Synthesis of 3-tert-butylaniline by Using Hydrodechlorination Technology

2014 ◽  
Vol 1051 ◽  
pp. 125-129
Author(s):  
Chong Long Li
Keyword(s):  
Catalytic Activity ◽  
Raney Nickel ◽  
Ammonium Acetate ◽  
High Catalytic Activity ◽  
Waste Streams ◽  
Catalytic Hydrodechlorination ◽  
Tert Butyl ◽  
Raney Nickel Catalyst ◽  
Reaction Solution ◽  
Temperature And Pressure

Catalytic hydrodechlorination (HDC) is an innovative means of transforming chlorinated waste streams into a recyclable product. Hydrodehalogenation of 4-tert-butyl-1-chloro-2-nitrobenzene over Raney nickel catalyst has been investigated. The influence of different parameters, such as reaction solution, bases type, temperature and pressure are explored. Using Raney nickel as catalyst, methanol and water (v: v=4:1) as the reaction solution, ammonium acetate as the addictive, the ratio of ammonium acetate and 4-tert-butyl-1-chloro-2-nitrobenzene is 1:1, temperature 140 °C and pressure 3.0 Mpa, the highest efficiency can be achieved on hydride-chlorination of 4-tert-butyl-1-chloro-2-nitrobenzene. We find that a rather high catalytic activity can be retained by adding water.

Oxovanadium(IV), Nickel(II) and Palladium(II) Complexes of Tridentate Salicylaldiminates Derived from 2,4-Di-ter-butyl-6-aminophenol

2001 ◽  
Vol 56 (3) ◽  
pp. 263-270 ◽  
Author(s):  
Veli T. Kasumov
Keyword(s):  
Catalytic Activity ◽  
Room Temperature ◽  
High Catalytic Activity ◽  
Tert Butyl ◽  
Preliminary Activation

Abstract Several new binuclear nickel(II), oxovanadium(IV) and palladium(II) complexes (MLX) of tridentate salicylaldimines (LXH2) obtained from substituted salicylaldehydes and 2,4-di-tert-butyl-6-aminophenol, as well as mononuclear nickel(II) and oxovanadium(IV), MQx nH2O, complexes with hydrogenated LX H2 ligands (QXH2) have been prepared and their spectroscopic, magnetic and catalytic activity (for PdLx) have been investigated. NiLx and VOLx complexes when dissolved in pyridine, take up three or two pyridine molecules to form six coordinated complexes, respectively. The Ni(II) and VO(IV) complexes obtained from QXH2 can be formu­lated as NiQx-3H2O and VOQx H2O. All VO(IV) complexes have been characterized by ESR parameters. It has been found that some PdLx complexes without any preliminary activation, in EtOH, THF and DMF exhibit high catalytic activity in the hydrogenation of nitrobenzene or cyclohexene at room temperature and at 30 -40 °C under 760 torr H2. When this reaction has been carried out in the ESR cavity at room temperature the triplet of 12 line multiplets due to the nitroxyl type coordinated radical (g = 2.013, AN = 10 G, AH = 0.8 G) was detected.

Friedel-Crafts Alkylation of Mesitylene with tert-Butyl Alcohol over Novel Solid Acid Catalyst UDCaT-5

2009 ◽  
Vol 7 (1) ◽  
Author(s):  
Ganapati D. Yadav ◽  
Shashikant B Kamble
Keyword(s):  
Catalytic Activity ◽  
Sulfated Zirconia ◽  
Reaction Pathway ◽  
Solid Acid Catalyst ◽  
Butyl Alcohol ◽  
High Catalytic Activity ◽  
Order Kinetic ◽  
Tert Butyl ◽  
Tert Butanol ◽  
Tert Butyl Alcohol

