Influence of the reaction time on the physical–chemical and catalytic properties of vanadium phosphate catalysts prepared by a eutectic mixture

2019 ◽  
Vol 14 (11) ◽  
pp. 1126-1130
Author(s):  
Qi Zhang ◽  
Weiguo Fang ◽  
Qian Li
Keyword(s):  
Reaction Time ◽  
Catalytic Properties ◽  
Eutectic Mixture ◽  
Vanadium Phosphate ◽  
Physical Chemical

scholarly journals PHYSICAL CHEMICAL STUDIES OF THE SURFACTANT DILAURYLDIMETHYLAMMONIUM BROMIDE (DLDMAB): AGGREGATION AND CATALYTIC PROPERTIES

2009 ◽  
Vol 17 (17) ◽  
pp. 21-32
Author(s):  
Elizabeth Fatima de Souza ◽  
Silvia Dani ◽  
Lavinel G. IONESCU
Keyword(s):  
Thermodynamic Parameters ◽  
Catalytic Properties ◽  
Activation Parameters ◽  
Critical Micellar Concentration ◽  
Physical Chemical ◽  
Chemical Studies ◽  
Diphenyl Phosphate ◽  
C 32 ◽  
Free Energy Of Micellization ◽  
Hydrolysis Of

The micellization of dilauryldimethylammonium bromide (DLDMAB) in water was studied by using surface tension measurements. The critical micellar concentration (CMC) was determined at 25°C, 32°C and 40°C and thermodynamic parameters such as the free energy of micellization (∆G°mic), enthalpy (∆H°mic), and entropy (∆S°mic) of micellization were measured. The CMC at 25°C was 4.93 x 10-5 M and the corresponding values of the thermodynamic parameters were: ∆G°mic = -5.87 kcal/mol; ∆H°mic = -1.12 kcal/mol and ∆S°mic = +16.00 e.u. Micelles of the surfactant DLDMAB act as catalysts for the alkaline hydrolysis of p-nitrophenyl diphenyl phosphate (NPDPP) with a maximum catalytic factor of approximately 120 compared to 80 for CTAB. Typical activation parameters measured for 1.00 x 10-3 M surfactant and 0.005 M NaOH were: Ea = 9.7 kcal/mo/; ∆H°≠ = 9.1 kcal/mol; ∆G°≠ = 19.6 kcal/mol and ∆S°≠ = -33.9 e.u. The kinetic results were also analyzed in terms of the pseudo-phase ion-exchange models (PPIE) and showed that the model is applicable to describe the experimental results.

Study on the Preparation of Nano-Cu2O and its Morphology Control

2011 ◽  
Vol 328-330 ◽  
pp. 1355-1358 ◽  
Author(s):  
Bin Zhao ◽  
Di Ma
Keyword(s):  
Room Temperature ◽  
Catalytic Properties ◽  
Chemical Properties ◽  
Morphological Structure ◽  
Morphology Control ◽  
Nano Particles ◽  
Preparation Methods ◽  
Physical Chemical ◽  
Application Fields ◽  
Application Prospects

Nano-Cu2O has wide application prospects in the fields of chemical industry and engineering due to its special optical, electrical and catalytic properties. The nano-particles with different morphological structure and particle size have different physical-chemical properties and different application fields. Therefore, this article reviewed the preparation methods of Nano-Cu2O at high/room temperature and the key point of its morphology control.

Selective Hydrogenation of p-Chloronitrobenzene Catalyzed by FexOY@C Supported Pt-Catalyst

2014 ◽  
Vol 960-961 ◽  
pp. 221-224
Author(s):  
Jie Wu ◽  
Guang Yin Fan ◽  
Wen Jun Huang
Keyword(s):  
Reaction Time ◽  
Selective Hydrogenation ◽  
Hydrogen Pressure ◽  
Room Temperature ◽  
Catalytic Properties ◽  
Pt Nanoparticles ◽  
Pt Catalyst ◽  
Water Mixture ◽  
Supported Pt Catalyst

FexOy@C nanocomposites were synthesized and used as carriers for depositing Pt nanoparticles. Catalytic properties of the nanocomposites were investigated for the hydrogenation of p-chloronitrobenzene at room temperature and balloon hydrogen pressure. The catalyst Pt/FexOy@C was extremely active for the hydrogenation of p-chloronitrobenzene. Completely conversion of p-chloronitrobenzene was achieved with a selectivity of 99.7 % in ethanol-water mixture in a reaction time of 40 min. Moreover, it can be reused four times without loss of any activity.

scholarly journals Karakteristik Fisik, Kimia, dan Fungsional Pati Ubi Banggai Asetat pada Berbagai Variasi Waktu Reaksi

