Nanostructured Fe2O3 dispersed on SiO2 as catalyst for high temperature sulfuric acid decomposition—Structural and morphological modifications on catalytic use and relevance of Fe2O3-SiO2 interactions

Nadar, Ashish; Banerjee, Atindra Mohan; Pai, Mrinal R.; Meena, Sher Singh; Pai, Rajesh V.; Tewari, R.; Yusuf, S. M.; Tripathi, A. K.; Bharadwaj, S.R.

doi:10.1016/j.apcatb.2017.05.045

Cited by 72 publications

(25 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Sulfur‐iodine cycle was established at a pilot plant scale by Japan Atomic Energy Research Institute and demonstrated H 2 production rate of 32 L/h for 20 hours in 2004 . In the recent past, India and China have also demonstrated the S‐I cycle in closed glass loop. However, S‐I cycle suffers a major drawback of requirement of very high temperature ( T > 800°C), restricting the options for material of construction.…”

Section: Introductionmentioning

confidence: 99%

Investigations on the hydrolysis step of copper‐chlorine thermochemical cycle for hydrogen production

et al. 2019

View full text Add to dashboard Cite

Summary Detailed investigations of CuCl2 hydrolysis step of Cu–Cl thermochemical cycle were carried out on various aspects: (a) characterization and thermal properties of reactants/products using X‐ray diffraction (XRD), thermogravimetry–mass spectrometry (TG‐MS), scanning electron microscopy (SEM), temperature‐programmed desorption (TPD), and extended X‐ray absorption fine structure (EXAFS); (b) performance evaluation of fixed bed hydrolysis; (c) parametric optimization with respect to S/Cu, flow rate (gas hourly space velocity, GHSV), reaction duration, temperature, and particle size; and (d) monitored hydrolysis using isothermal TG experiments at 360°C, 370°C, 380°C, 390°C, and 400°C to derive kinetic parameters rate constant (k) and activation energy (Ea) on the basis of the shrinking‐core model. 97% conversion to Cu2OCl2 at 17 630 h−1 of GHSV, 400°C was achieved using ball‐milled CuCl2 (BM6), as compared with that of 55% over commercial un–ball‐milled reactant, CuCl2 (UBM). Correspondingly, higher k value of 2.84 h−1 over BM6 as compared with 0.97 h−1 over UBM reactant at 400°C was achieved. Ea for hydrolysis of BM6 was 93 kJ/mol, while it was 106 kJ/mol for UBM as derived from the Arrhenius plot. A probable pathway for CuCl2 hydrolysis is proposed here. It was found to be diffusion controlled, and the particle size of reactant molecules affects the packing and diffusion length. Based on our investigations, it is very unlikely to get >99% phase pure product (Cu2OCl2). Cu2OCl2 is labile in nature and tends to transform into structurally similar and stable compounds CuO and CuCl2.

show abstract

Section: Introductionmentioning

confidence: 99%

Investigations on the hydrolysis step of copper‐chlorine thermochemical cycle for hydrogen production

et al. 2019

View full text Add to dashboard Cite

show abstract

“…As displayed in Table S5, 2Ni/Sn−MCM‐41 sample contains a higher surface Ni 0 /Ni 2+ ratio, which indicates the promoter Sn improved the metallic Ni on the sample surface and responsible for the enhanced performance. The O 1s peak could be deconvoluted into three peaks: the major one located at ∼533 eV is assigned to the O 2− existence in the SiO 2 matrix (O α ), the peak at the higher BE values of ∼535 eV corresponding to the surface adsorbed water or chemisorbed surface oxygen (O γ ), while another minimal peak appeared at ∼530 eV ascribed to the lattice oxygen (O β ) present in SnO x and/or NiO x species [28] . Thus, the interfacial effect of Ni and SnO x might trigger the charge transfer and further influences the interaction between metallic Ni and support.…”

