Optimising the effectiveness of osmotic desalination process by using graphene-based nanomaterials

Graphene can be found in pure form or as derivatives of graphene; both forms are known as graphene-based nanoparticles (GNPs). These derivatives of graphene include graphene oxide (GO), reduced GO, GNP–polymer nanocomposites, and GNP–metal hybrids. These modifications of graphene nanoparticles can lead to nanomaterials or nanocomposites with different and novel properties, such as antimicrobial, adsorbent, and catalytic properties. As antimicrobials, GNPs can be used in environmental and medical applications. In environmental application, as an antimicrobial, the particles of GNPs have shown to inactivate both pure cultures and wastewater microbial communities. When using the GNPs as coatings in medical devices or water treatment membranes, the surface inhibits microbial survival and biofilm growth. Aside from antimicrobial applications, GNPs have also been used as adsorbent; owing to their large surface area and presence of functional groups. These GNPs have the ability to remove both heavy metals and organic contaminants from water. In addition, GNPs can serve as semiconductors to increase the efficiencies of photocatalytic and electrocatalytic systems, which can be used to inactivate microorganisms and degrade organic chemicals in water. The many uses and applications of GNPs will inevitably lead to their way to the environment through manufacturing byproducts and wastes, as well as weathering of commercial products containing GNP-based nanomaterials. GNPs are bioactive and they can impact the environment. While GNPs might be extremely useful, we should find a middle ground between toxicity and applications to minimize risks to the ecosystem.

برای بررسی اثر سطوح شوری آب آبیاری و زمان شروع آبیاری با آب شور و لب‌شور بر خصوصیات کمی خربزه دیررس، آزمایشی با 7 تیمار و 3 تکرار در قالب بلوک‌های کامل تصادفی با استفاده از روش آبیاری قطره‌ای نواری، در مرکز تحقیقات کشاورزی و منابع طبیعی خراسان رضوی انجام شد. تیمارهای آبیاری عبارت بودند از: 1- آبیاری با آب شیرین (6/0 دسی‌زیمنس بر متر) از ابتدای کاشت تا انتهای فصل برداشت، 2- آبیاری با آب با شوری 3 دسی‌زیمنس برمتر از ابتدا تا انتهای فصل داشت، 3-آبیاری با آب با شوری 6 دسی‌زیمنس بر متر از ابتدا تا انتهای فصل، 4- آبیاری با آب با شوری 6 دسی‌زیمنس بر متر از 20 روز بعد از جوانه‌زنی تا انتها، 5- آبیاری با آب با شوری 3 دسی‌زیمنس بر متر از 20 روز بعد از جوانه‌زنی تا انتها، 6- آبیاری با آب با شوری 6 دسی‌زیمنس بر متر از 40 روز بعد از جوانه‌زنی تا انتها و 7- آبیاری با آب با شوری 3 دسی زیمنس بر متر از 40 روز بعد از جوانه‌زنی تا انتهای فصل داشت. نتایج نشان داد که، شوری آب بر عملکرد کل، عملکرد اقتصادی و کارآیی مصرف آب آبیاری تاثیر معنی‌داری داشت. بالاترین عملکرد کل و عملکرد اقتصادی و کارآیی مصرف آب آبیاری از تیمار شاهد بدست آمد که تفاوت آن‌ها با تیمارهای آب شور و لب‌شور معنی‌دار بود. در ضمن تفاوت بین عملکردهای تیمارهای شور و لب‌شور معنی‌دار نبودند. آبیاری با آب شیرین در اوایل دوره رشد باعث افزایش محصول نشده بلکه، باعث وارد شدن تنش بیشتر به گیاه می‌شود.

The UN World Water Development Report 2016, <i>Water and Jobs</i>: A Critical Review

Treatment of nontraditional source waters (e.g., produced water, municipal and industrial wastewaters, agricultural runoff) offers exciting opportunities to expand water and energy resources via water reuse and resource recovery. While conventional polymer membranes perform water/ion separations well, they do not provide solute-specific separation, a key component for these treatment opportunities. Herein, we discuss the selectivity limitations plaguing all conventional membranes, which include poor removal of small, neutral solutes and insufficient discrimination between ions of the same valence. Moreover, we present synthetic approaches for solute-tailored selectivity including the incorporation of single-digit nanopores and solute-selective ligands into membranes. Recent progress in these areas highlights the need for fundamental studies to rationally design membranes with selective moieties achieving desired separations.

