Low-cost by-products from agricultural, household and industrial sectors have been recognized as a sustainable solution for wastewater treatment. They allow achieving the removal of pollutants from ...wastewater and at same time to contribute to the waste minimization, recovery and reuse. Despite numerous reviews have been published in the last few years, a direct comparison of data obtained using different sorbents is difficult nowadays because of inconsistencies in the data presentation. In this context, the aim of the study was to revise the current literature concerning the application of low-cost adsorbents for wastewater treatment highlighting, systematically, both adsorbents characteristics and adsorption capacities. For this scope, low-cost sorbents have been divided into the following five groups: (i) Agricultural and household wastes, (ii) industrial by-products, (iii) sludge, (iv) sea materials, (v) soil and ore materials and (vi) novel low-cost adsorbents. The affinity of sorbents in removing various pollutants, their applications on real wastewater, costs and considerations on their reuse after adsorption processes, has been discussed. Finally, in order to better highlights the affinity of sorbents for more pollutants (dyes, heavy metals, biorecalcitrant compounds, nitrogen and phosphate compounds), simple methodological tools such as “adsorbents-pollutants” matrices have been proposed and applied. In this manner, the adsorbent candidates for replacing commercial activated carbons have been identified.
Display omitted
•More than 170 peer-reviewed articles have been investigated.•Low-cost sorbents are divided into 6 several groups such as agricultural and industrial.•Sorbents characteristics and their adsorption capacities have been systematically collected.•Using adsorbents-pollutants matrices is possible to identify the less selective sorbents.•Results showed the need to standardize the outputs of each adsorption study.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In efforts to achieve a sustainable development goal, the utilization of CO2 to generate renewable fuels is promising, as it is a sustainable technology that provides affordable and clean energy. To ...realize the production of renewable green fuels, a proficient and low-cost technology is required. Using photo/thermal catalytic process, the goal of sustainable CO2 hydrogenation can be achieved. There have been several types of catalysts under exploration, however, they are expensive with limited availability. In the current development, green materials such as mineral clays are emerging as cocatalyst/supports for CO2 hydrogenation. Clays are bestowed with various beneficial properties such as a large surface area, high porosity, abundant basic sites, excellent thermal stability and chemical corrosion resistance. Clays are promising materials that can drastically reduce the cost in catalyst preparation, partially fulfil the energy demand and reduce greenhouse gas emission. This review aims to focus on the various types of clays and their applications in the field of photo/thermal CO2 hydrogenation to renewable fuels. Firstly, the classifications of clays are provided, whereby they can be differentiated based on their silicate layers, namely 1:1 and 2:1 type clay and their properties are thoroughly discussed to provide advantages and applications. The applications of various clays such as kaolinite, halloysite, montmorillonite, attapulgite, saponite and volkonskoite for CO2 hydrogenation reactions are systematically discoursed. In addition, various approaches to improve the capability of raw clays as catalyst support are critically discussed, which include thermal treatment, exfoliation, acid-leaching and pillaring approaches. A critical discussion regarding the engineering aspects to further enhance clay-based catalyst for CO2 hydrogenation are further disclosed. In short, clays are freely available materials that can be found in abundance. However, there are many more different types of natural green clays that have not been studied and explored in various energy applications.
Display omitted
•Mineral clays can be effectively classified based on their silicate layer.•Clays own a number of properties, making them suitable catalyst support.•Admirable CO2 conversion to fuels is attained over clay-based catalysts.•Clays can be pre-treated via various methods to enhance their properties.•Several engineering aspects further boost activity of clay-based catalysts.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Despite the tremendous improvements in conventional desalination technologies, its wide use is still limited due primarily to high energy requirements which are currently met with expensive fossil ...fuels. The use of alternative energy sources is essential to meet the growing demand for water desalination. In the last few decades a lot of effort has being directed in the use of different renewable energy (RE) sources to run desalination processes. However, the expansion of these efforts towards larger scale plants is hampered by several techno-economic challenges. Several medium-scale RE-driven desalination plants have been installed worldwide. Nevertheless, most of these plants are connected to the electrical grid to assure a continuous energy supply for stable operation. Furthermore, RE is mostly used to produce electric power which can be used to run desalination systems. This review paper focuses on an integrated approach in using RE-driven with an emphasis on solar and geothermal desalination technologies. Innovative and sustainable desalination processes which are suitable for integrated RE systems are presented. An assessment of the benefits of these technologies and their limitations are also discussed.
