Elucidating and exploiting the chemistry of Keggin heteropolyacids in the methanol-to-DME conversion: enabling the bulk reaction thanks to operando Raman

2017 ◽  
Vol 7 (4) ◽  
pp. 817-830 ◽  
Author(s):  
Josefine Schnee ◽  
Eric M. Gaigneaux
Keyword(s):  
Bulk Reaction ◽  
Keggin Heteropolyacids

To activate an HPA's bulk in the methanol-to-DME reaction: 1) dehydrate it, 2) pre-expose it to methanol at 25 °C.

Synthesis of Aliphatic-Aromatic Copolyesters by a Melting Bulk Reaction Between Poly(butylene terephthalate) and DL-Oligo(lactic acid)

2007 ◽  
Vol 20 (2) ◽  
pp. 166-184 ◽  
Author(s):  
Xiang Jun Zhu ◽  
Yiwang Chen ◽  
Jiying Suxiaohui He ◽  
Licheng Tan ◽  
Yang Wang
Keyword(s):  
Lactic Acid ◽  
Butylene Terephthalate ◽  
Bulk Reaction

Vibrational disequilibrium in bulk reaction systems

1977 ◽  
Vol 49 (2) ◽  
pp. 338-342 ◽  
Author(s):  
Tadeusz Kleindienst ◽  
Edward J. Bair
Keyword(s):  
Reaction Systems ◽  
Bulk Reaction

Investigation of chlorine wall decay in an old, decommissioned metallic pipe using a pipe section reactor

2020 ◽  
Vol 20 (3) ◽  
pp. 953-962
Author(s):  
R. Tonev ◽  
G. Dimova
Keyword(s):  
Reaction Rate ◽  
Rate Coefficient ◽  
Tap Water ◽  
Decay Rates ◽  
Free Chlorine ◽  
Reaction Rate Coefficient ◽  
Pipe Section ◽  
Reaction Coefficient ◽  
Bulk Reaction ◽  
Series Of Experiments

Abstract The study investigates the kinetics of free chlorine depletion in tap water from the Sofia distribution network. The overall decay rates, the bulk reaction rate coefficient, the wall reaction rate coefficient and the influence of mass transfer have been determined in a laboratory pipe section reactor (PSR), testing an old decommissioned metallic pipe. In total, 23 series of experiments were performed under different initial free chlorine concentrations and different hydraulic conditions. The applicability of different chlorine decay mathematical models has been investigated. A new model was proposed, combining zero order bulk reactions and first order wall reactions, describing the laboratory results with Nash-Sutcliffe efficiency coefficients over 0.99. The obtained values for the wall reaction coefficient vary in the range 0.008–0.030 m/h, decreasing exponentially with increasing initial chlorine concentration.

Efficient Tetrahydropyranylation of Phenols and Alcohols Catalyzed by Supported Mo and W Keggin Heteropolyacids

2003 ◽  
Vol 33 (8) ◽  
pp. 1359-1365 ◽  
Author(s):  
G. P. Romanelli ◽  
P. G. Vázquez ◽  
L. R. Pizzio ◽  
C. V. Cáceres ◽  
M. N. Blanco ◽  
...  
Keyword(s):  
Keggin Heteropolyacids

Reprocessing Silicon Carbide Inert Matrix Fuel by Molten Salt Corrosion

2009 ◽  
Vol 1215 ◽  
Author(s):  
Ting Cheng ◽  
Ronald Baney ◽  
James Tulenko
Keyword(s):  
Silicon Carbide ◽  
Matrix Material ◽  
Water Soluble ◽  
Inert Matrix Fuel ◽  
Inert Matrix ◽  
Molten Carbonates ◽  
Air Atmosphere ◽  
Salt Corrosion ◽  
Bulk Reaction ◽  
Inert Matrix Fuels

