A Review of Heterogeneous Catalysts Preparation Methods

2021 ◽  
Vol 18 ◽  
Author(s):  
Israf Ud Din ◽  
Qazi Nasir ◽  
Mustapha D. Garba ◽  
Muhammad Usman ◽  
Abdulrahman I. Alharthi ◽  
...  
Keyword(s):  
Heterogeneous Catalysts ◽  
Industrial Revolution ◽  
Review Paper ◽  
Supported Catalysts ◽  
Reaction Rates ◽  
Production Costs ◽  
Synthesis Methods ◽  
Preparation Methods ◽  
Current Review ◽  
Catalysts Preparation

: Catalysts contribute significantly to the industrial revolution in terms of reaction rates and reduction in production costs. An extensive research has been documented in various industrial catalysis in the last few decades. The performance of catalysts has been influenced by many parameters including synthesis methods. The current work overviews the most common methods applied in the synthesis of supported catalysts. This review presents the detailed background, principle and mechanism of each preparation method. The advantages and limitations of each method have also been elaborated in details. In addition, the applications of each method in terms of catalysts synthesis have been documented in the current review paper.

scholarly journals 2D Graphene-TiO2 Composite and Its Photocatalytic Application in Water Pollutants

2021 ◽  
Vol 8 ◽  
Author(s):  
Xin Zhou ◽  
Xian Zhang ◽  
Yuemei Wang ◽  
Zhen Wu
Keyword(s):  
Visible Light ◽  
Catalytic Effect ◽  
Wide Bandgap ◽  
Synthesis Methods ◽  
Water Shortages ◽  
Preparation Methods ◽  
Research Attention ◽  
Current Review ◽  
Photocatalytic Application ◽  
Significant Research

To solve the global water shortages and serious water pollution problems, research on semiconductor photocatalysts has generated significant research attention. The degradation of pollutants by titanium dioxide (TiO2) exceeds other semiconductor materials. However, its wide bandgap restricts the photocatalytic reaction under visible light. The large specific surface area and good thermal conductivity of graphene yielded an effective graphene-TiO2 catalyst combination effective under visible light. 2D graphene-TiO2 composites (2D-GTC) have shown promise, so a study of the preparation methods, mechanism and catalytic effect of different pollutants on this material was undertaken. In this current review, the characteristics of different graphene and TiO2 composites and their preparation methods, as well as the effects of different synthesis methods on the catalyst are introduced. The reaction mechanism of 2D-GTC catalysts, the degradation effects of different pollutants in water are all reviewed.

scholarly journals Recent Progress in the Application of Hydroxyapatite for the Adsorption of Heavy Metals from Water Matrices

Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 6898
Author(s):  
Roxana Ioana Brazdis ◽  
Irina Fierascu ◽  
Sorin Marius Avramescu ◽  
Radu Claudiu Fierascu
Keyword(s):  
Heavy Metals ◽  
Recent Progress ◽  
Review Paper ◽  
Morphological Characteristics ◽  
Critical Issue ◽  
Synthesis Methods ◽  
Current Review ◽  
Removal Of Heavy Metals ◽  
Materials Used ◽  
Adsorbent Materials

Wastewater treatment remains a critical issue globally, despite various technological advancements and breakthroughs. The study of different materials and technologies gained new valences in the last years, in order to obtain cheap and efficient processes, to obtain a cleaner environment for future generations. In this context, the present review paper presents the new achievements in the materials domain with highlights on apatitic materials used for decontamination of water loaded with heavy metals. The main goal of this review is to present the adsorptive removal of heavy metals using hydroxyapatite-based adsorbents, offering a general overview regarding the recent progress in this particular area. Developing the current review, an attempt has been made to give appropriate recognition to the most recent data regarding the synthesis methods and targeted pollutants, including important information regarding the synthesis methods and precursors, morphological characteristics of the adsorbent materials and effectiveness of processes.