•This paper focuses mainly on solar and geothermal energy-driven integrated systems.•An innovative hybrid approach combining solar–geothermal has also been explored.•Matching integrated desalination processes with RE technologies are highlighted.•Innovative integrated RE-driven desalination systems are presented.•Market potential, environmental concerns and socio-economic developments are discussed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Agricultural solid wastes either in natural or in modified forms have been successfully used for decades as non-conventional cost-effective adsorbents for removing metal ions and dyes from their ...aqueous phase and have been recognized as a sustainable solution for wastewater treatment. Therefore, this review article provides extensive literature information about heavy metals and dyes, their classifications and toxicity, various treatment methods with emphasis on adsorption characteristics by numerous agricultural solid wastes, or agricultural solid waste-derived adsorbents under various physicochemical process conditions. This review article not only provided an up-to-date information on the application of sustainable low-cost alternative adsorbents such as agricultural solid wastes, agricultural by-products, and biomass-based cost-effective activated carbon and various other natural materials in the batch adsorptive removal of heavy metal and dye from aqueous phase but also presented a comprehensive compilation of adsorptive pollutant removal information based on various reported continuous column operation studies which is one of the new aspect to this review article. The effectiveness of various batch and column operational process parameters on mechanistic adsorptive removal of both heavy metals and dyes by various agricultural solid waste-based adsorbents has been critically discussed here. Batch and column adsorption mechanism, batch kinetics, column dynamic modeling, and adsorptive behavior of adsorbents under various process parameters have also been critically analyzed and compared. Finally, literature information on recovery and regeneration through desorption techniques and cost comparison of various agricultural solid waste adsorbents with commercial activated carbons have also been reported here. Conclusions have been drawn from the literature reviewed, and few suggestions for future research direction are proposed.
Since the Paris Agreement, European member countries have been committed to mitigating climate change and adapting to its effects. Climate action planning allows cities to organize their approach. It ...is critical to ensure that investments in infrastructure and services have a low-carbon impact and consider likely climate change perspectives. The output of this process is the climate action plan (CAP): one or more documents where a city sets out its roadmap to reduce greenhouse gas emissions and strengthen climate resilience throughout the community. Many cities have already developed and published a Paris Agreement-compatible CAP. The quality and compliance of these plans will also influence the achievement of the goals of the United Nations Framework Convention on Climate Change (UNFCCC, 2015). Thus, cities are crucial players in global climate change mitigation and adaptation efforts, and how they engage in climate policy is currently under debate. The paper is intended to support technological design, selecting good practices from the latest and most complete ones for climate mitigation and adaptation in urban settings. In particular, the paper focuses on public space and built environment regeneration actions that can tangibly contribute to the global climate resilience movement. Considering the operational difficulty that could arise in planning climate adaptation measures in historical urban contexts, the study critically analyzes current strategies in sedimented landscape realities of high cultural-historical value. The goal is to draw from them a cognitive and expeditious method of intervention that can be reiterated for similar contexts and is compatible with the consistency and value of urban and built heritage. The theme is timely and falls into Sustainable Development Goals No. 11 (sustainable cities and communities) and No. 13 (climate action).
•The paper analyses the most recent studies and scientific papers on climate action plans.•Good practices for climate mitigation and adaptation in urban settings are critically investigated.•The study analyses current strategies in sedimented landscape realities of high historical and cultural value.•A toolkit is proposed that can be repurposed for similar contexts.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Recent works on self-charging power technologies mainly focused on the low energy harvesting component, while its integration with the energy storage system was usually not further evaluated or ...discussed. This was addressed in the present work by providing a comprehensive state-of-the-art review on different types of energy storage used for self-sufficient or self-sustainable power units to meet the power demands of low power devices such as wearable devices, wireless sensor networks, portable electronics, and LED lights within the range of 4.8 mW–13 W. The paper presents the relevant scientific studies and recent developments on incorporating low energy harvesting with energy storage and power management systems. Recent advances on seven types of low energy harvesting technologies or transducers and eight types of micro/small-scale energy storage systems from farads to amps were examined to assess the integrated design's overall efficiency. The study focused on the design, distribution management networks, efficiency, compatibility with other components, costs, and environmental impact of self-sustainable power unit. To effectively assess the most suitable energy storage for the self-charging power unit, assessing its technical characteristics, economical, and environmental impact is discussed. Finally, the review identified the challenges and further research that must be carried out to achieve a more sustainable and stable integrated technology, moving from the proof of concept or laboratory to actual applications.
