scholarly journals Synthesis and Catalytic Activity of Activated Carbon Supported Sulfonated Cobalt Phthalocyanine in the Preparation of Dimethyl Disulfide

2018 ◽  
Vol 9 (1) ◽  
pp. 124 ◽  
Author(s):  
Zhiliang Cheng ◽  
Mingxing Dai ◽  
Xuejun Quan ◽  
Shuo Li ◽  
Daomin Zheng ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Supported Catalyst ◽  
Dimethyl Disulfide ◽  
Catalytic Performance ◽  
Cobalt Phthalocyanine ◽  
Experimental Conditions ◽  
Ft Ir ◽  
Catalyst Dosage ◽  
Chemical Linkage ◽  
Application Prospects

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.

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 ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Supported Catalyst ◽  
Dimethyl Disulfide ◽  
Catalytic Performance ◽  
Optimum Conditions ◽  
Chemical Grafting ◽  
Ft Ir ◽  
Catalyst Dosage ◽  
Yield Formula ◽  
Application Prospects

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.

Catalytic Wet Oxidating Fulvic Acid By Zero-Valent Copper Chitosan Activated Carbon Ball: Plackett-Buiman Design and Response Surface Modeling Optimization

2021 ◽  
Author(s):  
Chaofei Song ◽  
Yue Lv ◽  
Xia Qin ◽  
Jiaxin Cui ◽  
Chengrui Guo ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Fulvic Acid ◽  
Response Surface ◽  
Removal Rate ◽  
Catalytic Performance ◽  
High Catalytic Activity ◽  
Catalytic Wet Oxidation ◽  
Experimental Conditions ◽  
Statistical Tool ◽  
Average Maximum

Abstract In this paper, the active component zero-valent copper (ZVC) supported by chitosan activated carbon ball (CTS-ACB) (i.e. ZVC/CTS-ACS catalyst) was successfully prepared. The characterization results showed obvious characteristics of activated carbon and zero-valent copper. The catalyst was used to degrade fulvic acid (FA) in catalytic wet oxidation(CWO) system. The two significant factors acidity and temperature were found with the statistical tool Plackett-Buimanhe(PB) in CWO for FA removal. Then the response surface methodology(RSM) model was used to optimize the experimental conditions in order to obtain the optimal FA removal rate. With the optimal experimental parameters, that is, a temperature of 94°C and an acidity of 3.8, the average maximum removal rate of FA was 93.02%, which was in agreement with the expected result of the model 93.86%, indicating that the model is well established. The comparison of catalytic performance showed that the addition of catalyst ZVC / CTS-ACS could increase the removal rate of FA, colour number(CN) and TOC by 93.6%, 83.5% and 81.9% respectively. The utilization of ZVC can greatly increase the mineralization rate of FA , which indicates the high catalytic activity and minerazation of the catalyst.

scholarly journals Anthocyanin-Sensitized TiO2 Nanoparticles for Phenazopyridine Photodegradation under Solar Simulated Light

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Ahed H. Zyoud ◽  
Fedaa Saleh ◽  
Muath H. Helal ◽  
Ramzi Shawahna ◽  
Hikmat S. Hilal
Keyword(s):  
Activated Carbon ◽  
Organic Contaminants ◽  
Carbon Particle ◽  
Supported Catalyst ◽  
Wide Band ◽  
Natural Dye ◽  
Contaminant Removal ◽  
Experimental Conditions ◽  
Water Contaminants ◽  
Economic Methods

Pharmaceutical wastes are emerging as water contaminants. Like other organic contaminants, it is necessary to find safe and economic methods to remove them from the water. In this work, anthocyanin was used as a natural dye sensitizer for the wide band gap nanosize rutile TiO2. The TiO2/Anthocyanin particles were supported on activated carbon particle surfaces. The resulting composite, which was prepared and characterized by different methods, was then used as a catalyst in the photodegradation of phenazopyridine (a model pharmaceutical contaminant) under a solar simulated light. Depending on experimental conditions, up to 90% of the contaminant was mineralized leaving no new organic products in the reaction mixture. The results show the feasibility of using the activated carbon-supported TiO2/Anthocyanin photocatalyst for pharmaceutical contaminant removal in water. The natural dye anthocyanin readily sensitized the TiO2 to visible light. The unsupported TiO2, with its nanosize particles, was not easy to recover by simple separation methods, while the activated carbon-supported catalyst was easily isolated by decantation after reaction cessation. Moreover, the recovered AC/TiO2 catalyst could also be regenerated by adding fresh anthocyanin sensitizer after recovery for further reuse. Keeping the contaminant molecules closer to the catalytic sites by adsorption, the support also enhanced the efficiency of photocatalyst.

scholarly journals Synthesis of Highly Selective and Stable Co-Cr/SAPO-34 Catalyst for the Catalytic Dehydration of Ethanol to Ethylene

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 785
Author(s):  
Peirong Niu ◽  
Xiao Ren ◽  
Deyuan Xiong ◽  
Shilei Ding ◽  
Yuanlin Li ◽  
...  
Keyword(s):  
Metal Oxides ◽  
Supported Catalyst ◽  
Space Velocity ◽  
Catalytic Performance ◽  
Metal Catalyst ◽  
Impregnation Method ◽  
Structure And Properties ◽  
Weight Hourly Space Velocity ◽  
Ft Ir ◽  
Better Than

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.