Potential Uses of Vinegar as a Medicine and Related in vivo Mechanisms

2016 ◽  
Vol 86 (3-4) ◽  
pp. 127-151 ◽  
Author(s):  
Zeshan Ali ◽  
Zhenbin Wang ◽  
Rai Muhammad Amir ◽  
Shoaib Younas ◽  
Asif Wali ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Review Paper ◽  
Heart Diseases ◽  
Folk Medicine ◽  
Active Role ◽  
Current Review ◽  
Different Types ◽  
Positive Effect

While the use of vinegar to fi ght against infections and other crucial conditions dates back to Hippocrates, recent research has found that vinegar consumption has a positive effect on biomarkers for diabetes, cancer, and heart diseases. Different types of vinegar have been used in the world during different time periods. Vinegar is produced by a fermentation process. Foods with a high content of carbohydrates are a good source of vinegar. Review of the results of different studies performed on vinegar components reveals that the daily use of these components has a healthy impact on the physiological and chemical structure of the human body. During the era of Hippocrates, people used vinegar as a medicine to treat wounds, which means that vinegar is one of the ancient foods used as folk medicine. The purpose of the current review paper is to provide a detailed summary of the outcome of previous studies emphasizing the role of vinegar in treatment of different diseases both in acute and chronic conditions, its in vivo mechanism and the active role of different bacteria.

An Overview of Metal-organic Frameworks-based Acid/Base Catalysts for Biofuel Synthesis

2020 ◽  
Vol 24 (16) ◽  
pp. 1876-1891
Author(s):  
Qiuyun Zhang ◽  
Yutao Zhang ◽  
Jingsong Cheng ◽  
Hu Li ◽  
Peihua Ma
Keyword(s):  
Alternative Fuels ◽  
Heterogeneous Catalysts ◽  
Supported Catalysts ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
Flexible Structures ◽  
Biodiesel Production ◽  
Biodiesel Synthesis ◽  
Metal Organic ◽  
Organic Framework

Biofuel synthesis is of great significance for producing alternative fuels. Among the developed catalytic materials, the metal-organic framework-based hybrids used as acidic, basic, or supported catalysts play major roles in the biodiesel production. This paper presents a timely and comprehensive review of recent developments on the design and preparation of metal-organic frameworks-based catalysts used for biodiesel synthesis from various oil feedstocks, including MILs-based catalysts, ZIFs-based catalysts, UiO-based catalysts, Cu-BTC-based catalysts, and MOFs-derived porous catalysts. Due to their unique and flexible structures, excellent thermal and hydrothermal stability, and tunable host-guest interactions, as compared with other heterogeneous catalysts, metal-organic framework-based catalysts have good opportunities for application in the production of biodiesel at industrial scale.

Laser electrodispersion as a new chlorine-free method for the production of highly effective metal-containing supported catalysts

2012 ◽  
Vol 84 (3) ◽  
pp. 495-508 ◽  
Author(s):  
Ekaterina S. Lokteva ◽  
Anton A. Peristyy ◽  
Natalia E. Kavalerskaya ◽  
Elena V. Golubina ◽  
Lada V. Yashina ◽  
...  
Keyword(s):  
Gas Phase ◽  
High Stability ◽  
Heterogeneous Catalysts ◽  
Supported Catalysts ◽  
Promising Technique ◽  
Wet Impregnation ◽  
Oxide Supports ◽  
Highly Active ◽  
Specific Catalytic Activity ◽  
Free Metal

Laser electrodispersion (LED) of metals is a promising technique for the preparation of heterogeneous catalysts as an alternative to wet impregnation of supports with the corresponding salt solutions. The LED technique can be used to deposit highly active chloride- and nitrate-free metal nanoparticles onto carbon or oxide supports. We report preparation and properties of new Ni-, Pd-, and Au-containing alumina-supported catalysts with low metal loadings (10–3–10–4 % mass) and their comparison with the previously studied carbon (Sibunit) supported systems. The catalysts demonstrate high stability and extremely high specific catalytic activity (by 2–3 orders of magnitude higher than for traditional catalysts) in the gas-phase hydrodechlorination (HDC) of chlorobenzene (CB).

Crystal Engineering for Catalysis

2018 ◽  
Vol 9 (1) ◽  
pp. 283-309 ◽  
Author(s):  
Jeffrey D. Rimer ◽  
Aseem Chawla ◽  
Thuy T. Le
Keyword(s):  
Crystal Engineering ◽  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Computational Design ◽  
Crystal Nucleation ◽  
Synthesis Methods ◽  
Crystalline Materials ◽  
Simultaneous Control ◽  
Metal Organic ◽  
Controlled Environments

Crystal engineering relies upon the ability to predictively control intermolecular interactions during the assembly of crystalline materials in a manner that leads to a desired (and predetermined) set of properties. Economics, scalability, and ease of design must be leveraged with techniques that manipulate the thermodynamics and kinetics of crystal nucleation and growth. It is often challenging to exact simultaneous control over multiple physicochemical properties, such as crystal size, habit, chirality, polymorph, and composition. Engineered materials often rely upon postsynthesis (top-down) processes to introduce properties that would otherwise be challenging to attain through direct (bottom-up) approaches. We discuss the application of crystal engineering to heterogeneous catalysts with a focus on four general themes: ( a) tailored nanocrystal size, ( b) controlled environments surrounding active sites, ( c) tuned morphology with well-defined facets, and ( d) hierarchical materials with disparate pore size and active site distributions. We focus on nonporous materials, including metals and metal oxides, and two classes of porous materials: zeolites and metal organic frameworks. We review novel synthesis methods involving synergistic experimental and computational design approaches, the challenges facing catalyst development, and opportunities for future advancement in crystal engineering.

