Application of activated carbon supported cobalt(II) tetraaminophthalocyanine towards preparation of dimethyl disulfide

2019 ◽  
Vol 23 (03) ◽  
pp. 267-278
Author(s):  
Zhiliang Cheng ◽  
Mingxing Dai ◽  
Xuejun Quan ◽  
Shuo Li ◽  
Daomin Zheng ◽  
...  

Dimethyl disulfide (DMDS) is an important fine chemical that can be prepared by the refined Merox process of oxidation of sodium methyl mercaptide (SMM) in the presence of a catalyst. In this paper, a novel activated carbon (AC) supported cobalt(II) tetraaminophthalocyanine (AC-CoTAPc) catalyst was prepared by the chemical grafting method. EA, UV-vis, FT-IR, BET and XPS were used to characterize the structure of the new catalyst. The effects of reaction time, catalyst dosage, reaction temperature and oxygen pressure on SMM conversion per pass (CPP[Formula: see text], yield (Yield[Formula: see text] and purity of DMDS product (Purity[Formula: see text] were investigated to evaluate the catalytic performance of new AC-CoTAPc catalyst. The results show that free CoTAPc is easily dissolved in this DMDS product, which needs extra post treatment and cannot be reused. The supported catalyst AC-CoTAPc can easily solve these problems and can be properly reused four times to get Yield[Formula: see text] and CPP[Formula: see text] higher than 70% and 90%. Under optimum conditions, the Yield[Formula: see text] andCPP[Formula: see text] of the AC-CoTAPc catalyst could be as high as 87.4% and 98.1%, with a purity[Formula: see text]of DMDS product of above 99.9%. AC-CoTAPc exhibits better catalytic and reuse performance than the commercial AC-supported sulphonated cobalt(II) phthalocyanine (AC-CoPcS) catalyst and shows broad industrial application prospects.

2018 ◽  
Vol 9 (1) ◽  
pp. 124 ◽  
Author(s):  
Zhiliang Cheng ◽  
Mingxing Dai ◽  
Xuejun Quan ◽  
Shuo Li ◽  
Daomin Zheng ◽  
...  

The Merox process was widely applied in the fine chemical industry to convert mercaptans into disulfides by oxidation with oxygen, including dimethyl disulfide (DMDS). In this paper, a new activated carbon (AC)-supported sulfonated cobalt phthalocyanine (AC-CoPcS) catalyst was prepared through the chemical linkage of ethylenediamine between them. UV−VIS, FT-IR, BET, and XPS were used to characterize the structure of the new catalyst. Then AC-CoPcS was applied to catalyze sodium methylmercaptide (SMM) oxidation for the preparation of DMDS. The effect of process parameters, such as reaction time, catalyst dosage, reaction temperature, and oxygen pressure on SMM conversion per pass (CPPSMM), yield (YieldDMDS), and purity of the DMDS (PurityDMDS) product were investigated to evaluate the catalytic performance of AC-CoPcS. The new supported catalyst exhibits better catalytic performance than the commercial one and can be properly reused four times to obtain CPPSMM and YieldDMDS higher than 90% and 70%. Under the optimum experimental conditions, the CPPSMM and YieldDMDS could reach as high as 98.7% and 86.8%, respectively, and the purity of the DMDS product is as high as 99.8%. This new supported catalyst exhibits good industrial application prospects.


2012 ◽  
Vol 531 ◽  
pp. 312-315 ◽  
Author(s):  
Ming Bo Xu ◽  
Jie Yang ◽  
Yong Kui Huang ◽  
Shui Jin Yang

A novel environmental friendly catalyst,H4SiW12O40/MCM-48, was prepared by impregnation method. The catalysts were characterized by means of XRD and FT-IR. The synthesis of butyraldehyde glycol acetal catalyzed by H4SiW12O40/MCM-48 was studied with butyraldehyde and glycol as reactants. H4SiW12O40/MCM-48 was an excellent catalyst for the synthesizing butyraldehyde glycol acetal and Keggin structure of H4SiW12O40 kept unchanged after being impregnated on surface of the molecular sieve support. Effects of n(butyraldehyde)∶n(glycol), catalyst dosage, cyclohexane(water-stripped reagent ) and reaction time on yields of the product were investigated. The optimum conditions had been found, that is, molar ratio of butyraldehyde to glycol is1:1.4,mass ratio of catalyst used to the reactants is 0.4% and reaction time is 45 min. Under these conditions, the yield of butyraldehyde glycol acetal can reach 73.3%.


