Heterogeneous palladium catalysts in the hydrogenation of the carbon-carbon double bond

: The results of studies over the past ten years in the field of C=C bond hydrogenation in the presence of palladium catalysts deposited on various inorganic and organic carriers such activated carbons, carbon nanotubes, alumina, zeolites, or composite materials based on Al2O3-SiO2, polystyrene, polypropyleneimine, polyamidoamine and hybrid inorganic/polymer carriers are presented. The selectivity and rates of the hydrogenation process are considered and some comparisons are made. Porous supports and containing dendrimers generally retain palladium particles more effectively. Nanosized palladium stabilized by different dendrimers catalyzes the hydrogenation of C=C bonds in polyfunctional compounds chemoselectively without affecting functional groups such as CHO, C=O, C(O)OR, CN, NO2, and halogens.

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Confining H2 and D2 by adsorption in microporous carbons (single-wall carbon nanotubes and activated carbons) doped by K or Li

European Journal of Control ◽

10.3166/acsm.30.393-400 ◽

2005 ◽

Vol 30 (4) ◽

pp. 393-400 ◽

Cited By ~ 2

Author(s):

Szymon Los ◽

Philippe Azais ◽

Roland JM Pellenq ◽

Yannick Breton ◽

Olivier Isnard ◽

...

Keyword(s):

Carbon Nanotubes ◽

Activated Carbons ◽

Single Wall Carbon Nanotubes ◽

Single Wall Carbon ◽

Microporous Carbons

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Particle size effects in the selective hydrogenation of cinnamaldehyde over supported palladium catalysts

RSC Advances ◽

10.1039/c6ra17000e ◽

2016 ◽

Vol 6 (79) ◽

pp. 75541-75551 ◽

Cited By ~ 37

Author(s):

Feng Jiang ◽

Jian Cai ◽

Bing Liu ◽

Yuebing Xu ◽

Xiaohao Liu

Keyword(s):

Particle Size ◽

Size Effect ◽

Selective Hydrogenation ◽

Size Effects ◽

Palladium Catalysts ◽

Particle Size Effect ◽

Particle Size Effects ◽

Supported Palladium Catalysts ◽

Supported Palladium ◽

Palladium Particles

Palladium particles of different sizes obtained directly and indirectly by various methods were studied to clarify the particle size effect in the selective hydrogenation of cinnamaldehyde (CAL).

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Active-Passive Damping Characteristics of Extension and Shear Mode Piezoelectric Fiber Nano-Reinforced Composite (PFNRC)

Volume 1: Development and Characterization of Multifunctional Materials; Mechanics and Behavior of Active Materials; Bioinspired Smart Materials and Systems; Energy Harvesting; Emerging Technologies ◽

10.1115/smasis2017-3862 ◽

2017 ◽

Author(s):

Kepin Kavathia ◽

Manoj Settipalli ◽

Samikkannu Raja

Keyword(s):