Towards Mg based light materials of future: Properties, applications, problems and their mitigation.

2021 ◽  
pp. 1-43
Author(s):  
Annayath Maqbool ◽  
Noor Zaman Khan ◽  
Arshad Noor Siddiquee
Keyword(s):  
Corrosion Resistance ◽  
Review Paper ◽  
Weight Ratio ◽  
High Strength ◽  
Low Density ◽  
Widespread Application ◽  
Potential Barriers ◽  
Current Review ◽  
Processing Techniques ◽  
Corrosive Resistance

Abstract The use of lighter materials is one of the efficient means to mitigate the increasing demands on fuel resources, reduce CO2 emissions. Mg is one of the lightest material available and possesses exciting range of properties such as low density and high strength to weight ratio. Despite such exciting properties, the applications of Mg and its alloys were very limited in aerospace, automotive and biomedical industries but recently the application is picking-up. The restricted application is attributed to anisotropy, poor corrosive resistance and inflammability of Mg. The current review addresses the barriers limiting the widespread application of Mg based materials. Furthermore, the mitigation of the problems of anisotropy, poor corrosion resistance, ductility and inflammability of Mg are critically reviewed. The findings of this research provide insights of the processing techniques, properties and how to address the potential barriers of limited applications. The review paper will assist and motivate the researchers to ponder and overcome numerous problems related to Mg and its alloys by understanding the importance of each problem discussed in this review. An attempt has also been made to arrange research status on issues and the mitigation thereof with respect to Mg and its alloys as single reference point.

Carbon Nanomaterials

2019 ◽  
pp. 1-33 ◽  
Author(s):  
Ezgi Ismar ◽  
A.Sezai Sarac
Keyword(s):  
Surface Area ◽  
Carbon Nanofibers ◽  
Industrial Revolution ◽  
Carbon Nanomaterials ◽  
Surface Reactivity ◽  
Synthesis Methods ◽  
Carbon Based Nanomaterials ◽  
Carbon Based

Development of materials always plays a key role in the civilization of the societies. After the industrial revolution, material-based technologies received attention. Nanotechnology has a revolutionary part in the development of industries. Developing technologies cannot be considered without the usage of nanomaterials. Nano-sized materials have different properties than their bulk forms basically because of the increased surface area, surface reactivity, and energy according to decreased size. Carbon-based nanomaterials have a variety of possible application areas from biosensors to aviation. This compact review put a great deal of emphasis on the position of carbon nanomaterials: CNTs, graphene, and carbon nanofibers together with their main synthesis methods and their application areas. The reader can get a quick idea about the basics of CNTs, graphene, and carbon nanofibers and their fabrication techniques.

scholarly journals A Review on Synthesis of Mullite Ceramics from Industrial Wastes

Recycling ◽  
2019 ◽  
Vol 4 (3) ◽  
pp. 39 ◽  
Author(s):  
Choo ◽  
Mohd Salleh ◽  
Kok ◽  
Matori
Keyword(s):  
Thermal Expansion ◽  
Mechanical Strength ◽  
Metal Oxides ◽  
Review Paper ◽  
Starting Material ◽  
Industrial Wastes ◽  
Chemical Additives ◽  
Material Source ◽  
Preparation Methods ◽  
Mullite Ceramics

Some industrial wastes are shown to be useful in the production of mullite ceramics. These industrial wastes are rich in certain metal oxides such as silica (SiO2) and alumina (Al2O3). This gives wastes the potential to be used as a starting material source for mullite ceramics preparation. The purpose of this review paper is to compile and review various mullite ceramics preparation methods that utilized a variety of industrial wastes as starting materials. This review also describes the sintering temperatures and chemical additives used in the preparation and its effects. A comparison of both mechanical strength and thermal expansion of the reported mullite ceramics prepared from various industrial wastes were also addressed in this work.

Sign in / Sign up

Export Citation Format

Share Document