scholarly journals A diffusion anisotropy descriptor links morphology effects of H-ZSM-5 zeolites to their catalytic cracking performance

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xiaoliang Liu ◽  
Jing Shi ◽  
Guang Yang ◽  
Jian Zhou ◽  
Chuanming Wang ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Catalytic Cracking ◽  
Catalytic Performance ◽  
Zeolite Catalysts ◽  
Time Resolved ◽  
Cracking Performance ◽  
Morphology Effect ◽  
Ft Ir ◽  
The Difference ◽  
Dynamics Simulations

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.

scholarly journals Study on Chromaticity Removal from Mineral Processing Wastewater with Salicylic Hydroxamic Acid by Granular Activated Carbon Catalyzed Ozonation

Minerals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 359
Author(s):  
Liping Zhang ◽  
Shengnian Wu ◽  
Nan Zhang ◽  
Ruihan Yao ◽  
Eryong Wu
Keyword(s):  
Activated Carbon ◽  
Reaction Time ◽  
Hydroxamic Acid ◽  
Ph Value ◽  
Oxygen Demand ◽  
Granular Activated Carbon ◽  
Mineral Processing ◽  
Ultraviolet Absorption Spectrum ◽  
Experimental Conditions ◽  
Removal Ratio

Salicylic hydroxamic acid is a novel flotation reagent used in mineral processing. However, it impacts the flotation wastewater leaving behind high chromaticity which limits its reuse and affects discharge for mining enterprises. This study researched ozonation catalyzed by the granular activated carbon (GAC) method to treat the chromaticity of the simulated mineral processing wastewater with salicylic hydroxamic acid. The effects of pH value, ozone (O3) concentration, GAC dosage, and reaction time on chromaticity and chemical oxygen demand (CODCr) removal were discussed. The results of individual ozonation experiments showed that the chromaticity removal ratio reached 79% and the effluent chromaticity exceeded the requirement of reuse and discharge when the optimal experimental conditions were pH value 3, ozone concentration 6 mg/L, and reaction time 40 min. The orthogonal experimental results of catalytic ozonation with GAC on chromaticity removal explained that the chromaticity removal ratio could reach 96.36% and the chromaticity of effluent was only 20 when the optimal level of experimental parameters was pH value 2.87, O3 concentration 6 mg/L, GAC dosage 0.06 g/L, reaction time 60 min respectively. The degradation pathway of salicylic hydroxamic acid by ozonation was also considered based on an analysis with ultraviolet absorption spectrum and high-performance liquid chromatography (HPLC).

scholarly journals Novel Preparation of Cu and Fe Zirconia Supported Catalysts for Selective Catalytic Reduction of NO with NH3

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 55
Author(s):  
Katarzyna Świrk ◽  
Ye Wang ◽  
Changwei Hu ◽  
Li Li ◽  
Patrick Da Costa ◽  
...  
Keyword(s):  
Selective Catalytic Reduction ◽  
Catalytic Reduction ◽  
Supported Catalysts ◽  
Catalytic Performance ◽  
Experimental Conditions ◽  
One Pot ◽  
Nh3 Scr ◽  
Scr Of No ◽  
Temperature Programmed ◽  
Stationary Sources

Copper and iron promoted ZrO2 catalysts were prepared by one-pot synthesis using urea. The studied catalysts were characterized by XRD, N2 physisorption, XPS, temperature-programmed desorption of NH3 (NH3-TPD), and tested by the selective catalytic reduction by ammonia (NH3-SCR) of NO in the absence and presence of water vapor, under the experimental conditions representative of exhaust gases from stationary sources. The influence of SO2 on catalytic performance was also investigated. Among the studied catalysts, the Fe-Zr sample showed the most promising results in NH3-SCR, being active and highly selective to N2. The addition of SO2 markedly improved NO and NH3 conversions during NH3-SCR in the presence of H2O. The improvement in acidic surface properties is believed to be the cause.

scholarly journals Degradation of hydroxypropyl guar gum at wide pH range by a heterogeneous Fenton-like process using bentonite-supported Cu(0)

2020 ◽  
Vol 82 (8) ◽  
pp. 1635-1642
Author(s):  
Ling Zhou ◽  
Zhongying Xu ◽  
Jie Zhang ◽  
Zhifang Zhang ◽  
Ying Tang
Keyword(s):  
Active Sites ◽  
Guar Gum ◽  
Heterogeneous Reaction ◽  
Removal Rate ◽  
Catalytic Performance ◽  
High Dispersion ◽  
Application Process ◽  
Experimental Conditions ◽  
Hydroxypropyl Guar ◽  
Hydroxypropyl Guar Gum

Abstract To seek for efficient Fenton-like oxidation processing for treatment of waste fracturing fluid containing hydroxypropyl guar gum (HPGG), in heterogeneous reaction, five bentonite-supported zero-valent metal catalysts were prepared by liquid-phase reduction. The results showed that the bentonite-supported zero-valent copper exhibited best catalytic performance, attributed to the high dispersion of active sites of zero-valent copper. The effects of the most relevant operating factors (H2O2 concentration, catalyst dosage, temperature and pH) were evaluated in detail. Moreover, the chemical oxygen demand removal rate of HPGG can achieve 76% when the reaction time was selected at 45 min under optimal experimental conditions. The stability evaluation showed that the catalytic performance was almost unaffected after the catalyst was recycled and used once more showing the good stability of the bentonite-supported zero-valent copper in the application process.

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