Carbon Nanotubes ◽

Epoxy Matrix ◽

Effective Properties ◽

Past Research ◽

Piezoelectric Composite ◽

Passive Damping ◽

The Past ◽

Reinforced Composite ◽

Walled Carbon Nanotubes ◽

Piezoelectric Fiber

This paper presents a simulation-based study to investigate the damping properties of a novel piezocomposite, consisting of piezoelectric fiber and epoxy reinforced with randomly orientated double walled carbon nanotubes (DWCNT), termed as piezoelectric fiber nano reinforced composite (PFNRC). Authors have observed that the past research dealt with the effect of aligned single walled carbon nanotubes (CNT) on active damping of piezoelectric composite in extension mode (e13 and e33). It is known from the past research that DWCNT inclusions improve the passive damping of a composite. Therefore, the authors use DWCNT inclusions to study the active-passive damping of the piezoelectric composite, in this article. The random orientation of the DWCNT is considered to replicate the physical composite as it known that aligning CNTs in a single direction is not feasible due to fabrication constraints. A multistep homogenization method involving Method of Cells (MOC) is employed to obtain effective properties of PFNRC. A modified 3D-MOC is used to obtain the effective properties of epoxy matrix with DWCNT inclusions (DWCNT-epoxy), considering the effect of nano particle agglomeration. A 2D-MOC is then implemented with long fiber PZT as the active material and DWCNT-epoxy as the matrix. This procedure is followed for computing the effective material properties of extension (e33) as well as shear (e15) mode of PFNRC, when DWCNT inclusions are added into the epoxy matrix at different weight percentages. The constitutive equations are derived with the help of Maple and simulated in MATLAB. These results are used to compare the active-passive damping performance of the composites using a single degree of freedom damping model, employing Newmark’s numerical integration method. The active damping performance of the composites is evaluated by varying the displacement and velocity gains in a negative feedback system. The main focus of the study is to find the most efficient operating mode of the proposed composite for damping of structural vibrations.

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Carbons from Biomasic Waste and their Applications

C – Journal of Carbon Research ◽

10.3390/c5040059 ◽

2019 ◽

Vol 5 (4) ◽

pp. 59

Author(s):

Bedia ◽

Belver

Keyword(s):

Carbon Nanotubes ◽

Activated Carbons ◽

Graphene Nanosheets ◽

Two Dimensional ◽

One Dimensional ◽

Carbon Based

Carbon-based materials, such as chars, activated carbons, one-dimensional carbon nanotubes, and two-dimensional graphene nanosheets, have shown great potential for a wide variety of applications[...]

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N-doped carbon nanotubes for liquid-phase CC bond hydrogenation

Catalysis Today ◽

10.1016/j.cattod.2008.06.015 ◽

2008 ◽

Vol 138 (1-2) ◽

pp. 62-68 ◽

Cited By ~ 77

Author(s):

Julien Amadou ◽

Kambiz Chizari ◽

Matthieu Houllé ◽

Izabela Janowska ◽

Ovidiu Ersen ◽

...

Keyword(s):

Carbon Nanotubes ◽

Liquid Phase ◽

Bond Hydrogenation

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Predicting Aqueous Adsorption of Organic Compounds onto Biochars, Carbon Nanotubes, Granular Activated Carbons, and Resins with Machine Learning

Environmental Science & Technology ◽

10.1021/acs.est.0c02526 ◽

2020 ◽

Vol 54 (11) ◽

pp. 7008-7018 ◽

Cited By ~ 7

Author(s):

Kai Zhang ◽

Shifa Zhong ◽

Huichun Zhang

Keyword(s):

Machine Learning ◽

Carbon Nanotubes ◽

Organic Compounds ◽

Activated Carbons

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Recent Synthetic Advances on π-Extended Carbon Nanohoops

Synlett ◽

10.1055/s-0036-1588978 ◽

2017 ◽

Vol 28 (12) ◽

pp. 1383-1388 ◽

Cited By ~ 7

Author(s):

Huan Cong ◽

Yi Luan

Keyword(s):

Carbon Nanotubes ◽

Chemical Synthesis ◽

Rapid Progress ◽

Ring Closing Metathesis ◽

Bottom Up ◽

Reaction Method ◽

The Past

As a part of the ‘bottom-up’ campaign for the precise preparation of carbon nanotubes, the chemical synthesis of carbon nanohoops is observing rapid progress, with a number of milestone achievements, over the past decade. With simple carbon nanohoops (e.g. cycloparaphenylenes) now no longer elusive targets, this Synpacts article highlights latest synthetic advances to further build up nanohoops’ π-systems. Works reviewed herein include the study explaining the unsuccessful Scholl reaction method, the preparation of a carbon nanohoop consisting solely of hexabenzocoronene units, syntheses of π-extended carbon nanohoops employing the ring-closing metathesis method, and the anthracene photodimerization/cycloreversion method for anthracene-incorporated carbon nanohoop synthesis.1 Introduction2 Some Latest Syntheses of π-Extended Carbon Nanohoops3 Conclusion

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