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Topic Review
Processes for Obtaining Syngas and Hydrogen
The growing demand for high-quality chemical products has already stimulated an increased interest in the conversion of hydrocarbon gases (natural gas, methane, biogas) into motor fuels and high value-added chemical products, as well as into hydrogen, which is increasingly in demand on the market. The conversion of natural gas into hydrogen and syngas is still the most complex and costly stage of modern gas chemical processes, the low efficiency of which hinders the development of modern gas chemistry. 
  • 2.2K
  • 14 Apr 2023
Topic Review
Switchable Solvents
Switchable solvents are a special class of solvents that have the ability to switch between different forms and properties, depending on external stimuli. The most common type of switchable solvents are called "ionic liquids" which are liquids made up of ions that are in a liquid state at room temperature. These solvents have unique properties that make them attractive for a wide range of applications, such as green chemistry, separation and purification processes, and energy storage. Switchable solvents are a class of solvents that can undergo reversible changes in their physical and chemical properties in response to external stimuli, such as temperature, pressure, or pH. They have gained significant attention in recent years due to their potential as more sustainable and efficient alternatives to traditional solvents in a range of applications, including industrial processes and chemical synthesis. Switchable solvents can be classified into two main categories: reversible ionic liquids (RILs) and switchable polarity solvents (SPSs). RILs are a type of switchable solvent that can change from a liquid to a solid or a gas, depending on the applied stimulus. This reversible phase transition is due to the formation or disruption of ionic interactions between the solvent molecules. RILs have been used in a range of applications, including the separation of chemicals, catalysis, and energy storage. SPSs, on the other hand, are solvents that can switch between polar and non-polar states in response to a stimulus, such as a change in pH or temperature. This switch in polarity can be used to selectively extract or dissolve different types of molecules, making them useful in a range of industrial processes, including extraction, separation, and purification. One of the main advantages of switchable solvents is their potential to reduce the environmental impact of chemical processes by replacing traditional solvents that are toxic or have a high carbon footprint. They can also improve process efficiency by reducing the need for multiple solvents and simplifying the solvent recovery process
  • 2.2K
  • 24 Mar 2023
Topic Review
Trends in Cu-Catalyzed Ar-Xs Transformations with Amines
Aromatic compounds (Ar-Xs) are technologically important inert low-cost solvents (chlorobenzene or o-dichlorobenzene) and intermediates for the manufacture of flame-retardant polymers used in electronics and furniture. Furthermore, Ar-Xs are the chemicals necessary for the production of industrially important dyes, pigments, and a broad group of biologically active species such as pesticides and drugs. Utilization of Ar-Xs as arylating agents based on Cu-catalyzed substitution of bound halogen (X) applying different nucleophiles serves as the technique for production of a broad scale of useful chemicals.
  • 2.2K
  • 16 Sep 2022
Topic Review
High-Performance Liquid Chromatography Analysis of Coffee-Based Products
Coffee is a very popular beverage worldwide. However, its composition and characteristics are affected by a number of factors, such as geographical and botanical origin, harvesting and roasting conditions, and brewing method used. As coffee consumption rises, the demands on its high quality and authenticity naturally grows as well. Unfortunately, at the same time, various tricks of coffee adulteration occur more frequently, with the intention of quick economic profit. Many analytical methods have already been developed to verify the coffee authenticity, in which the high-performance liquid chromatography (HPLC) plays a crucial role, especially thanks to its high selectivity and sensitivity. 
  • 2.2K
  • 14 Nov 2022
Topic Review
Ceramic-Based Hybrid Supercapacitors
Supercapacitors (SCs) have attracted considerable attention among various energy storage devices due to their high specific capacity, high power density, long cycle life, economic efficiency, environmental friendliness, high safety, and fast charge/discharge rates. SCs are devices that can store large amounts of electrical energy and release it quickly, making them ideal for use in a wide range of applications. They are often used in conjunction with batteries to provide a power boost when needed and can also be used as a standalone power source. They can be used in various potential applications, such as portable equipment, smart electronic systems, electric vehicles, and grid energy storage systems.