•There is a lack of literature evaluating both/combined low energy harvesting and storage.•Recent advances on seven types of low energy harvesting technologies were examined.•Eight types of micro/small-scale energy storage systems for energy harvesting were examined.•Assessment of integrated design of low power energy harvesting, energy storage, and power management.•Techno-economic analysis, environmental impacts of low energy storage were discussed.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Biobased biodegradable polymers (BBP) derived from different renewable resources are commonly considered as attractive alternative to petroleum-based polymers, such as polyethylene (PE), ...polypropylene (PP), polyethylene terephthalate (PET), etc. It is because they can address the issues of serious environmental problems resulted from accumulation of plastic wastes. In the review current methods of obtaining of most abundant BBP, polylactic acid (PLA) and polyhydroxybutyrate (PHB), have been studied with an emphasis on the toxicity of compounds used for their production and additives improving consumer characteristics of PLA and PHB based market products. Substantial part of additives was the same used for traditional polymers. Analysis of the data on the response of different organisms and plants on exposure to these materials and their degradation products confirmed the doubts about real safety of BBP. Studies of safer additives are scarce and are of vital importance. Meanwhile, technologies of recycling of traditional petroleum-based polymers were shown to be well-developed, which cannot be said about PLA or PHB based polymers, and their blends with petroleum-based polymers. Therefore, development of more environmentally friendly components and sustainable technologies of production are necessary before following market expansion of biobased biodegradable products.
Display omitted
•Technologies of PLA, PHB production have been analyzed.•Additives in fossil-based plastics and in industrially produced PLA and PHB samples are the same.•Faster degradation of PLA and PHB promotes their discharge into environment.•High toxicity and carcinogenicity of PLA, PHB and their degradation products was revealed.•Attempts of recycling of biodegradable polymers were mostly ineffective.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Rapid progress in the field of ionic liquids in recent decades led to the development of many outstanding energy‐conversion processes, catalytic systems, synthetic procedures, and important practical ...applications. Task‐specific optimization emerged as a sharpening stone for the fine‐tuning of structure of ionic liquids, which resulted in unprecedented efficiency at the molecular level. Ionic‐liquid systems showed promising opportunities in the development of green and sustainable technologies; however, the chemical nature of ionic liquids is not intrinsically green. Many ionic liquids were found to be toxic or even highly toxic towards cells and living organisms. In this Review, we show that biological activity and cytotoxicity of ionic liquids dramatically depend on the nature of a biological system. An ionic liquid may be not toxic for particular cells or organisms, but may demonstrate high toxicity towards another target present in the environment. Thus, a careful selection of biological activity data is a must for the correct assessment of chemical technologies involving ionic liquids. In addition to the direct biological activity (immediate response), several indirect effects and aftereffects are of primary importance. The following principal factors were revealed to modulate toxicity of ionic liquids: i) length of an alkyl chain in the cation; ii) degree of functionalization in the side chain of the cation; iii) anion nature; iv) cation nature; and v) mutual influence of anion and cation.
Eco to be or not to be: Principal factors modulating the biological activity of ionic liquids (ILs) and dependence of bioactivity on the nature of a biological system are summarized. Green and sustainable technologies based on ILs should include bioactivity data as the necessary task‐specific optimization parameters. Not only the direct immediate response of biological systems to ILs, but also several indirect effects and aftereffects of ILs on these systems are of primary importance.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Environmental pollution brought on by xenobiotics and other related recalcitrant compounds have recently been identified as a major risk to both human health and the natural environment. Due to their ...toxicity and non-biodegradability, a wide range of pollutants, such as heavy metals, polychlorinated biphenyls, plastics, and various agrochemicals are present in the environment. Bioremediation is an effective cleaning technique for removing toxic waste from polluted environments that is gaining popularity. Various microorganisms, including aerobes and anaerobes, are used in bioremediation to treat contaminated sites. Microorganisms play a major role in bioremediation, given that it is a process in which hazardous wastes and pollutants are eliminated, degraded, detoxified, and immobilized. Pollutants are degraded and converted to less toxic forms, which is a primary goal of bioremediation. Ex situ or in situ bioremediation can be used, depending on a variety of factors, such as cost, pollutant types, and concentration. As a result, a suitable bioremediation method has been chosen. This review focuses on the most recent developments in bioremediation techniques, how microorganisms break down different pollutants, and what the future holds for bioremediation in order to reduce the amount of pollution in the world.
PDF
