Aqueous-phase ketonization of acetic acid over Ru/TiO2/carbon catalysts

2012 ◽  
Vol 295 ◽  
pp. 169-178 ◽  
Author(s):  
Tu Nguyet Pham ◽  
Dachuan Shi ◽  
Tawan Sooknoi ◽  
Daniel E. Resasco
Keyword(s):  
Acetic Acid ◽  
Aqueous Phase ◽  
Carbon Catalysts

EUROPIUM OXALATE ION ASSOCIATION IN WATER

1966 ◽  
Vol 44 (24) ◽  
pp. 3057-3062 ◽  
Author(s):  
P. G. Manning
Keyword(s):  
Acetic Acid ◽  
Ionic Strength ◽  
Stability Constant ◽  
Stability Constants ◽  
Aqueous Phase ◽  
Sodium Acetate ◽  
Ion Association ◽  
Sodium Oxalate ◽  
Aqueous Sodium ◽  
Oxalate Ion

The partitioning of radiotracer 152/151Eu between aqueous sodium oxalate (Na2L) solutions and toluene solutions of thenoyltrifluoroacetone (HTTA) has been studied as a function of the oxalate concentration. The pH of the aqueous phase was controlled by means of sodium acetate – acetic acid mixtures and the ionic strength (I) by NaCl or NaClO4.At low ionic strengths (~0.05) and [L] ~10−4 M EuL+ formed, but at I = 0.95 and [L] ~10−3 M EuL2− also formed. Stability constants for the 1:1 and 1:2 (metal:ligand) complexes are reported.The magnitudes of the stepwise stability constant ratios are discussed.

Comparative Salmonella Spp. and Listeria monocytogenes Inactivation Rates in Four Commercial Mayonnaise Products

1991 ◽  
Vol 54 (12) ◽  
pp. 913-916 ◽  
Author(s):  
JOHN P. ERICKSON ◽  
PHYLLIS JENKINS
Keyword(s):  
Acetic Acid ◽  
Listeria Monocytogenes ◽  
Aqueous Phase ◽  
Population Declines ◽  
Salmonella Spp ◽  
Egg White Lysozyme ◽  
Consumer Safety ◽  
Safety Risks ◽  
Broad Cross Section ◽  
Formula Composition

Salmonella spp. and Listeria monocytogenes strains were inoculated into four commercial mayonnaise products: sandwich spread, real mayonnaise, reduced calorie mayonnaise dressing, and cholesterol-free reduced calorie mayonnaise dressing. Products represented a broad cross-section of aqueous phase acetic acid, salt, sucrose, and other compositional factors. Results showed that Salmonella spp. inactivation rates were unaffected by formula composition. The organism was rapidly inactivated, decreasing ≥8 log10 CFU/g in ≤72 h, in each of the four products. L. monocytogenes inactivation rates were directly correlated with aqueous phase acetic acid concentrations as follows: sandwich spread ≥ real mayonnaise > cholesterol-free reduced calorie mayonnaise dressing > reduced calorie mayonnaise dressing. L. monocytogenes inactivation rate in sandwich spread and real mayonnaise was similar to Salmonella spp. The reduced calorie mayonnaise dressings showed gradual, incremental population declines. L. monocytogenes decreased 3 and 5 log10 CFU/g in 72 h in reduced calorie and cholesterol-free reduced calorie mayonnaise dressings, respectively. The higher anti-listerial activity in the cholesterol free formulation was attributed to egg white lysozyme. This study documented that commercial mayonnaise, including reduced calorie mayonnaise dressing varieties, represent negligible consumer safety risks.

Ru decorated carbon nanotubes – a promising catalyst for reforming bio-based acetic acid in the aqueous phase

2014 ◽  
Vol 16 (2) ◽  
pp. 864 ◽  
Author(s):  
D. J. M. de Vlieger ◽  
L. Lefferts ◽  
K. Seshan
Keyword(s):  
Carbon Nanotubes ◽  
Acetic Acid ◽  
Aqueous Phase

scholarly journals STEAM REFORMING OF UPGRADED BIO-OIL AQUEOUS PHASE FRACTION FROM SUNFLOWER SEED HULLS: THERMODYNAMIC ANALYSIS

2019 ◽  
Vol 49 (4) ◽  
pp. 297-302
Author(s):  
Yanina P. Maidana ◽  
Eduardo Izurieta ◽  
Andres I. Casoni ◽  
Maria A. Volpe ◽  
Eduardo Lopez ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Aqueous Phase ◽  
Thermodynamic Analysis ◽  
Steam Reforming ◽  
Sunflower Seed ◽  
Maximum Yield ◽  
Energetic Efficiency ◽  
Water Addition ◽  
Thermal Requirements ◽  
Bio Oil

This work focuses on the study of hydrogen production process departing from waste lignocellulosic biomass. The bio-oil was first obtained by non-catalytic fast pyrolysis of sunflower seed hulls. Subsequently, it was upgraded to reduce the concentration of higher molecular weight compounds by water addition and mixing. A 1/1 bio-oil:water ratio was selected here. Later, a thermodynamic analysis based on free energy minimization was profited to study the steam reforming process of the upgraded bio-oil sample. The influence of the operation temperature on the reforming was analyzed. The highest hydrogen yields were obtained at ~740°C. A comparison with acetic acid used as model compound of the bio-oil is included. Results show that acetic acid is not a good approximation of a real aqueous phase of upgraded bio oil fraction. The study concludes with an analysis on the energetic efficiency, showing that its maximum is presented at lower temperatures than the maximum yield, due to the thermal requirements of preheating.