  • 2.2K
  • 02 Nov 2022
Topic Review
Microbially-Induced Desaturation and Carbonate Precipitation
Microbially induced carbonate precipitation (MICP) has been proposed as a sustainable approach to solve various environmental, structural, geotechnical and architectural issues. In the last decade, a ubiquitous microbial metabolism, nitrate reduction (also known as denitrification) got attention in MICP research due to its unique added benefits such as simultaneous corrosion inhibition in concrete and desaturation of porous media. The latter even upgraded MICP into a more advanced concept called microbially induced desaturation and precipitation (MIDP) which is being investigated for liquefaction mitigation.
  • 2.1K
  • 01 Sep 2021
Topic Review
Boron Used in Lithium Batteries Electrolytes
Boron and boron compounds have been extensively studied together in the history and development of lithium batteries, which are crucial to decarbonization in the automotive industry and beyond. As early as the year 2000, lithium bis(oxalato)borate, also known as LiBOB, was first reported for synthesis and use in electrolytes of LIBs. Because of the merits of being halide-free and more thermally stable than LiPF6, LiBOB has been proven beneficial either as a direct replacement for LiPF6 or as an electrolyte additive (2 wt%) in a nickel cobalt aluminum (NCA)—graphite system.
  • 2.1K
  • 03 Nov 2022
Topic Review
Physicochemistry of Deep Eutectic Solvents
Deep eutectic solvents (DESs), considered as one of the greenest families of solvents, are used in many fields, such as organic synthesis, (bio)catalysis, electrochemistry, and (bio)medicine.
  • 2.1K
  • 17 May 2023
Topic Review
Hydrogen Adsorption in Metal–Organic Frameworks
The development of hydrogen technologies and a wider use of hydrogen fuel cell systems require new materials that can store large amounts of hydrogen at relatively low pressures with small volume, low weight, and fast kinetics for recharging. Among the most challenging materials for hydrogen storage are porous coordination polymers, also called metal–organic frameworks (MOFs). MOFs are two- or three-dimensional porous crystalline materials with infinite lattices. As a result of their ultra-high surface area values (more than 2500 m2·g–1 measured by the Brunauer–Emmett–Teller (BET) approach), they were found to be promising gas adsorbers for small gaseous molecules, including CH4, CHCl3, CCl4, C6H6, C6H12, CO2, Ar, N2, and H2. The main benefit of MOFs is their reversible and high-rate hydrogen adsorption process. A reasonable number of H2 molecules inside the body of MOFs may only be obtained at very low temperatures. To date, MOFs have shown significant progress in applications of gas separation, catalysis, and coordination chemistry.
  • 2.1K
  • 09 Aug 2021
Topic Review
Alginate Application in Drug Delivery
Alginates are generally used in the food, beverage, cosmetic, paper, textile printing, and pharmaceutical industries. They have been utilized as stabilizers, thickeners, emulsifiers, and hydration and gelling agents. The main use of alginate in the biomedical industry is mainly focused on hydrogels used in wound healing, drug delivery, and tissue regeneration. The broad range of applications is due to its biocompatibility, low toxicity and relatively low-cost consumption, and structural similarity to the extracellular matrices of living tissue.
  • 2.1K
  • 22 Dec 2021
Topic Review
Peroxyacetic Acid Pretreatment in Lignocellulose Biorefinery
The stubborn and complex structure of lignocellulose hinders the valorization of each component of cellulose, hemicellulose, and lignin in the biorefinery industries. Therefore, efficient pretreatment is an essential and prerequisite step for lignocellulose biorefinery. A considerable number of studies have focused on peroxyacetic acid (PAA) pretreatment in lignocellulose fractionation and some breakthroughs have been achieved in recent decades. 
  • 2.1K
  • 12 Oct 2022
Topic Review
Sustainable Synthesis of MXenes
MXenes provide a major drawback involving environmentally harmful and toxic substances for its general fabrication in large-scale production and employing a high-temperature solid-state reaction followed by selective etching. Meanwhile, how MXenes are synthesized is essential in directing their end uses. Therefore, making strategic approaches to synthesize greener, safer, more sustainable, and more environmentally friendly MXenes is imperative to commercialize at a competitive price. 
  • 2.1K
  • 17 Jan 2023
Topic Review
Shape Memory Polyurethane
The inherent capability to deform and reform in a predefined environment is a unique property existing in shape memory polyurethane. The intrinsic shape memory ability of the polyurethane is due to the presence of macro domains of soft and hard segments in its bulk, which make this material a potential candidate for several applications. This entry is focused on manifesting the applicability of shape memory polyurethane and its composites/blends in various domains, especially to human health such as shielding of electromagnetic interference, medical bandage development, bone tissue engineering, self-healing, implants development, etc. 