Alkylation of mesitylene with tert-butyl alcohol in the presence of novel mesoporous superacidic catalysts, namely, UDCaT-4, UDCaT-5 and UDCaT-6 was investigated. The catalysts are modified versions of zirconia showing high catalytic activity, stability and reusability in the presence of water as compared to conventional sulfated zirconia. The catalytic activity is in the order: UDCaT-5 (most active) > UDCaT-6 > UDCaT-4 > sulfated zirconia (S-ZrO2) (least active). The synergistic effect of the very high sulfur content present (9% w/w S) and the preservation of the tetragonal phase in UDCaT-5, in comparison with sulfated zirconia (4% w/w S), were responsible for higher catalytic activity. A catalyst ensuring the production of 2-tert-butyl-mesitylene (2-TBMT) with 98% selectivity and 94% conversion of tert-butanol (TBA) was developed under optimum reaction conditions. The formation of products is correlated with the acidity of the catalyst. The reactions were conducted in liquid phase at relatively low reaction temperatures (120–150 °C). A systematic investigation of the effects of various operating parameters was accomplished and a mathematical model is developed to describe the reaction pathway and validated with experimental results. The reaction was carried out without using any solvent in order to make the process cleaner and greener. An overall second order kinetic equation was used to fit the experimental data, under the assumption that both mesitylene and tert-butanol are weakly adsorbed. An independent dehydration study of tert-butanol (TBA) was also done.

scholarly journals Improved Performance of D-Psicose 3-Epimerase by Immobilisation on Amino-Epoxide Support with Intense Multipoint Attachment

Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 831
Author(s):  
Yifan Bu ◽  
Tao Zhang ◽  
Bo Jiang ◽  
Jingjing Chen
Keyword(s):  
Catalytic Activity ◽  
Ion Exchange ◽  
Substrate Specificity ◽  
Covalent Binding ◽  
Residual Activity ◽  
Free Form ◽  
High Catalytic Activity ◽  
Low Calorie ◽  
Reaction Solution ◽  
Improved Performance

D-allulose is an epimer of D-fructose at the C-3 position. With similar sweetness to sucrose and a low-calorie profile, D-allulose has been considered a promising functional sweetener. D-psicose 3-epimerase (DPEase; EC 5.1.3.30) catalyses the synthesis of D-allulose from D-fructose. Immobilised enzymes are becoming increasingly popular because of their better stability and reusability. However, immobilised DPEase generally exhibits less activity or poses difficulty in separation. This study aimed to obtain immobilised DPEase with high catalytic activity, stability, and ease of separation from the reaction solution. In this study, DPEase was immobilised on an amino-epoxide support, ReliZyme HFA403/M (HFA), in four steps (ion exchange, covalent binding, glutaraldehyde crosslinking, and blocking). Glycine-blocked (four-step immobilisation) and unblocked (three-step immobilisation) immobilised DPEase exhibited activities of 103.5 and 138.8 U/g support, respectively, but contained equal amounts of protein. After incubation at 60 °C for 2 h, the residual activity of free enzyme decreased to 12.5%, but the activities of unblocked and blocked DPEase remained at 40.9% and 52.3%, respectively. Immobilisation also altered the substrate specificity of the enzyme, catalysing L-sorbose to L-tagatose and D-tagatose to D-sorbose. Overall, the immobilised DPEase with intense multipoint attachment, especially glycine-blocked DPEase, showed better properties than the free form, providing a superior potential for D-allulose biosynthesis.

scholarly journals Synthesis and catalytic properties of iron - cerium phosphates with surfactant

Cerâmica ◽  
2013 ◽  
Vol 59 (349) ◽  
pp. 165-169
Author(s):  
H. Onoda ◽  
T. Sakumura
Keyword(s):  
Catalytic Activity ◽  
Ammonium Acetate ◽  
Catalytic Properties ◽  
Iron Phosphate ◽  
Laser Diffraction ◽  
High Catalytic Activity ◽  
Diffraction Scattering ◽  
Sem Images ◽  
Xrd Patterns ◽  
Dodecyl Ether

