Platinum-Tin Nano-Catalysts Supported on Alumina for Direct Dehydrogenation of n-Butane

2015 ◽  
Vol 15 (10) ◽  
pp. 8305-8310 ◽  
Author(s):  
Jong Kwon Lee ◽  
Hyun Seo ◽  
Ung Gi Hong ◽  
Gle Park ◽  
Yeonshick Yoo ◽  
...  
Keyword(s):  
Surface Area ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Hydrogen Chemisorption ◽  
Impregnation Method ◽  
Platinum Surface ◽  
Catalytic Activities ◽  
Nano Catalyst ◽  
Basic Solutions ◽  
Nano Catalysts

Al2O3 supports were prepared by a precipitation method using various basic solutions (NaOH, KOH, NH4OH, and Na2CO3) as precipitation agents, and Pt/Sn/Al2O3 nano-catalysts were then prepared by a sequential impregnation method. The prepared catalysts were applied to the direct dehydrogenation of n-butane to n-butenes and 1,3-butadiene. The effect of precipitation agents on the physicochemical properties and catalytic activities of Pt/Sn/Al2O3 nano-catalysts in the direct dehydrogenation of n-butane was investigated. Catalytic performance of Pt/Sn/Al2O3 nanocatalysts decreased in order of Pt/Sn/Al2O3 (NaOH) > Pt/Sn/Al2O3 (KOH) > Pt/Sn/Al2O3 (NH4OH) > Pt/Sn/Al2O3 (Na2CO3). Among the catalysts tested, Pt/Sn/Al2O3 (NaOH) nano-catalyst showed the best catalytic performance in terms of yield for total dehydrogenation products (TDP, n-butenes and 1,3-butadiene). Hydrogen chemisorption experiments revealed that platinum surface area of the catalyst was closely related to the catalytic performance. Yield for TDP increased with increasing platinum surface area of the catalyst.

Synthesis of Dimethyl Carbonate from Ethylene Carbonate and Methanol Over Nano-Catalysts Supported on CeO2–MgO

2015 ◽  
Vol 15 (10) ◽  
pp. 8330-8335 ◽  
Author(s):  
Jin Oh Jun ◽  
Joongwon Lee ◽  
Ki Hyuk Kang ◽  
In Kyu Song
Keyword(s):  
Dimethyl Carbonate ◽  
Ethylene Carbonate ◽  
Earth Metal ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Reaction Yield ◽  
Incipient Wetness Impregnation ◽  
Impregnation Method ◽  
Nano Catalyst ◽  
Nano Catalysts

A series of CeO2(X)–MgO(1−X) (X = 0, 0.25, 0.5, 0.75, and 1.0) nano-catalysts were prepared by a co-precipitation method for use in the synthesis of dimethyl carbonate from ethylene carbonate and methanol. Among the CeO2(X)–MgO(1−X) catalysts, CeO2(0.25)–MgO(0.75) nano-catalyst showed the best catalytic performance. Alkali and alkaline earth metal oxides (MO = Li2O, K2O, Cs2O, SrO, and BaO) were then supported on CeO2(0.25)–MgO(0.75) by an incipient wetness impregnation method with an aim of improving the catalytic performance of CeO2(0.25)–MgO(0.75). Basicity of the catalysts was determined by CO2-TPD experiments in order to elucidate the effect of basicity on the catalytic performance. The correlation between catalytic performance and basicity showed that basicity played an important role in the reaction. Yield for dimethyl carbonate increased with increasing basicity of the catalysts. Among the catalysts tested, Li2O/CeO2(0.25)–MgO(0.75) nano-catalyst with the largest basicity showed the best catalytic performance in the synthesis of dimethyl carbonate.

Direct Dehydrogenation of n-Butane Over Pt/Sn/Zn/γ-Al2O3 Nano-Catalyst: Effect of Zn Content

2015 ◽  
Vol 15 (10) ◽  
pp. 8318-8323
Author(s):  
Hyun Seo ◽  
Jong Kwon Lee ◽  
Ung Gi Hong ◽  
Gle Park ◽  
Yeonshick Yoo ◽  
...  
Keyword(s):  
Surface Area ◽  
Zinc Content ◽  
Catalytic Performance ◽  
Impregnation Method ◽  
Support Interaction ◽  
Nano Catalyst ◽  
Metal Support Interaction ◽  
Zn Content ◽  
Metal Support ◽  
Nano Catalysts

