Biomass Nanoporous Carbon-Supported Pd Catalysts for Partial Hydrogenation of Biodiesel: Effects of Surface Chemistry on Pd Particle Size and Catalytic Performance

Two types of cattail flower-derived nanoporous carbon (NPC), i.e., NPC activated with KOH and H3PO4, were produced and characterized using several techniques (e.g., Raman spectroscopy, nitrogen adsorption, and X-ray photoelectron spectroscopy). The influence of the carbon support characteristics on the particle sizes and chemical states of Pd in the synthesized Pd/NPC catalysts, which affect the catalytic activity and product selectivity, was analyzed. The surface chemistry properties of NPC were the main factors influencing the Pd particle size; by contrast, the textural properties did not significantly affect the size of the Pd particles on NPC supports. The use of Pd nanoparticles supported on the rich-functionalized surface carbons obtained by H3PO4 activation led to superior catalytic activity for the polyunsaturated fatty acid methyl ester (poly-FAME) hydrogenation, which could achieve 90% poly-FAME conversion and 84% selectivity towards monounsaturated FAME after a 45-min reaction time. This is due to the small Pd nanoparticle size and the high acidity of the catalysts, which are beneficial for the partial hydrogenation of poly-FAME in biodiesel. Conversely, the Pd nanoparticles supported on the high-surface-area carbon by KOH activation, with large Pd particle size and low acidity, required a longer reaction time to reach similar conversion and product selectivity levels.

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Ultrafinely dispersed Pd nanoparticles on a CN@MgO hybrid as a bifunctional catalyst for upgrading bioderived compounds

Green Chemistry ◽

10.1039/c4gc00850b ◽

2014 ◽

Vol 16 (9) ◽

pp. 4371-4377 ◽

Cited By ~ 28

Author(s):

Mingming Li ◽

Xuan Xu ◽

Yutong Gong ◽

Zhongzhe Wei ◽

Zhaoyin Hou ◽

...

Keyword(s):

Catalytic Activity ◽

Pd Nanoparticles ◽

Bifunctional Catalyst ◽

Tandem Reaction ◽

Product Selectivity ◽

Good Product ◽

Full Conversion

A bifunctional catalyst Pd/CN@MgO showed excellent catalytic activity in the above tandem reaction, achieving full conversion and good product selectivity.

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Transformation of methanol to hydrocarbons over Y zeolites with varying Si/Al ratio

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19871701 ◽

1987 ◽

Vol 52 (7) ◽

pp. 1701-1707 ◽

Cited By ~ 1

Author(s):

Miloslav Křivánek ◽

Nguyen Thiet Dung ◽

Pavel Jírů

Keyword(s):

Catalytic Activity ◽

Reaction Time ◽

Coke Formation ◽

Aliphatic Hydrocarbons ◽

Y Zeolite ◽

Y Zeolites ◽

Methanol To Hydrocarbons

The catalytic activity of Na, H-Y zeolite samples with a varying Si/Al ratio (2·5 to 20) in the transformation of methanol was determined. The amounts of formed individual aliphatic hydrocarbons as function of reaction time were correlated with the amount of Bronsted and Lewis centres on the catalysts. The effect of coke formation on the over-all course of the reaction has been demonstrated.

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Synthesis of tetrazolo[1,5-a]pyrimidine-6-carbonitriles using HMTA-BAIL@MIL-101(Cr) as a superior heterogeneous catalyst

Scientific Reports ◽

10.1038/s41598-021-84379-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mohammad Hossein Abdollahi-Basir ◽

Boshra Mirhosseini-Eshkevari ◽

Farzad Zamani ◽

Mohammad Ali Ghasemzadeh

Keyword(s):

Ionic Liquid ◽

Catalytic Activity ◽

Reaction Time ◽

Metal Organic Framework ◽

One Pot ◽

Short Reaction Time ◽

Three Component Reaction ◽

Metal Organic ◽

Ft Ir ◽

Novel Catalyst

AbstractA one-pot three component reaction of benzaldehydes, 1H-tetrazole-5-amine, and 3-cyanoacetyl indole in the presence of a new hexamethylenetetramine-based ionic liquid/MIL-101(Cr) metal–organic framework as a recyclable catalyst was explored. This novel catalyst, which was fully characterized by XRD, FE-SEM, EDX, FT-IR, TGA, BET, and TEM exhibited outstanding catalytic activity for the preparation of a range of pharmaceutically important tetrazolo[1,5-a]pyrimidine-6-carbonitriles with good to excellent yields in short reaction time.

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Low-temperature and atmospheric pressure plasma for palm biodiesel hydrogenation

Scientific Reports ◽

10.1038/s41598-021-92714-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Grittima Kongprawes ◽

Doonyapong Wongsawaeng ◽

Kanokwan Ngaosuwan ◽

Worapon Kiatkittipong ◽

Suttichai Assabumrungrat

Keyword(s):