2018 ◽  
Vol 78 (10) ◽  
pp. 2158-2170 ◽  
Author(s):  
Mohammad Malakootian ◽  
Alireza Nasiri ◽  
Hakimeh Mahdizadeh

Abstract Ciprofloxacin (CIP) is considered as a biological resistant pollutant. The CoFe2O4/activated carbon@chitosan (CoFe2O4/AC@Ch) prepared as a new magnetic nanobiocomposite and used for adsorption of CIP. CoFe2O4/AC@Ch was characterized by Fourier transform-infrared (FT-IR), field emission scanning electron microscope (FESEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), and Brunauer–Emmett–Teller (BET) surface area measurements. The pHZPC value of the nanobiocomposite was estimated to be 6.4 by solid addition method. The prepared magnetic nanobiocomposites can be separated easily from water by an external magnet and reused. The effect of CIP concentration (10–30 mg/L), adsorbent dosage (12–100 mg/L), contact time (5–30 min) and pH (3–11) as independent variables on ciprofloxacin removal efficiency was evaluated. Optimum conditions were obtained in CIP concentration: 10 mg/L, adsorbent dosage: 100 mg/L, contact time: 15 min and pH: 5. In this condition, maximum CIP removal was obtained as 93.5%. The kinetic and isotherm equations showed that the process of adsorption followed the pseudo-second order kinetic and Langmuir isotherm. The results indicate that the prepared magnetic nanobiocomposite can be used as good adsorbent for the removal of CIP from aqueous solution and can be also recycled.


Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 785
Author(s):  
Peirong Niu ◽  
Xiao Ren ◽  
Deyuan Xiong ◽  
Shilei Ding ◽  
Yuanlin Li ◽  
...  

In this study, silicoaluminophosphate (SAPO)-34 and Me (Me = Cr, Co)-modified SAPO-34 were synthesized and used as catalysts to investigate the catalytic performance by means of a probe reaction from ethanol to ethylene. The metal oxides were loaded on the SAPO-34 support via an impregnation method. The synthesized catalysts were characterized using XRD, SEM, EDX, FT-IR, NH3-TPD, BET, and TGA techniques. Compared to SAPO-34, SAPO-34 doped with metal oxides showed the same chabazite (CHA) topology. The structure and properties of the catalyst were further optimized by varying the amount of Me. The experimental results showed that Co-Cr/SAPO-34 exhibited the best catalytic performance when the reaction temperature reached 400 °C at a weight hourly space velocity (WHSV) of 3.5 h−1, for which the single-pass conversion of ethanol was determined as 99.15%, and the selectivity of ethylene was 99.4% at an optimum catalytic performance in the reaction of up to 600 min. In addition, Co-Cr/SAPO-34 exhibited better catalytic activity and anti-coking ability than pure SAPO-34, which was attributed to its enhanced pore structure and moderate acidity. It can also be concluded from the results of this experiment that the performance of the Co-Cr bimetal-supported catalyst is better than that of the Cr mono-metal catalyst.


2012 ◽  
Vol 550-553 ◽  
pp. 252-256 ◽  
Author(s):  
Li Yang ◽  
Heng Zhang ◽  
Rui Yi Yan ◽  
Xiang Ping Zhang ◽  
Guang Jin Zhang ◽  
...  

