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Topic Review
Metallophthalocyanines
Since the serendipitous discovery of phthalocyanines (Pcs), at the beginning of the 20th century, growing attention has been devoted to the ubiquitous catalytic properties and applications of Pcs and Pcs coordinated with metal ions, Metallophthalocyanines (MPcs). In fact, these old synthetic dyes have been very attractive in the view of academic research, but mainly for catalytic industrial purposes as these dyes are easily accessible on a large scale, are robust under harsh reaction conditions, show high activity, and can be recovered and recycled. The success and diversity of MPcs as catalysts over different substrates are mostly attributed to their high structural flexibility in terms of metals and electronic properties of the phthalocyanine ligands.
  • 1.9K
  • 20 Feb 2021
Topic Review
Hydrometallurgy and Germanium Recovery from Secondary Resources
Though nowadays germanium do not reach the range of popularity than other metals, i.e. rare earth elements, its utility in target industries makes of it also a strategic metal. Though germanium can be found in a series of raw materials, the principal source for its recovery is from secondary wastes of the zinc industry, also, the recycle of germanium-bearing waste materials is becoming of interest. In this recovery the size of the target materials because the diffusion and reaction are to be considered, Hydrometallurgy is performing a key role to the successful achievement of this goal. The present work reviews the most recent applications (2023 and 2024 years) of hydrometallurgical operations on the recovery of germanium from different solid and liquid sources.  
  • 1.9K
  • 30 Apr 2024
Topic Review
Water Remediation
Chemical pollution of water has raised great concerns among citizens, lawmakers, and nearly all manufacturing industries. As the legislation addressing liquid effluents becomes more stringent, water companies are increasingly scrutinized for their environmental performance. In this context, emergent contaminants represent a major challenge, and the remediation of water bodies and wastewater demands alternative sorbent materials. One of the most promising adsorbing materials for micropolluted water environments involves cyclodextrin (CD) polymers and cyclodextrin-containing polysaccharides. 
  • 1.9K
  • 22 Feb 2021
Topic Review
Nitroaromatic Antibiotics
Nitroaromatic antibiotics show activity against anaerobic bacteria and parasites, finding use in the treatment of Heliobacter pylori infections, tuberculosis, trichomoniasis, human African trypanosomiasis, Chagas disease and leishmaniasis.
  • 1.8K
  • 01 Apr 2021
Topic Review
Treatment Methods for Dye-Contaminated Effluents
Advancements in textile dyeing technologies have introduced novel categories of dyes that have deleterious effects on ecosystems. Primarily, azo dyes represent the majority of synthetic dyes employed in textiles and in the realms of culinary and miscellaneous applications. Traditionally, these dyes infiltrate the environment via discharged contaminated effluents such as wastewater from industrial facilities. The contaminated discharged effluent exerts a pervasive impact on ecosystems, engendering pernicious afflictions in both human and faunal populations. Several treatment methodologies are employed for the eradication of contaminants from natural water resources and wastewater, encompassing all phases within water and wastewater treatment infrastructures. The evolution of each treatment stage is intricately linked to the escalating demand for potable water of impeccable quality. Water treatment methods such as Coagulation and Flocculation, Photocatalytic Degradation, Ion Exchange, Electrochemical Technique, Membrane Filtration, Electrodialysis Process, Biodegradation Techniques, and Adsorption are covered in detail, alongside the impacts of bio-based activated carbon as an adsorbent for azo dye. 
  • 1.8K
  • 26 Sep 2023
Topic Review
Hydrogen Production via Chemical Looping Water-Splitting
Hydrogen is an important green energy source and chemical raw material for various industrial processes. The major technique of hydrogen production is steam methane reforming (SMR), which suffers from high energy penalties and enormous CO2 emissions. As an alternative, chemical looping water-splitting (CLWS) technology represents an energy-efficient and environmentally friendly method for hydrogen production. The key to CLWS lies in the selection of suitable oxygen carriers (OCs) that hold outstanding sintering resistance, structural reversibility, and capability to release lattice oxygen and deoxygenate the steam for hydrogen generation. 