Fatty Acid ◽

Cloud Point ◽

Atmospheric Pressure ◽

Oxidation Stability ◽

Acid Methyl Ester ◽

Energy Utilization ◽

Superior Performance ◽

Partial Hydrogenation ◽

Dbd Plasma ◽

Plasma Hydrogenation

AbstractPartially hydrogenated fatty acid methyl ester (H-FAME) is conventionally produced through partial hydrogenation under high pressure and elevated temperature in the presence of a catalyst. Herein, a novel green, catalyst-free, non-thermal and atmospheric pressure dielectric barrier discharge (DBD) plasma was employed instead of a conventional method to hydrogenate palm FAME. H-FAME became more saturated with the conversion of C18:2 and C18:3 of 47.4 and 100%, respectively, at 100 W input power, 1 mm gas-filled gap size and 80% H2 in the mixed gas at room temperature for 5 h, causing a reduction of the iodine value from 50.2 to 43.5. Oxidation stability increased from 12.8 to 20 h while a cloud point changed from 13.5 to 16 °C. Interestingly, DBD plasma hydrogenation resulted in no trans-fatty acid formation which provided a positive effect on the cloud point. This green DBD plasma system showed a superior performance to a conventional catalytic reaction. It is an alternative method that is safe from explosion due to the mild operating condition, as well as being highly environmentally friendly by reducing waste and energy utilization from the regeneration process required for a catalytic process. This novel green plasma hydrogenation technique could also be applied to other liquid-based processes.

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Feasibility of fly ash as fluxing agent in mid- and low-grade phosphate rock carbothermal reduction and its reaction kinetics

Green Processing and Synthesis ◽

10.1515/gps-2021-0008 ◽

2021 ◽

Vol 10 (1) ◽

pp. 157-168

Author(s):

Biwei Luo ◽

Pengfei Li ◽

Yan Li ◽

Jun Ji ◽

Dongsheng He ◽

...

Keyword(s):

Particle Size ◽

Fly Ash ◽

Reaction Time ◽

Carbothermal Reduction ◽

Industrial Waste ◽

Phosphate Rock ◽

Molar Ratio ◽

Low Grade ◽

Carbon Excess ◽

Fluxing Agent

Abstract The feasibility of industrial waste fly ash as an alternative fluxing agent for silica in carbothermal reduction of medium-low-grade phosphate ore was studied in this paper. With a series of single-factor experiments, the reduction rate of phosphate rock under different reaction temperature, reaction time, particle size, carbon excess coefficient, and silicon–calcium molar ratio was investigated with silica and fly ash as fluxing agents. Higher reduction rates were obtained with fly ash fluxing instead of silica. The optimal conditions were derived as: reaction temperature 1,300°C, reaction time 75 min, particle size 48–75 µm, carbon excess coefficient 1.2, and silicon–calcium molar ratio 1.2. The optimized process condition was verified with other two different phosphate rocks and it was proved universally. The apparent kinetics analyses demonstrated that the activation energy of fly ash fluxing is reduced by 31.57 kJ/mol as compared with that of silica. The mechanism of better fluxing effect by fly ash may be ascribed to the fact that the products formed within fly ash increase the amount of liquid phase in the reaction system and promote reduction reaction. Preliminary feasibility about the recycling of industrial waste fly ash in thermal phosphoric acid industry was elucidated in the paper.

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Monodisperse-porous cerium oxide microspheres as a new support with appreciable catalytic activity for a composite catalyst in benzyl alcohol oxidation

New Journal of Chemistry ◽

10.1039/d0nj05367h ◽

2021 ◽

Author(s):

Kadriye Özlem Hamaloğlu ◽

Rukiye Babacan Tosun ◽

Serap Ulu ◽

Hakan Kayi ◽

Cengiz Kavaklı ◽

...

Keyword(s):

Catalytic Activity ◽

Benzyl Alcohol ◽

Cerium Oxide ◽

Sol Gel ◽

Alcohol Oxidation ◽

Pd Nanoparticles ◽

Composite Catalyst ◽

Benzyl Alcohol Oxidation ◽

Supported Pd

A synergistic catalyst in the form of monodisperse-porous CeO2 microspheres supported Pd nanoparticles (Pd NPs) was synthesized. CeO2 microspheres 4 μm in size were obtained by a newly developed “sol-gel...

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Highly Dispersed Pd Species Supported on CeO2 Catalyst for Lean Methane Combustion: The Effect of the Occurrence State of Surface Pd Species on the Catalytic Activity

Catalysts ◽

10.3390/catal11070772 ◽

2021 ◽

Vol 11 (7) ◽

pp. 772

Author(s):

Yanxiong Liu ◽

Changhua Hu ◽

Longchun Bian

Keyword(s):

Catalytic Activity ◽

Oxygen Vacancies ◽

Methane Combustion ◽

Pd Nanoparticles ◽

High Concentration ◽

Ch4 Combustion ◽

Highly Active ◽

Δ Phase ◽

Occurrence State ◽

Comprehensive Characterization

The correlation between the occurrence state of surface Pd species of Pd/CeO2 for lean CH4 combustion is investigated. Herein, by using a reduction-deposition method, we have synthesized a highly active 0.5% PdO/CeO2-RE catalyst, in which the Pd nanoparticles are evenly dispersed on the CeO2 nanorods CeO2-R. Based on comprehensive characterization, we have revealed that the uniformly dispersed Pd nanoparticles with a particle size distribution of 2.3 ± 0.6 nm are responsible for the generation of PdO and PdxCe1−xO2−δ phase with –Pd2+–O2−–Ce4+– linkage, which can easily provide oxygen vacancies and facilitate the transfer of reactive oxygen species between the CeO2-R and Pd species. As a consequence, the remarkable catalytic activity of 0.5% Pd/CeO2-RE is related to the high concentration of PdO species on the surface of the catalyst and the synergistic interaction between the Pd species and the CeO2 nanorod.

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