A series of Pt/Sn/XZn/γ-Al2O3 nano-catalysts with different Zn content (X = 0, 0.25, 0.5, 0.75, and 1.0 wt%) were prepared by a sequential impregnation method. They were applied to the direct dehydrogenation of n-butane to n-butene and 1,3-butadiene. The effect of zinc content of Pt/Sn/XZn/γ-Al2O3 nano-catalysts on their physicochemical properties and catalytic activities in the direct dehydrogenation of n-butane was investigated. The catalytic performance of Pt/Sn/XZn/γ-Al2O3 nano-catalysts strongly depended on zinc content. Among the catalysts tested, Pt/Sn/0.5Zn/γ-Al2O3 nano-catalyst showed the best catalytic performance in terms of yield for total dehydrogenation products (TDP, n-butene and 1,3-butadiene). TPR (temperature-programmed reduction) and H2-chemisorption experiments were carried out to measure metal-support interaction and Pt surface area of the catalysts. Experimental results revealed that metal-support interaction and Pt surface area of the catalysts were closely related to the catalytic performance. Yield for TDP increased with increasing metal-support interaction and Pt surface area of the catalysts.

Magnetic Spinel Ferrite: An Efficient, Reusable Nano Catalyst for HMFSynthesis

2021 ◽  
Vol 10 ◽  
Author(s):  
Jyoti Dhariwal ◽  
Ravina Yadav ◽  
Sheetal Yadav ◽  
Anshu Kumar Sinha ◽  
Chandra Mohan Srivastava ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
Heterogeneous Catalysts ◽  
Spinel Ferrite ◽  
Active Surface ◽  
Catalytic Performance ◽  
Ferrite Nanoparticles ◽  
Precipitation Method ◽  
Magnetic Characteristics ◽  
Nano Catalyst

Aim: In the present work, the preparation and catalytic activity of spinel ferrite [MFe2O4; M = Fe, Mn, Co, Cu, Ni] nanoparticles to synthesize 5-hydroxymethylfurfural (HMF) have been discussed. Background: Ferrites possess unique physicochemical properties, including excellent magnetic characteristics, high specific surface area, active surface sites, high chemical stability, tunable shape and size, and easy functionalization. These properties make them essential heterogeneous catalysts in many organic reactions. Objective: This study aims to synthesize a series of transition metal ferrite nanoparticles and use them in the dehydration of carbohydrates for 5-hydroxymethylfurfural (HMF) synthesis. Method: The ferrite nanoparticles were prepared via the co-precipitation method, and PXRD confirmed their phase stability. The surface area and the crystallite size of the nanoparticles were calculated using BET and PXRD, respectively. Result: The easily prepared heterogeneous nanocatalyst showed a significant catalytic performance, and among all spinel ferrites, CuFe2O4 revealed maximum catalytic ability. Conclusion: Being a heterogeneous catalyst and magnetic in nature, ferrite nanoparticles were easily recovered by using an external magnet and reused up to several runs without substantial loss in catalytic activity. Others: HMF was synthesized from fructose in a good yield of 71%.

Dehydration of Glycerin to Acrolein Over Heteropolyacid Nano-Catalysts Supported on Silica–Alumina

2015 ◽  
Vol 15 (10) ◽  
pp. 8324-8329 ◽  
Author(s):  
Tae Hun Kang ◽  
Jung Ho Choi ◽  
Jun Seon Choi ◽  
In Kyu Song
Keyword(s):  
Physicochemical Properties ◽  
Surface Area ◽  
Pore Volume ◽  
Catalytic Performance ◽  
Brønsted Acidity ◽  
Catalytic Activities ◽  
Brönsted Acidity ◽  
Silica Alumina ◽  
Nano Catalysts

A series of H3PW12O40 nano-catalysts supported on silica–alumina (XH3PW12O40/SA (X = 10, 15, 20, 25, and 30)) with different H3PW12O40 content (X, wt%) were prepared, and they were applied to the dehydration of glycerin to acrolein. The effect of H3PW12O40 content on the physicochemical properties and catalytic activities of XH3PW12O40/SA nano-catalysts was investigated. Surface area and pore volume of XH3PW12O40/SA catalysts decreased with increasing H3PW12O40 content. Formation of H3PW12O40 aggregates was observed in the catalysts with high H3PW12O40 loading. Brønsted acidity of the catalysts showed a volcano-shaped trend with respect to H3PW12O40 content. It was revealed that yield for acrolein increased with increasing Brønsted acidity of XH3PW12O40/SA catalysts. Brønsted acidity of XH3PW12O40/SA catalysts served as a crucial factor determining the catalytic performance in the dehydration of glycerin. Among the catalysts tested, 25H3PW12O40/SA catalyst with the largest Brønsted acidity showed the best catalytic performance.