Iron phosphate was prepared from iron nitrate and phosphoric acid with a surfactant, pentaethylene glycol mono dodecyl ether. The chemical composition of the obtained samples was estimated from ICP and XRD measurements. Particle shape and size distribution were observed by SEM images and laser diffraction / scattering methods. Further, the catalytic activity was studied with the decomposition of the complex between formaldehyde, ammonium acetate, and acetylacetone. The peaks of FePO4 were observed in XRD patterns of samples prepared in Fe/Ce=10/0 and then heated at 600 ºC. Other samples were amorphous in XRD patterns. Iron-cerium phosphates had high catalytic activity for the decomposition of the complex.

scholarly journals Preparation and Catalytic Properties of Iron-Cerium Phosphates with Sodium Dodecyl Sulfate

ISRN Ceramics ◽  
2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Hiroaki Onoda ◽  
Takeshi Sakumura
Keyword(s):  
Catalytic Activity ◽  
Sodium Dodecyl Sulfate ◽  
Ammonium Acetate ◽  
Catalytic Properties ◽  
Sodium Dodecyl ◽  
Iron Phosphate ◽  
High Catalytic Activity ◽  
Sem Images ◽  
Dodecyl Sulfate ◽  
Xrd Patterns

Iron phosphate was prepared from iron nitrate and phosphoric acid with sodium dodecyl sulfate at various stirring hours. The chemical composition of the obtained samples was estimated from ICP and XRD measurements. Particle shape and size distribution were observed by SEM images and laser diffraction/scattering methods. Further, the catalytic activity was studied with the decomposition of the complex between formaldehyde, ammonium acetate, and acetylacetone. The peaks of FePO4 were observed in XRD patterns of samples prepared in Fe/Ce = 10/0 and then heated at 600°C. Other samples were amorphous in XRD patterns. Iron-cerium phosphates had high catalytic activity for the decomposition of the complex.

Enhanced catalytic activity of low-Pt content nanocatalysts supported on hollow carbon spheres for the ORR in alkaline media

MRS Advances ◽  
2020 ◽  
Vol 5 (57-58) ◽  
pp. 2961-2972
Author(s):  
P.C. Meléndez-González ◽  
E. Garza-Duran ◽  
J.C. Martínez-Loyola ◽  
P. Quintana-Owen ◽  
I.L. Alonso-Lemus ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Anion Exchange ◽  
Average Particle Size ◽  
Synthesis Method ◽  
Alkaline Media ◽  
High Catalytic Activity ◽  
Average Particle ◽  
Carbon Spheres ◽  
Hollow Carbon ◽  
Hollow Carbon Spheres

In this work, low-Pt content nanocatalysts (≈ 5 wt. %) supported on Hollow Carbon Spheres (HCS) were synthesized by two routes: i) colloidal conventional polyol, and ii) surfactant-free Bromide Anion Exchange (BAE). The nanocatalysts were labelled as Pt/HCS-P and Pt/HCS-B for polyol and BAE, respectively. The physicochemical characterization of the nanocatalysts showed that by following both methods, a good control of chemical composition was achieved, obtaining in addition well dispersed nanoparticles of less than 3 nm TEM average particle size (d) on the HCS. Pt/HCS-B contained more Pt0 species than Pt/HCS-P, an effect of the synthesis method. In addition, the structure of the HCS remains more ordered after BAE synthesis, compared to polyol. Regarding the catalytic activity for the Oxygen Reduction Reaction (ORR) in 0.5 M KOH, Pt/HCS-P and Pt/HCS-B showed a similar performance in terms of current density (j) at 0.9 V vs. RHE than the benchmark commercial 20 wt. % Pt/C. However, Pt/HCS-P and Pt/HCS-B demonstrated a 6 and 5-fold increase in mass catalytic activity compared to Pt/C, respectively. A positive effect of the high specific surface area of the HCS and its interactions with metal nanoparticles and electrolyte, which promoted the mass transfer, increased the performance of Pt/HCS-P and Pt/HCS-B. The high catalytic activity showed by Pt/HCS-B and Pt/HCS-P for the ORR, even with a low-Pt content, make them promising cathode nanocatalysts for Anion Exchange Membrane Fuel Cells (AEMFC).