  • 1.8K
  • 26 Apr 2023
Topic Review
Zooceuticals and Cosmetic Ingredients Derived from Animals
Many substances derived from animals are used as ingredients in the cosmetic industry and constitute a particular type of product: zooceuticals. The main ingredients used can come from insects, such as snail slime; land animals, such as lanolin; and marine animals, such as marine collagen. Today, they are used less than in the past for hygienic–sanitary, ethical, and ecological reasons. Moreover, some can give rise to irritative or allergic dermatitis. However, they still represent a fraction of the common ingredients in certain types of cosmetic products today.
  • 1.8K
  • 07 Mar 2022
Topic Review
Nanoencapsulated Phase-Change Materials
Phase-change materials (PCMs) are becoming more widely acknowledged as essential elements in thermal energy storage, greatly aiding the pursuit of lower building energy consumption and the achievement of net-zero energy goals. PCMs are frequently constrained by their subpar heat conductivity, despite their expanding importance. 
  • 1.8K
  • 30 Nov 2023
Topic Review
Salts Hydrates and Composites
Salt hydrates are alloys of salts and water. Salt hydrates display high theoretical energy densities, which are promising materials in thermal energy storage (TES).
  • 1.8K
  • 25 Jan 2022
Topic Review
Screen-Printed Electrodes as Transducers
In the last decades, sensors based on screen-printed electrodes (SPEs) have gained increasing importance because of their advantageous characteristics, such as low-cost, disposability, ease of use and portability, which allow fast analysis in point-of-need scenarios. The main characteristics of SPEs as electrochemical transducers for biosensors are described below.
  • 1.8K
  • 13 Apr 2021
Topic Review
Antibiotics in Poultry Production
The utilization of antibiotics in feed has been reevaluated since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can easily be spread within microbial communities. Multiple countries have introduced bans or severe restrictions on the non-therapeutic use of antibiotics. Since the use of antibiotics may have a positive influence on poultry performance, excessive use as growth promoters harms human health. This has therefore warranted the urgent need for alternatives.
  • 1.8K
  • 26 Oct 2020
Topic Review
Conversion of 5-hydroxymethylfurfural to 2,5-dimethylfuran
Many researchers have extensively explored selective hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF), and some of them were able to achieve high conversion and a high yield of DMF under certain reaction conditions. However, the main challenge is to reduce the operational cost using cost-effective catalysts as an alternative to the expensive noble metals. Overall, the approach of using bifunctional catalysts is an important direction for catalysis in general and particularly for reactions that require significantly different types of elementary steps as part of an overall reaction. For this reason, efforts to use the rational design of interfaces will become important for supplementing the promising initial work in demonstrating bifunctional catalysis for catalytic transformations of biomass-derived 5-hydroxymethylfurfural to a potential liquid fuel, 2,5-dimethylfuran. Apart from the different types of metal and support, it was also observed that reaction conditions, namely the type of solvent, H2 donor, reaction temperature, reaction time, and H2. 
  • 1.7K
  • 28 Jun 2022
Topic Review
Electrostatic Repulsion Reversed-Phase Liquid Chromatography
Electrostatic Repulsion Reversed-Phase Liquid Chromatography (ERRP) allows the elution of bases in protonated form without peak distorsion (as commonly happen in reversed phase) due to the presence of positive charges in the chromatographic system. 
  • 1.7K
  • 05 Aug 2021
Topic Review
Solar Reactors for Hydrogen Production
Green hydrogen production is at the core of the transition away from conventional fuels. Along with popularly investigated pathways for hydrogen production, thermochemical water splitting using redox materials is an interesting option for utilizing thermal energy, as this approach makes use of temperature looping over the material to produce hydrogen from water. Solar reactors have conventionally been used for such reactions, as temperatures up to 2000 °C can be reached, which are beneficial for the reduction of the redox material. 
