnO3 as well as with that of Ba and Ce substitutions. XRD, BET-SA, XPS and TPR data enabled to correlate the material properties with the catalytic activity, pointing out the role of substitution element with different valence state. The structure–property correlation for these two different reactions therefore, brings out certain findings about the role of substituted cation in PrMnO3 perovskite type catalysts.

Catalytic Decomposition of Natural Gas to CO/CO2-Free Hydrogen Production and Carbon Nanomaterials Using MgO-Supported Monometallic Iron Family Catalysts

Monometallic Fe, Co, and Ni/MgO catalysts with 50 wt.% metal loadings were prepared and examined for natural gas decomposition to nanocarbonaceous materials, particularly multiwalled carbon nanotubes (MWCNTs) and co-valuable hydrogen. The catalytic testing was carried out in a fixed-bed horizontal reactor at 700°C under atmospheric pressure. The fresh and/or used catalysts were characterized using XRD, TPR, HRTEM, SEM, TG/DTA, Raman spectroscopy, and BET surface measurements. The resulting data showed that the 50%Co/MgO catalyst displayed higher catalytic decomposition activity of natural gas to COx-free hydrogen production (∼88%), higher yield of MWCNTs, and excellent stability up to 10 h time-on-stream. On the other hand, the Ni-containing catalyst showed lower catalytic activity toward hydrogen and CNTs production, principally due to the formation of rock-salt MgxNi(1-x)O solid solution as observed from XRD and TPR data. Accordingly, the concentration of Ni particles required for natural gas feed was extremely low. The d orbital of Ni was presumed to be occupied during the formation of the solid solution, which inhibits the solublization or adsorption of hydrocarbons on Ni particles. The MWCNTs obtained over Ni-based catalyst had narrow and homogeneous diameters (∼11–13 nm). However, the Fe/MgO catalyst exhibited intermediate activity between those of Ni and Co˭MgO catalysts toward hydrogen production (∼44%). This catalyst produced mixtures of carbon nanofibers and nanotubes.

The state of nickel in spent Fluid Catalytic Cracking catalysts

The speciation of Ni in spent Fluid Catalytic Cracking catalysts is studied. Carefully performed XRD analyses with NiO/SiO2 samples used as calibration standards, demonstrate that the presence of NiO as a separate phase is reliably detected also for NiO concentration close to 0.1 wt% (1000ppmw). Actually, both on real spent FCC catalysts (ECAT's) and on artificially contaminated industrial FCC catalysts, NiO is not detectable as a separate phase, even after contamination of the order of 15,000ppmw of Ni. SEM–EDS experiments provide evidence of a largely preferential location of Ni on alumina particles present in the FCC catalyst mixture, thus acting as “nickel traps”. XRD, UV–vis and TPR data confirm that Ni deposits on alumina particles forming a hardly reducible surface and subsurface layer, giving rise to a solid whose composition is NixAl2O3+x with x<<0.25. As a result of this, the formation of extended Ni metal particles in the raiser reactor is avoided, being their unwanted dehydrogenation activity essentially eliminated. The absence of bulk NiO in the spent FCC catalysts (at least when Ni content is in the range 2000–10,000ppmw) allows the classification of this material as a non-hazardous waste.

Ordered mesoporous and bulk Co3O4 supported Pd catalysts for catalytic oxidation of o-xylene

Ordered mesoporous Co3O4 (3D) and the bulk counterpart Co3O4 (B) were prepared by a nanocasting route and precipitation method, respectively. Pd was next loaded on both of them by an impregnation method. All catalysts were tested for the total oxidation of o-xylene in the temperature range of 150–300°C. Mesoporous Co3O4 (3D) exhibited better activity than Co3O4 (B), and Pd addition further improved the catalytic activity of both the mesoporous and bulk Co3O4. The BET and TEM results indicated that the mesoporous catalysts had uniform channel dimensions and the mesostructure was little affected by Pd addition. The TPR and XPS data indicated that Pd was much more exposed on the surface of Co3O4 (3D) than that of Co3O4 (B). TPD results showed that Pd/Co3O4 (3DL) could activate the oxygen species more easily than Pd/Co3O4 (BL). Therefore, Pd/Co3O4 (3DL) presented the best activity among the four catalysts and achieved 90% conversion of 150ppm o-xylene at 249°C at a space velocity of 60,000mLg−1h−1.

Experimental evidences of the relationship between reducibility and micro- and nanostructure in commercial high surface area ceria

Two commercial high BET surface areas CeO2 are characterized, as received and after calcination at different temperatures, to better understand the relationship between reducibility and micro- and nanostructure. Combination of TPR data, Rietveld analysis of XRD diagrams and HREM/HAADF-STEM suggest that the nano-particles are responsible for Ce4+ reduction in the moderate temperature range. Results obtained in this work show that previous models based on kinetic and theoretical analysis can be fully supported by morphological characterization. This study unveils the key parameters that must be known in order to select appropriate commercial ceria samples.

Preparation and characterization of Pt-modified Co-based catalysts through the microemulsion technique: Preliminary results on the Fischer–Tropsch synthesis

The influence of the addition of small amounts of platinum (0.1–0.25% wt) to cobalt-based systems on Fischer–Tropsch synthesis was investigated. The solids were synthesized through microemulsion technique using TiO2 as the support. The best catalytic performance was achieved using Synperonic 13/6.5 as the surfactant. In all cases, the presence of platinum led to an increase in CO conversion which could be ascribed to the promotion of cobalt reducibility as evidenced by XPS. Moreover, the simultaneous reduction of cobalt and platinum precursors during synthetic procedure (ME1) was preferable to the consecutive one (ME2) probably as a result of a better Co–Pt interaction in the former case, as evidenced by TPR. TPR, Raman and XPS data also suggested that not only the presence of Co0 but also the appearance of Co–TiO2 interactions favor the catalytic performance and that in general those interactions are stronger for ME1 solids.