Study on Alkylation of Catechol with Ethanol by Al-P-Ti-O Oxides

2012 ◽  
Vol 599 ◽  
pp. 114-117 ◽  
Author(s):  
Xiao Mei Zhu ◽  
Bing Sun ◽  
Cheng Huo
Keyword(s):  
Citric Acid ◽  
Surface Area ◽  
Vapour Phase ◽  
Cane Sugar ◽  
Precipitation Method ◽  
Title Reaction ◽  
Catalytic Activities ◽  
P Content ◽  
The Stability ◽  
Ti Content

Vapour-phase alkylation of catechol with ethanol has been investigated over Al-P-Ti-O oxides prepared by non-uniform precipitation method. The catalytic activities decrease with the increase of P content. The catalytic activities increase with increasing Ti content, while the selectivity to guathol decreases. The results of XRD characterization demonstrate that the increase of titanium and the addition of additive affects the structure of the catalysts. The addition of additive (cane sugar or citric acid) decrease the catalytic activities of the catalysts, while increase the stability of the catalyst. Both the conversion of catechol and the selectivity to guathol decrease by the addition of additive, and the C-alkylation products increase obviously. The results indicate that the appropriate pores and surface area are enough for the title reaction, lager pore and higher surface area are favorable to C-alkylation products and stability of catalyst.

STUDY ON NANO COPPER-BASED CATALYSTS FOR THE HYDROGENATION OF METHYL 3-HYDROXYPROPIONATE TO 1, 3-PROPANEDIOL

2009 ◽  
Vol 16 (03) ◽  
pp. 343-349 ◽  
Author(s):  
YUZHOU YING ◽  
KANKA FENG ◽  
ZHIGUO LV ◽  
ZHENMEI GUO ◽  
JINSHENG GAO
Keyword(s):  
Fixed Bed ◽  
Side Reaction ◽  
Catalytic Performance ◽  
Fixed Bed Reactor ◽  
Precipitation Method ◽  
Active Components ◽  
Analysis Technique ◽  
Co Precipitation ◽  
Nano Catalysts ◽  
Adsorption Desorption

Nano copper-based catalysts were prepared by co-precipitation method and the performance of catalytic hydrogenation for methyl 3-hydroxypropionate (MHP) to 1, 3-propanediol (1, 3-PDO) on the nano catalysts were studied under a high-pressure microcontinuum fixed-bed reactor. The effects of structure, texture, and composition of the catalysts on the catalytic performance were investigated by characterizing the catalysts with XRD, TG–DTG, SEM, and N 2 adsorption/desorption analysis technique. The results showed that addition of promoters enhanced the activity and selectivity of copper-based catalysts, which promoted the dispersion of the active components effectively and stabilized the active center of the catalysts. Especially, the copper-based catalyst of loaded P could restrain side-reaction effectively and improve selectivity obviously, the conversion of MHP and the selectivity of 1, 3-PDO could be 91.30% and reach 90.15%, respectively.

Study on the Cu-Ni/Y2O3-ZrO2 Catalytic Performance in Ethanol Steam Reforming

2012 ◽  
Vol 512-515 ◽  
pp. 2257-2261 ◽  
Author(s):  
Hong Da Wu ◽  
Ying Gui Jia ◽  
Yu Yin ◽  
Lue Zhao
Keyword(s):  
Steam Reforming ◽  
Conversion Rate ◽  
Carbon Deposition ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Ethanol Conversion ◽  
Ethanol Steam Reforming ◽  
Impregnation Method ◽  
Catalyst Composition ◽  
Ethanol Steam

Y2O3-ZrO2 support was prepared by two-step precipitation method with ammonia and oxalic acid. A series of Cu-Ni/Y2O3-ZrO2 catalysts were prepared by impregnation method. The catalysts were investigated and then characterized by XRD and SEM results. The activity of catalysts in ethanol steam reforming was studied. The effects of the catalyst composition on the ethanol conversion rate were discussed and the catalysts inactivation phenomenon under the temperature ranging from 673K to 723K was then analyzed. The results show that 1Cu9Ni/1Y9Zr catalyst has higher activity in ethanol steam reforming, over which ethanol conversion rate is higher than 98% under the situation of 623K, while the inactivation of catalysts with Cu/Ni>3/7 at 673K~723K was caused by carbon deposition .

scholarly journals Properties and catalytic performance of sulphate-vanadia impregnated fumed silica as oxidative catalyst

2015 ◽  
Vol 11 (2) ◽  
Author(s):  
Nor Masdiana Zulkeple ◽  
Norhasyimah Mohd Kamal ◽  
Jamilah Mohd Ekhsan ◽  
Salasiah Che Me ◽  
Swee Ean Lim ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Catalytic Activity ◽  
Charge Transfer ◽  
Surface Area ◽  
Sulphuric Acid ◽  
Fumed Silica ◽  
Catalytic Performance ◽  
Support Surface ◽  
High Catalytic Activity ◽  
Impregnation Method