  • 1.7K
  • 27 Apr 2022
Topic Review
Nanostructured Materials for Uranium Removal
Groundwater is commonly used as a drinking water resource all over the world. Therefore, groundwater contamination by toxic metals is an important issue of utmost concern for public health, and several technologies are applied for their effective removal, such as coagulation, ion exchange, adsorption, and membrane applications like reverse osmosis. Adsorption is acknowledged as a simple, effective and economic technology, which has received increased interest recently, despite certain limitations regarding operational applications. The respective scientific efforts have been specifically focused on the development and implementation of novel nano-structured adsorbent materials, which may offer extensive specific surface areas, much higher than the conventional adsorbents, and hence, are expected to present higher removal efficiencies of pollutants. In this paper, the recent developments of nanomaterial applications for uranium removal from groundwaters are critically reviewed. Particularly, the use of novel composite materials, based mainly on hybrid metallic oxide nanoparticles and on composites based on graphene oxide (GO) (i.e., graphene-based hybrids), showed promising evidences to achieve efficient removal of toxic metals from water sources, even in full scale applications.
  • 1.7K
  • 12 May 2020
Topic Review
Multi-Material 3D Printing of Functional Ceramic Devices
As an emerging technology, multi-material 3D printing offers increased complexity and greater freedom in the design of functional ceramic devices because of its unique ability to directly construct arbitrary 3D parts that incorporate multiple material constituents without an intricate process or expensive tools.
  • 1.7K
  • 17 Nov 2022
Topic Review
Hybrid Engineered Water–Polymer Flooding (EWPF)
Hybrid EWPF has been experimentally investigated for both sandstone and carbonate reservoirs by various researchers. The idea behind hybrid EWPF is to enhance oil recovery by the combined effect of optimized injection water composition and polymer flooding. Most of the studies have shown the synergistic benefits of the hybrid method in terms of two- to four-fold decreases in the polymer adsorption, leading to 30–50% reductions in polymer consumption, making the project economically viable for carbonates. EWPF has resulted in 20–30% extra oil recovery in various carbonate coreflood experiments compared to high-salinity water flooding.
  • 1.6K
  • 26 Oct 2020
Topic Review
Nanofilms
Nanofilms are thin films that are composed of nanoscale materials and have thicknesses typically ranging from a few nanometers to a few hundred nanometers. Nanofilms have unique properties that make them useful in a wide range of applications, including electronics, biomedicine, manufacturing, food, surface protection, and environmental protection. Nanofilms can be made from a variety of materials, including metals, ceramics, polymers, and composites. They can be designed with specific properties, such as high surface area, improved mechanical and chemical stability, and tailored optical and electrical properties. These unique properties of nanofilms make them useful in a wide range of applications.
  • 1.6K
  • 06 Feb 2023
Topic Review
Activation Persulfate by Various Iron-Based Catalysts
Advanced oxidation technology of persulfate is a new method to degrade wastewater. As the economy progresses and technology develops, increasingly more pollutants produced by the paper industry, printing and dyeing, and the chemical industry are discharged into water, causing irreversible damage to water. Methods and research directions of activation persulfate for wastewater degradation by a variety of iron-based catalysts are reviewed. This entry describes the merits and demerits of advanced oxidation techniques for activated persulfate by iron-based catalysts. In order to promote the development of related research work, the problems existing in the current application are analyzed.
  • 1.6K
  • 24 Jan 2022
Topic Review
Catalysts in Fischer-Tropsch Synthesis
With an increase in energy consumption globally, Fischer-Tropsch (FT) synthesis is a good alternative for producing fuels and chemicals from coal, natural gas or biomass. Among them, coal to liquids has been put into production in countries that have large coal reserves. In this process, Fe-based catalysts are commonly used due to their earth abundance, comparatively wide operation range and ready availability to handle low H2/CO ratio from coal. 
  • 1.6K
  • 13 Jul 2023
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