Experimental study of solar reactors for carboreduction of zinc oxide

Adinberg, R.; Epstein, Michael

doi:10.1016/s0360-5442(03)00182-8

Cited by 31 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The increase in the intensities of the peaks representing weight loss at temperatures higher than 800 8C is likely due to the reduction of ZnO by carbon. [49] Even though the DTG curves for the composites exhibit similar peaks to those of MOF-5, a small peak around 200 8C is a new feature. It can either correspond to strongly bound water [39] or it can be due to the decomposition of epoxy groups from the GO component.…”

Section: Resultsmentioning

confidence: 86%

Enhanced Adsorption of Ammonia on Metal‐Organic Framework/Graphite Oxide Composites: Analysis of Surface Interactions

Petit

Bandosz

2009

Adv Funct Materials

321

227

View full text Add to dashboard Cite

Composites of the metal‐organic framework (MOF), MOF‐5, and graphite oxide (GO) with different ratios of the two components are prepared and tested in ammonia removal under dry conditions. The parent and composite materials are characterized before and after exposure to ammonia by sorption of N2, X‐ray diffraction, thermal analyses, and FT‐IR spectroscopy. The results show a synergetic effect resulting in an increase in the ammonia uptake compared to the parent materials. It is linked to enhanced dispersive forces in the pore space of the composites. Additionally, ammonia interacts with zinc oxide tetrahedra via hydrogen bonding and is intercalated between the layers of GO. Retention of a large quantity of ammonia eventually leads to a collapse of the MOF‐5 structure in the composites. The effect resembles that observed when MOF‐5 is exposed to water. Taking into account the similarity of ammonia and water molecules, it is hypothesized that ammonia causes a destruction of the MOF‐5 and composite structure as a result of its hydrogen bonding with the zinc oxide clusters.

show abstract

Section: Resultsmentioning

confidence: 86%

Enhanced Adsorption of Ammonia on Metal‐Organic Framework/Graphite Oxide Composites: Analysis of Surface Interactions

Petit

Bandosz

2009

Adv Funct Materials

321

227

View full text Add to dashboard Cite

show abstract

“…Thus, the development of efficient and stable redox materials remains one of the major bottle necks for the effective commercialization of this technology. Alternatively, the maximum temperature of the redox cycles can be decreased by using a carbonaceous reducing agent (such as carbon or methane). − Several aspects are to be considered for selecting appropriate redox materials such as solid phase stability during the operating conditions, resistance to carbon deposition, formation of metal carbide during the reduction step with CH 4 in the case of a carbothermal process, etc.…”

Section: Introductionmentioning

confidence: 99%

Tailoring Hybrid Nonstoichiometric Ceria Redox Cycle for Combined Solar Methane Reforming and Thermochemical Conversion of H₂O/CO₂

Nair

Abanades

2016

Energy Fuels

View full text Add to dashboard Cite

Combining partial oxidation of methane with H2O/CO2 splitting under solar thermal conditions presents a very promising strategy for producing solar fuels. In order to achieve this, the development of stable and efficient redox catalysts is necessary, among which ceria (CeO2) seems to be one of the most promising for lattice oxygen transfer. In this study, CeO2 was used for splitting CO2 and H2O using concentrated solar energy with reaction temperatures in the range 900–1100 °C. The experimental studies in a solar-driven thermogravimetric system indicated that both CH4 induced reduction and CO2 induced oxidation of CeO2−δ followed close reaction orders with activation energies of 109 and 36 kJ mol–1, respectively. The results were compared with those obtained from hydrothermal templating and surfactant induced self-assembly. To our knowledge, such materials are studied for the first time for CH4 induced fuel production via solar thermochemical redox cycles. Enhanced reaction rates and stability upon cycling were observed for materials synthesized by hydrothermal and self-assembly methods. Experiments were also carried out to deduce the effect of various inert materials (MgO and Al2O3) as promotional agents. Higher reduction rate and maximum nonstoichiometry (δ = 0.431) during reduction at 1000 °C were observed in the case of MgO promoted CeO2. In addition, the amount of evolved CO was found to be the highest (δ = 0.402), indicating almost complete reoxidation. The achieved nonstoichiometry and the resulting fuel productivity are more than 10 times higher than the reported values for thermal reduction of ceria. Studies were also performed in a solar reactor prototype, enabling both partial ceria reduction with methane, followed by oxidation with H2O/CO2. Typically, MgO and Al2O3 promoted ceria were tested under packed bed conditions and compared with commercial ceria for syngas production. In this case, significant enhancement in the system efficiency was observed for MgO promoted CeO2.

show abstract

“…The reaction proceeds endothermically at above 1300 K and has been experimentally demonstrated using concentrated solar radiation as the energy source of process heat [2][3][4]. The solar chemical reactor design featured a packed bed of a ZnO-C mixture subjected to high-flux thermal irradiation and undergoing shrinking due to the carbothermic reduction.…”

Section: Introductionmentioning

confidence: 99%

Experimental Determination of the Extinction Coefficient for a Packed-Bed Particulate Medium

Osinga¹,

Lipiński²,

Guillot

et al. 2006

Experimental Heat Transfer

View full text Add to dashboard Cite

The extinction coefficient of a powder mixture of ZnO and beech charcoal is determined at ambient temperature using two experimental set-ups: (a) radiation in the range 500-1000 nm is captured by a 200 µm-diameter fiber optic and sent to a spectrometer equipped with a Si/PbSe detector; (b) radiation in the range 350-1100 nm is captured by a 5 mmdiameter Si-photodiode. Both set-ups measure the attenuation of intensity from a 3273 K blackbody source. The experimental results are implemented in the numerical solution of the equation of radiative transfer, using the Monte-Carlo ray-tracing technique. The extinction coefficient is determined to be 10103 ± 615 m −1 at 1000 nm using set up (a), and 7850 ± 337 m −1 for the range 350-1100 nm using the more accurate set-up (b).

show abstract

Experimental study of solar reactors for carboreduction of zinc oxide

Cited by 31 publications

References 8 publications

Enhanced Adsorption of Ammonia on Metal‐Organic Framework/Graphite Oxide Composites: Analysis of Surface Interactions

Enhanced Adsorption of Ammonia on Metal‐Organic Framework/Graphite Oxide Composites: Analysis of Surface Interactions

Tailoring Hybrid Nonstoichiometric Ceria Redox Cycle for Combined Solar Methane Reforming and Thermochemical Conversion of H₂O/CO₂

Experimental Determination of the Extinction Coefficient for a Packed-Bed Particulate Medium

Contact Info

Product

Resources

About

Experimental study of solar reactors for carboreduction of zinc oxide

Cited by 31 publications

References 8 publications

Enhanced Adsorption of Ammonia on Metal‐Organic Framework/Graphite Oxide Composites: Analysis of Surface Interactions

Enhanced Adsorption of Ammonia on Metal‐Organic Framework/Graphite Oxide Composites: Analysis of Surface Interactions

Tailoring Hybrid Nonstoichiometric Ceria Redox Cycle for Combined Solar Methane Reforming and Thermochemical Conversion of H2O/CO2

Experimental Determination of the Extinction Coefficient for a Packed-Bed Particulate Medium

Contact Info

Product

Resources

About

Tailoring Hybrid Nonstoichiometric Ceria Redox Cycle for Combined Solar Methane Reforming and Thermochemical Conversion of H₂O/CO₂