Keggin-type 12-phosphomolybdic acid with molybdenum partially substituted by vanadium and protons partially substituted by alkali and transition metals was synthesized for the selective oxidation of methacrolein to methacrylic acid. The structures of the catalysts were studied by FT-IR, XRD, TG-DTA and BET. The effects of the additive amount of PEG400, calcination temperature and the content of Cs on the catalytic performance were investigated. Results show that specific surface areas of the catalysts increase with the increase of PEG400 amount; PEG400 is removed at 250 °C and the primary structure of the catalysts is not changed with the addition of PEG400. The conversion and selectivity increase with the Cs content, and then decrease. The catalyst with the ratio of Cs+: heteropoly anion=1:1 exhibits good catalytic performance for the selective oxidation of MAL. Under the optimum conditions, the conversion of MAL and selectivity of MAA are 76.4% and 83.6% respectively.


2018 ◽  
Vol 7 (4.37) ◽  
pp. 127
Author(s):  
Muhanned Abdul-Redhah Aidan ◽  
Wafaa Mahdi Alkoofee ◽  
Ala`a A. Sultan ◽  
Wessal M. Khamis ◽  
Sinan Medhat

The polymers derived from heterocyclic rings like imidazole was prepared and supported to produce catalytic active supported catalyst. This catalyst was characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), H NMR and UV-visible spectroscopy. The catalyst showed high catalytic activity in the oxidation of cyclohexene and cyclopentene under optimized conditions. In this work cyclohexene and cyclopentene were selected as model alkene for determination the capacity of the prepared imidazole polymer catalyst under optimized conditions of temperature and time of reaction. The catalyst could be readily separated from the catalytic system using uploading 3-5 milligrams of Copper(II), Nickel(II) and Cobalte(II) ions with the surface of polymer the conversion them to nano-particle which are identified by x-ray diffraction. For this research, a statistical method called Response Surface Methodology (RSM) has been used to economize the number of experiments and their meaningful interpretation. The effect of metallated polymer with Copper(II), Nickel(II) and Cobalte(II) were taken to increase the efficiency of oxidation. Optimization results for 0.33 mmole cyclohexene and cyclopentene showed that maximum oxidation efficiency 90. % was achieved at the optimum conditions: catalyst amount 350 mg, temperature 70.0, time 3.30 h and oxidant= 5.25 m mole.   


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 105
Author(s):  
Tae Young Kim ◽  
Seong Bin Jo ◽  
Jin Hyeok Woo ◽  
Jong Heon Lee ◽  
Ragupathy Dhanusuraman ◽  
...  

Co–Fe–Al catalysts prepared using coprecipitation at laboratory scale were investigated and extended to pilot scale for high-calorific synthetic natural gas. The Co–Fe–Al catalysts with different metal loadings were analyzed using BET, XRD, H2-TPR, and FT-IR. An increase in the metal loading of the Co–Fe–Al catalysts showed low spinel phase ratio, leading to an improvement in reducibility. Among the catalysts, 40CFAl catalyst prepared at laboratory scale afforded the highest C2–C4 hydrocarbon time yield, and this catalyst was successfully reproduced at the pilot scale. The pelletized catalyst prepared at pilot scale showed high CO conversion (87.6%), high light hydrocarbon selectivity (CH4 59.3% and C2–C4 18.8%), and low byproduct amounts (C5+: 4.1% and CO2: 17.8%) under optimum conditions (space velocity: 4000 mL/g/h, 350 °C, and 20 bar).


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xiaoliang Liu ◽  
Jing Shi ◽  
Guang Yang ◽  
Jian Zhou ◽  
Chuanming Wang ◽  
...  

AbstractZeolite morphology is crucial in determining their catalytic activity, selectivity and stability, but quantitative descriptors of such a morphology effect are challenging to define. Here we introduce a descriptor that accounts for the morphology effect in the catalytic performances of H-ZSM-5 zeolite for C4 olefin catalytic cracking. A series of H-ZSM-5 zeolites with similar sheet-like morphology but different c-axis lengths were synthesized. We found that the catalytic activity and stability is improved in samples with longer c-axis. Combining time-resolved in-situ FT-IR spectroscopy with molecular dynamics simulations, we show that the difference in catalytic performance can be attributed to the anisotropy of the intracrystalline diffusive propensity of the olefins in different channels. Our descriptor offers mechanistic insight for the design of highly effective zeolite catalysts for olefin cracking.


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