A series of sulphate-vanadia impregnated fumed silica oxidative catalysts were synthesized via impregnation method. The samples were prepared by impregnation of 1 wt% of vanadium and 0.2 M of sulphuric acid onto fumed silica as support. Surface area of the silica supported samples were similar of 118 m2/g. UV-Vis DRS results showed existence of o supported V species and the charge transfer bands associated with O2- to V5+ in tetrahedral environments. Catalytic performance were evaluated via epoxidation of 1-octene to 1,2-epoxyoctane using hydrogen peroxide as an oxidant. It had been demonstrated that sulphate-vanadia impregnated fumed silica had high catalytic activity of 626 ± 0.2 mmol epoxide was produced after 24 h reaction. This may indicate that more oxidative sites were generated after the impregnation of V and sulphate onto the SiO2 matrixes.

scholarly journals Removal efficiency and mechanism of bio-treated coking wastewater by catalytic ozonation using MnO2 modified with anionic precursors

2020 ◽  
Vol 26 (5) ◽  
pp. 200394-0
Author(s):  
Jie Zhang ◽  
Ben Dong ◽  
Ding Ding ◽  
Shilong He ◽  
Sijie Ge
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Catalytic Performance ◽  
Catalytic Ozonation ◽  
Relative Content ◽  
Precipitation Method ◽  
Coking Wastewater ◽  
Physiochemical Properties ◽  
Removal Efficiencies

In this paper, MnO<sub>2</sub> catalyst were firstly prepared and modified by four kinds of anionic precursors (i.e., NO<sub>3</sub><sup>-</sup>, AC<sup>-</sup>, SO<sub>4</sub><sup>2-</sup> and Cl<sup>-</sup>) through redox precipitation method. After that, bio-treated coking wastewater (BTCW) was prepared and employed as targeted pollutants to investigate the catalytic ozonation performance of prepared-MnO<sub>2</sub> catalyst was investigated and characterized by the removal efficiencies and mechanism of the prepared bio-treated coking wastewater (BTCW), which was employed as the targeted pollutants. Specifically, the effects of specific surface area, crystal structure, valence state of Mn element and lattice oxygen content on catalytic activity of MnO<sub>2</sub> materials were characterized by BET, XRD and XPS, respectively. Results showed that COD of BTCW could be removed 47.39% under MnO<sub>2</sub>-NO<sub>3</sub><sup>-</sup> catalyst with 2 h reaction time, which was much higher than that of MnO<sub>2</sub>-AC<sup>-</sup> (3.94%), MnO<sub>2</sub>-SO<sub>4</sub><sup>2-</sup> (12.42%), MnO<sub>2</sub>-Cl<sup>-</sup> (12.94%) and pure O<sub>3</sub> without catalyst (21.51%), respectively. So, MnO<sub>2</sub>-NO<sub>3</sub><sup>-</sup> presented the highest catalytic performance among these catalysts. The reason may be attributed to a series of better physiochemical properties including the smaller average grain, the larger specific surface area and active groups, more crystal defect and oxygen vacancy, higher relative content of Mn<sup>3+</sup> and adsorbed oxygen (O<sub>ads</sub>) than that of another three catalysts.

scholarly journals Oxidation of soot over supported RuRe nanoparticles prepared by the microwave-polyol method

2021 ◽  
Author(s):  
Katarzyna Adamska ◽  
Szymon Smykała ◽  
Sebastian Zieliński ◽  
Damian Szymański ◽  
Agnieszka Hojeńska ◽  
...  
Keyword(s):  
Bimetallic Nanoparticles ◽  
Catalytic Properties ◽  
Soot Oxidation ◽  
Catalytic Performance ◽  
Polyol Method ◽  
Nano Catalyst ◽  
The Stability ◽  
Nano Catalysts ◽  
The Relationship ◽  
Very High

AbstractThe oxidation of soot over RuRe bimetallic nanoparticles (NPs) supported on γ-Al2O3 has been investigated. The catalysts were synthesized by a microwave-polyol method and characterized by ICP, BET, TEM, STEM-EDS, XRD and XPS techniques. The study revealed that the proper choice of the Re loading (0.4–2.0 wt%) is crucial for the catalytic behavior of the 2% Ru–Re/Al2O3 nano-catalysts.The best catalytic properties, in terms of overall activity and stability, were observed for the 2%Ru-0.8%Re/γ-Al2O3 nano-catalyst. The stability of all bimetallic 2% Ru–Re nano-catalysts in catalytic soot oxidation in the presence of oxygen is very high in contrast to the 2% Ru/γ-Al2O3 sample. The presence of rhenium in the catalytic system hinder the formation of large RuO2 agglomerates leading to a better dispersion of active ruthenium phase and a better catalytic performance. The relationship between the catalytic activity of Ru–Re/γ-Al2O3 and the synergetic roles of Ru and Re is discussed.

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