AbstractSilicon carbide is one of the prime matrix material candidates for inert matrix fuels (IMF) which are being designed to reduce plutonium and long half-life actinide inventories through transmutation. Since complete transmutation is impractical in a single in-core run, reprocessing the inert matrix fuels becomes necessary. The current reprocessing techniques of many inert matrix materials involve dissolution of spent fuels in acidic aqueous solutions. However, SiC cannot be dissolved by that process. Thus, new reprocessing techniques are required.This paper discusses a possible way for separating transuranic (actinide) species from a bulk silicon carbide (SiC) matrix utilizing molten carbonates. Bulk reaction-bonded SiC and SiC powder (1 μm) were corroded at high temperatures (above 850 °C) in molten carbonates (K2CO3 and Na2CO3) in an air atmosphere to form water soluble silicates. Separation of Ceria (used as a surrogate for the plutonium fissile fuel) was achieved by dissolving the silicates in boiling water and leaving behind the solid ceria (CeO2).

Enhancement of levoglucosan production via fast pyrolysis of sugarcane bagasse by pretreatment with Keggin heteropolyacids

2020 ◽  
Vol 154 ◽  
pp. 112680 ◽  
Author(s):  
Milena Galdino Teixeira ◽  
Sarah de Paiva Silva Pereira ◽  
Sergio Antonio Fernandes ◽  
Márcio José da Silva
Keyword(s):  
Sugarcane Bagasse ◽  
Fast Pyrolysis ◽  
Keggin Heteropolyacids

Shock-induced reaction synthesis (SRS) of nickel aluminides

1992 ◽  
Vol 7 (5) ◽  
pp. 1063-1075 ◽  
Author(s):  
N.N. Thadhani ◽  
S. Work ◽  
R.A. Graham ◽  
W.F. Hammetter
Keyword(s):  
Plastic Flow ◽  
Chemical Reactions ◽  
Shock Loading ◽  
Nickel Aluminides ◽  
Synthesis Process ◽  
Reaction Synthesis ◽  
Aluminum Powders ◽  
Bulk Reaction ◽  
Phase Compound ◽  
Induced Reaction

Shock-induced chemical reactions between nickel and aluminum powders (mixed in Ni3Al stoichiometry) are used for the synthesis of nickel aluminides. It is shown that the extent of shock-induced chemical reactions and the nature of the shock-synthesized products are influenced by the morphology of the starting powders. Irregular (flaky type) and fine morphologies of the powders undergo complete reactions in contrast to partial reactions occurring in coarse and uniform morphology powders under identical shock loading conditions. Furthermore, irregular morphology powders result in the formation of the equiatomic (B2 phase) NiAl compound while the Ni3Al (L12 phase) compound is the reaction product with coarse and regular morphology powders. Shock-induced reaction synthesis can be characterized as a bulk reaction process involving an intense “mechanochemical” mechanism. It is a process in which shock compression induces fluid-like plastic flow and mixing, and enhances the reactivity due to the introduction of defects and cleansing of particle surfaces, which strongly influence the synthesis process.

scholarly journals Synthesis and Study of CdSe QDs by a Microfluidic Method and via a Bulk Reaction

Crystals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 368 ◽  
Author(s):  
Jinfeng Liu ◽  
Yarong Gu ◽  
Qirui Wu ◽  
Xiaohong Wang ◽  
Lijuan Zhao ◽  
...  
Keyword(s):  
Growth Process ◽  
Crystal Growth Rate ◽  
Cdse Quantum Dots ◽  
Residence Times ◽  
Cdse Qds ◽  
Visible Absorption ◽  
X Ray ◽  
Transmission Electron ◽  
Bulk Reaction ◽  
Visible Absorption Spectroscopy

In this work, we synthesized monodispersed CdSe quantum dots (QDs) by a microfluidic method and via a bulk reaction. The structures of the CdSe QDs were characterized by X-ray powder diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). The optical properties of the prepared CdSe QDs were determined using ultraviolet-visible absorption spectroscopy and photoluminescence spectroscopy. The CdSe QDs obtained by the microfluidic method have a faster crystal growth rate and a higher absolute photoluminescence quantum yield than those obtained via the bulk reaction. Additionally, we investigated the growth process of the CdSe QDs with increasing residence times.

Sign in / Sign up

Export Citation Format

Share Document