Ultra-low loading of Ni in catalysts supported on mesoporous SiO2 and their performance in hydrodeoxygenation of palmitic acid

2020 ◽  
Vol 44 (6) ◽  
pp. 2435-2441 ◽  
Author(s):  
Diego Valencia ◽  
Citlalli Zenteno ◽  
Perla Morales-Gil ◽  
Leonardo Díaz-García ◽  
Diana Gómora-Herrera ◽  
...  
Keyword(s):  
Palmitic Acid ◽  
Heterogeneous Catalysts ◽  
Ni Catalysts ◽  
Biomass Feedstocks ◽  
Mesoporous Sio2

Ni catalysts supported on KIT-5 are attractive heterogeneous catalysts for hydrodeoxygenation of biomass feedstocks.

Template-Mediated Ni(II) Dispersion in Mesoporous SiO2 for Preparation of Highly Dispersed Ni Catalysts: Influence of Template Type

2017 ◽  
Vol 9 (22) ◽  
pp. 19335-19344 ◽  
Author(s):  
Xin Ning ◽  
Yiyuan Lu ◽  
Heyun Fu ◽  
Haiqin Wan ◽  
Zhaoyi Xu ◽  
...  
Keyword(s):  
Ni Catalysts ◽  
Highly Dispersed ◽  
Mesoporous Sio2

Effect of surface acidity and basicity of supported Ni catalysts on the N-alkylation of isopropylamine with isopropanol

2021 ◽  
Author(s):  
Shaozhong Li ◽  
Qing Guo ◽  
Jin Li ◽  
Yongke Hu
Keyword(s):  
Catalytic System ◽  
Heterogeneous Catalysts ◽  
Surface Acidity ◽  
Aliphatic Amines ◽  
Ni Catalysts ◽  
Supported Ni Catalysts ◽  
Acidity And Basicity ◽  
Alkylating Reagents ◽  
Supported Ni ◽  
Effect Of Surface

The N-alkylation of amines with alkylating reagents is widely used in the synthesis of aliphatic amines, which usually be catalyzed by homogeneous catalytic system. In this work, the heterogeneous catalysts...

scholarly journals Sintesis dan Karakterisasi Abu Kulit Alpukat sebagai Katalis Proses Transesterifikasi Minyak Goreng Bekas menjadi Biodiesel

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Azif Afandi ◽  
Lindia Riani ◽  
Yanna Syamsuddin ◽  
Zuhra Zuhra
Keyword(s):  
Palmitic Acid ◽  
Calcination Temperature ◽  
Heterogeneous Catalysts ◽  
Active Phase ◽  
Acid Number ◽  
Transesterification Reaction ◽  
Biodiesel Production ◽  
Homogeneous Catalyst ◽  
Waste Biomass

Biodiesel is synthesized through a transesterification reaction with the help of a catalyst and generally uses a homogeneous catalyst. Heterogeneous catalysts can be synthesized from waste biomass such as avocado peel through a calcination. The purpose of this study was to examine the effect of variations in calcination temperature (550, 650, and 750oC) on the performance of the catalyst for biodiesel production and to analyze the effect of differences in the amount of catalyst (4, 6, 8, and 10% by weight of oil) used in the transesterification process on biodiesel yield. The catalysts were characterized by XRD, SEM-EDX, and FTIR. The results of the characterization of the catalyst showed that the dominant active phase of the catalyst was potassium (K). The highest biodiesel yield was obtained when using avocado peel ash as a catalyst which was calcined at a temperature of 650oC and using 6% catalyst by weight of oil. In the transesterification reaction the composition of the biodiesel product was analyzed using GC-MS and resulted that the palmitic acid was the most abundant composition in biodiesel. The biodiesel products produced were characterized for its density, viscosity, and acid number and have met the standard of SNI 7182:2015.

What catalysis needs from the electron microscopist

1988 ◽  
Vol 46 ◽  
pp. 694-695
Author(s):  
Alexis T. Bell
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Catalyst Deactivation ◽  
Surface Composition ◽  
Internal Surface ◽  
Active Phase ◽  
Atomic Scale ◽  
Metal Catalyst ◽  
Internal Surface Area ◽  
Porous Support

Heterogeneous catalysts, used in industry for the production of fuels and chemicals, are microporous solids characterized by a high internal surface area. The catalyticly active sites may occur at the surface of the bulk solid or of small crystallites deposited on a porous support. An example of the former case would be a zeolite, and of the latter, a supported metal catalyst. Since the activity and selectivity of a catalyst are known to be a function of surface composition and structure, it is highly desirable to characterize catalyst surfaces with atomic scale resolution. Where the active phase is dispersed on a support, it is also important to know the dispersion of the deposited phase, as well as its structural and compositional uniformity, the latter characteristics being particularly important in the case of multicomponent catalysts. Knowledge of the pore size and shape is also important, since these can influence the transport of reactants and products through a catalyst and the dynamics of catalyst deactivation.

Electron holography of catalysts

1995 ◽  
Vol 53 ◽  
pp. 416-417
Author(s):  
A. K. Datye ◽  
D. S. Kalakkad ◽  
L. F. Allard ◽  
E. Völkl
Keyword(s):  
Heterogeneous Catalysts ◽  
High Surface ◽  
High Surface Area ◽  
Atomic Scale ◽  
Nano Particles ◽  
Phase Image ◽  
Electron Holography ◽  
Specimen Thickness ◽  
Phase Information ◽  
Particle Structure

The active phase in heterogeneous catalysts consists of nanometer-sized metal or oxide particles dispersed within the tortuous pore structure of a high surface area matrix. Such catalysts are extensively used for controlling emissions from automobile exhausts or in industrial processes such as the refining of crude oil to produce gasoline. The morphology of these nano-particles is of great interest to catalytic chemists since it affects the activity and selectivity for a class of reactions known as structure-sensitive reactions. In this paper, we describe some of the challenges in the study of heterogeneous catalysts, and provide examples of how electron holography can help in extracting details of particle structure and morphology on an atomic scale.Conventional high-resolution TEM imaging methods permit the image intensity to be recorded, but the phase information in the complex image wave is lost. However, it is the phase information which is sensitive at the atomic scale to changes in specimen thickness and composition, and thus analysis of the phase image can yield important information on morphological details at the nanometer level.

Quantitative nano-characterization of heterogeneous catalysts

1995 ◽  
Vol 53 ◽  
pp. 398-399
Author(s):  
P.A. Crozier ◽  
M. Pan
Keyword(s):  
Heterogeneous Catalysts ◽  
Low Dose ◽  
Imaging Techniques ◽  
Structural Features ◽  
Catalyst Characterization ◽  
New Developments ◽  
Double Phase ◽  
Phase Systems ◽  
Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

Palmitic acid

2011 ◽  
Author(s):  
Katrin Legg
Keyword(s):  
Palmitic Acid
Sign in / Sign up

Export Citation Format

Share Document