  • 2.0K
  • 30 Oct 2020
Topic Review
Solar Energy Systems into Seawater Desalination
Solar energy, amongst all renewable energies, has attracted inexhaustible attention all over the world as a supplier of sustainable energy. The energy requirement of major seawater desalination processes such as multistage flash (MSF), multi-effect distillation (MED) and reverse osmosis (RO) are fulfilled by burning fossil fuels, which impact the environment significantly due to the emission of greenhouse gases. The integration of solar energy systems into seawater desalination processes is an attractive and alternative solution to fossil fuels. 
  • 2.0K
  • 29 Sep 2022
Topic Review
Copper Chrome Arsenate Water-Borne Solution
Copper chrome arsenate (CCA) water-borne solution used to make timber is highly resistant to pests and fungi, in particular, wood products designed for outdoor use. Nowadays, CCA is a restricted chemical product in most countries, since potential environmental and health risks were reported due to dermal contact with CCA residues from treated structures and the surrounding soils. However, large quantities of CCA-treated timber are still in use in framings, outdoor playground equipment, landscaping, building poles, jetty piles, and fencing structures around the world, thus CCA remains a source of pollutants to the environment and of increasing toxic metal/metalloid exposure (mainly in children). International efforts have been dedicated to the treatment of materials impregnated with CCA, however not only does some reuse of CCA-treated timber still occur, but also existing structures are leaking the toxic compounds into the environment, with impacts on the environment and animal and human health.
  • 2.0K
  • 10 Jun 2021
Topic Review
Thiol-and Disulfide-Based Stimulus-Responsive Soft Materials
Thiols (RSH) and disulfides (RSSR) are components of many proteins, biopolymers, and biomolecules.  Many can be interconverted by simple oxidation and reduction reactions that change drastically their properties and those of host molecules of which they are a part.
  • 2.0K
  • 11 Jun 2021
Topic Review
Catalysts for Glycerol Reforming
The valuable products produced from glycerol transformation have become a research route that attracted considerable benefits owing to their huge volumes as well as a myriad of chemical and biological techniques for transforming glycerol into high-value compounds, such as fuel additives, biofuels, precursors, and other useful chemicals, etc. Steam, aqueous, and autothermal reforming processes have been primarily investigated in glycerol reforming. An update on glycerol reforming is given, with an exclusive focus on the various catalyst's performance in designing reaction operation conditions.
  • 1.9K
  • 25 Jul 2022
Topic Review
Reaction Mechanisms of Glycerol Hydrogenolysis to 1,2-Propylene Glycol
The development and growth of the biodiesel industry has led to a parallel market for the supply of glycerol, its main by-product. Its wide availability and relatively low cost as a raw material make glycerol a basic component for obtaining various chemical products and allows for the development of a biorefinery around biodiesel plants, through the technological integration of different production processes. Catalytic hydrogenolysis is an interesting alternative because it leads to the formation of 1,2-propylene glycol (1,2-PG) and other glycols such as 1,3-propylene glycol (1,3-PG) and ethylene glycol (EG), widely used in the chemical industry. In the following text, the main reaction mechanisms of glycerol hydrogenolysis are presented, focusing on the production of 1,2-PG, in order of chronological appearance.
  • 1.9K
  • 10 May 2023
Topic Review
Surface Acoustic Wave Sensors Materials
Since their development, surface acoustic wave (SAW) devices have attracted much research attention due to their unique functional characteristics, which make them appropriate for the detection of chemical species. The scientific community has directed its efforts toward the development and integration of new materials as sensing elements in SAW sensor technology with a large area of applications.
  • 1.9K
  • 28 Jun 2021
Topic Review
Sample Preparation for Cosmetics Analysis
Traditional cosmetics sample preparation techniques involve liquid–liquid extraction (LLE) and solid–liquid extraction (SLE). In last years, modern sample extraction techniques are advancing towards fast sample processing, easy automatization, as well as a reduction in organic solvent volumes, in agreement with the green chemistry principles in two ways (i) the miniaturization of conventional procedures allowing a reduction of the solvents and reagents consumption and (ii) the development and application of sorbent- and liquid-based microextraction technologies to obtain a high analyte enrichment, avoiding or significantly reducing the use of organic solvents.
  • 1.9K
  • 24 Nov 2021
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