Ordered Intermetallic Nanoparticles with High Catalytic Activity Prepared by an Electrochemically Induced Phase Transformation

2019 ◽  
Author(s):  
Du Sun ◽  
yunfei wang ◽  
Kenneth Livi ◽  
chuhong wang ◽  
ruichun luo ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Diffusion Mechanism ◽  
Reduction Reaction ◽  
Atomic Scale ◽  
High Catalytic Activity ◽  
Ambient Conditions ◽  
Magnetic Devices ◽  
Disordered Alloys ◽  
Ordered Intermetallic ◽  
Intermetallic Nanoparticles

<div> <p>The synthesis of alloys with long range atomic scale ordering (ordered intermetallics) is an emerging field of nanochemistry. Ordered intermetallic nanoparticles are useful for a wide variety of applications such as catalysis, superconductors, and magnetic devices. However, the preparation of nanostructured ordered intermetallics is challenging in comparison to disordered alloys, hindering progress in materials development. We report a process for converting colloidally synthesized ordered intermetallic PdBi<sub>2</sub> to ordered intermetallic Pd<sub>3</sub>Bi nanoparticles under ambient conditions by an electrochemically induced phase transition. The low melting point of PdBi<sub>2</sub> corresponds to low vacancy formation energies which enables the facile removal of the Bi from the surface, while simultaneously enabling interdiffusion of the constituent atoms via a vacancy diffusion mechanism under ambient conditions. The resulting phase-converted ordered intermetallic Pd<sub>3</sub>Bi exhibits 11x and 3.5x higher mass activty and high methanol tolerance for the oxygen reduction reaction compared to Pt/C and Pd/C, respectively,which is the highest reported for a Pd-based catalyst, to the best of our knowledge. These results establish a key development in the synthesis of noble metal rich ordered intermetallic phases with high catalytic activity, and sets forth guidelines for the design of ordered intermetallic compounds under ambient conditions.</p> </div>

Nickel (II) and oxovanadium (IV) complexes supported on MCM-41 mesoporous and their application in catalytic selective sulfide and thiol oxidation

2020 ◽  
Vol 23 ◽  
Author(s):  
Mohsen Nikoorazm ◽  
Maryam Khanmoradi ◽  
Masoumeh Sayadian
Keyword(s):  
Catalytic Activity ◽  
Room Temperature ◽  
Sol Gel ◽  
Reaction Times ◽  
Significant Loss ◽  
Spectral Studies ◽  
High Catalytic Activity ◽  
Catalytic Systems ◽  
Solvent Free Conditions ◽  
Mcm 41

Introduction:: MCM-41 was synthesized using the sol-gel method. Then two new transition metal complexes of Nickel (II) and Vanadium (IV), were synthesized by immobilization of adenine (6-aminopurine) into MCM-41 mesoporous. The compounds have been characterized by XRD, TGA, SEM, AAS and FT-IR spectral studies. Using these catalysts provided an efficient and enantioselective procedure for oxidation of sulfides to sulfoxides and oxidative coupling of thiols to their corresponding disulfides using hydrogen peroxide at room temperature. Materials and Methods:: To a solution of sulfide or thiol (1 mmol) and H2O2 (5 mmol), a determined amount of the catalyst was added. The reaction mixture was stirred at room temperature for the specific time under solvent free conditions. The progress of the reaction was monitored by TLC using n-hexane: acetone (8:2). Afterwards, the catalyst was removed from the reaction mixture by centrifugation and, then, washed with dichloromethane in order to give the pure products. Results:: All the products were obtained in excellent yields and short reaction times indicating the high activity of the synthesized catalysts. Besides, the catalysts can be recovered and reused for several runs without significant loss in their catalytic activity. Conclusion:: These catalytic systems furnish the products very quickly with excellent yields and VO-6AP-MCM-41 shows high catalytic activity compared to Ni-6AP-MCM-41.

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