Aqueous phase conversion of CO2 into acetic acid over thermally transformed MIL-88B

2021 ◽  
Author(s):  
Waqar Ahmad ◽  
Paramita Koley ◽  
Swarit Dwivedi ◽  
Abhijit Shrotri ◽  
Akshat Tanksale
Keyword(s):  
Acetic Acid ◽  
Aqueous Phase ◽  
Carbon Emissions ◽  
Active Sites ◽  
Catalyst Recycling ◽  
Efficient Catalyst ◽  
Co Catalyst ◽  
Net Zero ◽  
Significant Difference ◽  
Zero Carbon

Abstract Sustainable production of acetic acid (AA) is a high priority due to its high global manufacturing capacity and numerous applications. Currently it is predominantly synthesized via carbonylation of methanol, in which both the reactants are fossil-derived. CO2 transformation into AA is highly desirable to achieve net zero carbon emissions, but significant challenges remain to achieve this efficiently. Herein, we report a heterogeneous catalyst, thermally transformed MIL-88B with Fe0 and Fe3O4 dual active sites, for highly selective AA formation via methanol hydrocarboxylation. This efficient catalyst showed high AA yield (590.1 mmol/gcat.L) with 81.7% selectivity at 150°C in aqueous phase using LiI as a co-catalyst. The reaction is believed to proceed via formic acid intermediate. No significant difference in AA yield and selectivity was noticed during catalyst recycling study up to five cycles. This work scalable and industrially relevant for CO2 utilisation to reduce carbon emissions, especially if green methanol and green hydrogen are used.

Aqueous Phase Hydrogenation of Acetic Acid and Its Promotional Effect on p-Cresol Hydrodeoxygenation

2012 ◽  
Vol 27 (1) ◽  
pp. 487-493 ◽  
Author(s):  
Haijun Wan ◽  
Raghunath V. Chaudhari ◽  
Bala Subramaniam
Keyword(s):  
Acetic Acid ◽  
Aqueous Phase ◽  
Promotional Effect

scholarly journals Chemical insights, explicit chemistry, and yields of secondary organic aerosol from OH radical oxidation of methylglyoxal and glyoxal in the aqueous phase

2013 ◽  
Vol 13 (17) ◽  
pp. 8651-8667 ◽  
Author(s):  
Y. B. Lim ◽  
Y. Tan ◽  
B. J. Turpin
Keyword(s):  
Acetic Acid ◽  
Aqueous Phase ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Oxidation Products ◽  
Radical Reactions ◽  
Organic Radical ◽  
Oh Radical ◽  
Radical Oxidation

Abstract. Atmospherically abundant, volatile water-soluble organic compounds formed through gas-phase chemistry (e.g., glyoxal (C2), methylglyoxal (C3), and acetic acid) have great potential to form secondary organic aerosol (SOA) via aqueous chemistry in clouds, fogs, and wet aerosols. This paper (1) provides chemical insights into aqueous-phase OH-radical-initiated reactions leading to SOA formation from methylglyoxal and (2) uses this and a previously published glyoxal mechanism (Lim et al., 2010) to provide SOA yields for use in chemical transport models. Detailed reaction mechanisms including peroxy radical chemistry and a full kinetic model for aqueous photochemistry of acetic acid and methylglyoxal are developed and validated by comparing simulations with the experimental results from previous studies (Tan et al., 2010, 2012). This new methylglyoxal model is then combined with the previous glyoxal model (Lim et al., 2010), and is used to simulate the profiles of products and to estimate SOA yields. At cloud-relevant concentrations (~ 10−6 − ~ 10−3 M; Munger et al., 1995) of glyoxal and methylglyoxal, the major photooxidation products are oxalic acid and pyruvic acid, and simulated SOA yields (by mass) are ~ 120% for glyoxal and ~ 80% for methylglyoxal. During droplet evaporation oligomerization of unreacted methylglyoxal/glyoxal that did not undergo aqueous photooxidation could enhance yields. In wet aerosols, where total dissolved organics are present at much higher concentrations (~ 10 M), the major oxidation products are oligomers formed via organic radical–radical reactions, and simulated SOA yields (by mass) are ~ 90% for both glyoxal and methylglyoxal. Non-radical reactions (e.g., with ammonium) could enhance yields.

Hydrogenation of phenol in aqueous phase with palladium on activated carbon catalysts

2007 ◽  
Vol 131 (1-3) ◽  
pp. 65-71 ◽  
Author(s):  
E. Díaz ◽  
A.F. Mohedano ◽  
L. Calvo ◽  
M.A. Gilarranz ◽  
J.A. Casas ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Aqueous Phase ◽  
Carbon Catalysts
Sign in / Sign up

Export Citation Format

Share Document