2021 ◽  
Vol 40 (4) ◽  
pp. 340
Author(s):  
If'all If'all ◽  
Asriani Hasanuddin ◽  
Abdul Rahim ◽  
Syahraeni Kadir
Keyword(s):  
Reaction Time ◽  
Treatment Time ◽  
Reaction Times ◽  
Degree Of Substitution ◽  
Raw Material ◽  
Physical Chemical ◽  
Randomized Design ◽  
Substitution Degree ◽  
Completely Randomized Design ◽  
The One

Banggai yam plant (endemic in Banggai Kepulauan Regency) is a potential raw material in production of modified starch. The one of techniques to increase the value of starch is modification of starch by acetylation method. This study objectives to determine the physical, chemical and functional characteristics of Banggai acetate yam starch at various reaction times. The study used a Completely Randomized Design with treatment time reaction (T), namely T1: 30 min, T2: 35 min, T3: 40 min, T4: 45 min, T5: 50 min, T6: 55 min. This study was conducted to determine the characteristics of yam acetate starch, which includes percent acetyl, degree of substitution, water and oil holding capacity (WHC/OHC), flammability, solubility, moisture content, ash, fat, protein, starch and amylose starch. The results showed that the longer reaction time under certain conditions will increase the acetyl percent, degree of substitution, WHC, OHC, flareability, solubility but reduce levels of fat, water, ash, fat, protein, starch and amylose starch, yam acetate. In this study at the best reaction time is (50 min), gives the acetyl percent 8.658% and substitution degree of 0.356, the value of WHC, OHC, Swelling ratio and solubility of 32.21%, 30.21%, 1.98 g/g, and 19.17% respectively.

scholarly journals PHYSICAL CHEMICAL STUDIES OF THE AGGREGATION AND CATALYTIC PROPERTIES OF THE SURFACTANT CETYLDIMETHYLETHYLAMMONIUM BROMIDE (CDEAB)

1999 ◽  
Vol 7 (8) ◽  
pp. 105-114
Author(s):  
Lavinel G. Ionescu ◽  
Silvia Dani ◽  
Elizabeth Fatima de Souza
Keyword(s):  
Free Energy ◽  
Catalytic Properties ◽  
Activation Parameters ◽  
Critical Micellar Concentration ◽  
Physical Chemical ◽  
Chemical Studies ◽  
Diphenyl Phosphate ◽  
Free Energy Of Micellization ◽  
Surface Tensiometry ◽  
Hydrolysis Of

The micellization of cetyldimethylethylammonium bromide (CDEAB) in water was studied by means of surface tensiometry. The critical micellar concentration (CMC) was determined at 25°, 32°, and 40°C, and thermodynamic properties such as the free energy of micellization (∆G°mic), enthalpy (∆H°mic) and entropy (∆S°mic) of micellization were measured. The CMC at 25°C was 9.05 x 10-4 M and the corresponding values of the thermodynamic parameters were: ∆G°mic = -4.15 kcal/mol; ∆H°mic = -1.37 kcal/mol and ∆S°mic = + 9.33 e.u. Micelles of the surfactant CDEAB were good catalysts for the alkaline hydrolysis of p-nitrophenyl diphenyl phosphate (NPDPP) with a maximum catalytic factor of approximately 80, comparable to that of CTAB. Typical activation parameters measured for 0.005 M NaOH were: Ea = 9.0 kcal/mol; ∆H°≠ = 8.4 kcal/mol; ∆G°≠ = 19.2 kcal/mol and ∆S°≠ = -36.3 e.u. The kinetic results were also analyzed in terms of the pseudo-phase ion-exchange models (PPIE) and showed that the model is applicable and gave reasonable fits

scholarly journals Influence of Milling Media on the Physicochemicals and Catalytic Properties of Mechanochemical Treated Vanadium Phosphate Catalysts

2010 ◽  
Vol 141 (3) ◽  
pp. 400-407 ◽  
Author(s):  
Y. H. Taufiq-Yap ◽  
C. K. Goh ◽  
G. J. Hutchings ◽  
N. Dummer ◽  
J. K. Bartley
Keyword(s):  
Catalytic Properties ◽  
Vanadium Phosphate

Rabbit liver transglutaminase: physical, chemical, and catalytic properties

Biochemistry ◽  
1977 ◽  
Vol 16 (25) ◽  
pp. 5495-5501 ◽  
Author(s):  
Takashi Abe ◽  
Soo Il Chun ◽  
Richard P. DiAugustine ◽  
J. E. Folk
Keyword(s):  
Catalytic Properties ◽  
Rabbit Liver ◽  
Physical Chemical
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