Section: Resultsmentioning

confidence: 99%

Promotional Effect of Ni−Sn Interaction over Ni Supported on Sn‐incorporated MCM‐41 Catalysts for CO₂ Reforming of CH₄

et al. 2021

View full text Add to dashboard Cite

Sintering of active Ni sites and deposition of coke remain challenging issues for catalytic dry reforming of methane. Herein, Ni supported on the Sn‐incorporated MCM‐41 catalysts were synthesized and tested for DRM process. The structural and physicochemical properties of fresh and spent samples were studied by N2 adsorption‐desorption, XRD, H2‐TPR, XPS, TEM, STEM‐EDS, Raman, and TGA techniques. It was revealed that Sn addition improved the dispersion and decreased the size of active Ni nanoparticles by tuning the charger transfer between Ni and Sn. The formation of Ni−SnOx interface provides more possibilities to activate CO2. The best results were obtained by 2Ni/Sn−MCM‐41 sample with the Ni/Sn mole ratio of 2 : 1, contributing CH4 conversion of 95% and CO2 conversion of 94% at 800 °C. Moreover, the presence of Sn increased the resistance to sintering of Ni‐based catalysts during the severe conditions, thereby the Ni nanoparticle size only appeared a slight growth after 32 h TOS. Combined with the characterization of the spent 2Ni/Sn−MCM‐41 sample, it was revealed that the coke deposition of the deactivated catalyst was dominated by amorphous carbon, which could be responsible for the desirable regeneration ability of the catalyst.

show abstract

“…9). During polishing, these agglomerates, which formed with increase in weight percent of SiO2, can be detached from the surface of composite [21].…”

Section: Distribution Of Sio2 In Al Matrixmentioning

confidence: 99%

The Effect of SiO2 Content and Shape on Mechanical Properties of Al Matrix Composites

Khademi

Khodeir

Mahdizadeh

et al. 2021

Preprint

View full text Add to dashboard Cite

Physical properties and processing parameters of the reinforcing phase such as shape and content can dramatically influence the mechanical properties of the composites. In this project, the effect of different shapes of silicon dioxide or silica (SiO2) reinforcement including nanoparticle and nanotube as well as their weight percent (1, 3, 5 and 10 wt %) on the mechanical properties of aluminum (Al) composite were investigated. The silica nanotubes (SNTs) were prepared by hydrothermal methods. In order to achieve a good dispersion, Al powders were coated by cetyl trimethyl ammonium bromide (CTAB) to obtain a surface positive charge. Then, SiO2–Al powders were obtained by electrostatic self-assembly to realize the homogeneous adsorption of SiO2 nano reinforcement on Al powders. Finally, SiO2-reinforced Al matrix composites were fabricated by powder metallurgy. Characterization of composites was carried out by transmission electron microscopy (TEM), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). For determination of the mechanical properties of the composite, the compressive strength and density were investigated.Results showed a significant reduction in the relative density from 98% to 84% for composites containing 0 to 10 wt % of SiO2. The compressive strength exhibited a moderate increase by adding SNTs while in samples containing SiO2 nanoparticles, the mechanical properties improved and reached a peak value of 225 MPa at 5 wt % SiO2 nanoparticles (~40% increase compared to pure Al). However, a further increase in nanotubes content resulted in a considerable reduction in compressive strength. This can be attributed to the increase in porosity and agglomeration of nano reinforcement in the composite.

show abstract

Nanostructured Fe2O3 dispersed on SiO2 as catalyst for high temperature sulfuric acid decomposition—Structural and morphological modifications on catalytic use and relevance of Fe2O3-SiO2 interactions

Cited by 72 publications

References 53 publications

Investigations on the hydrolysis step of copper‐chlorine thermochemical cycle for hydrogen production

Investigations on the hydrolysis step of copper‐chlorine thermochemical cycle for hydrogen production

Promotional Effect of Ni−Sn Interaction over Ni Supported on Sn‐incorporated MCM‐41 Catalysts for CO₂ Reforming of CH₄

The Effect of SiO2 Content and Shape on Mechanical Properties of Al Matrix Composites

Contact Info

Product

Resources

About

Nanostructured Fe2O3 dispersed on SiO2 as catalyst for high temperature sulfuric acid decomposition—Structural and morphological modifications on catalytic use and relevance of Fe2O3-SiO2 interactions

Cited by 72 publications

References 53 publications

Investigations on the hydrolysis step of copper‐chlorine thermochemical cycle for hydrogen production

Investigations on the hydrolysis step of copper‐chlorine thermochemical cycle for hydrogen production

Promotional Effect of Ni−Sn Interaction over Ni Supported on Sn‐incorporated MCM‐41 Catalysts for CO2 Reforming of CH4

The Effect of SiO2 Content and Shape on Mechanical Properties of Al Matrix Composites

Contact Info

Product

Resources

About

Promotional Effect of Ni−Sn Interaction over Ni Supported on Sn‐incorporated MCM‐41 Catalysts for CO₂ Reforming of CH₄