Due to their unique physicochemical properties, graphene-based nanoparticles (GPNs) constitute one of the most promising types of nanomaterials used in biomedical research. GPNs have been used as polymeric conduits for nerve regeneration and carriers for targeted drug delivery and in the treatment of cancer via photothermal therapy. Moreover, they have been used as tracers to study the distribution of bioactive compounds used in healthcare. Due to their extensive use, GPN released into the environment would probably pose a threat to living organisms and ultimately to human health. Their accumulation in the aquatic environment creates problems to aquatic habitats as well as to food chains. Until now the potential toxic effects of GPN are not properly understood. Despite agglomeration and long persistence in the environment, GPNs are able to cross the cellular barriers successfully, entered into the cells, and are able to interact with almost all the cellular sites including the plasma membrane, cytoplasmic organelles, and nucleus. Their interaction with DNA creates more potential threats to both the genome and epigenome. In this brief review, we focused on fish, mainly zebrafish (Danio rerio), as a potential target animal of GPN toxicity in the aquatic ecosystem.

Rising agricultural water scarcity in China is driven by expansion of irrigated cropland in water scarce regions

Water scarcity and pollution pose significant challenges to global environmental sustainability and public health. As these concerns intensify, the quest for innovative and efficient water treatment technologies becomes paramount. In recent years, graphene-based nanomaterials have emerged as frontrunners in this pursuit, showcasing exceptional properties that hold immense promise for addressing water contamination issues. Graphene, a single layer of carbon atoms arranged in a hexagonal lattice, exhibits extraordinary mechanical, electrical, and chemical properties. These inherent characteristics have led to a surge of interest in leveraging graphene derivatives, such as graphene oxide (GO), reduced graphene oxide and functionalized graphene, for water treatment applications. The ability of graphene-based nanomaterials to adsorb, catalyze, and photocatalyze contaminants makes them highly versatile in addressing diverse pollutants present in water sources. This review will delve into the synthesis methods employed for graphene-based nanomaterials and explore the structural modifications and functionalization strategies implemented to increase their pollutant removal performance in water treatment. By offering a critical analysis of existing literature and highlighting recent innovations, it will guide future research toward the rational design and optimization of graphene-based nanomaterials for water decontamination. The exploration of interdisciplinary approaches and cutting-edge technologies underscores the evolving landscape of graphene-based water treatment, fostering a path toward sustainable and scalable solutions. Overall, the authors believe that this review will serve as a valuable resource for researchers, engineers, and policymakers working toward sustainable and effective solutions for water purification.

Chapter 9 - Graphene-based nanomaterials in cancer treatment and diagnosis

The advent of engineered nanomaterials and architectures hold promise of an unprecedented performance in removing persistent chemicals and recovering resources from water. Nanostructured electrodes can be designed to entail a large specific surface area and tunable properties, which allow tailoring of the electrocatalytic surface to enhance the reactions with specific contaminants. In the scope of the European Research Council (ERC) Starting Grant project ELECTRON4WATER, we developed graphene- and metal-based nanostructured electrodes for electrochemical water treatment and resource recovery. We developed graphene sponge electrodes capable of degrading highly persistent pollutants such as per- and polyfluoroalkyl substances (PFAS), as well as other organic and microbial pollutants. This is achieved while overcoming a major bottleneck of electrochemical water treatment – formation of toxic chlorinated byproducts, as graphene sponge anode does not form any chlorate and perchlorate even in the presence of high chloride concentrations (&gt;1 g/L), and displays very low current efficiency (i.e., &lt;0.1%) for the generation of chlorine. The estimated cost of their bottom-up synthesis is two orders of magnitude lower compared with the commercial electrodes. First scalable graphene-enabled electrochemical systems were developed within an ERC Proof of Concept Grant GRAPHEC and will be further upscaled and commercialized within a European Innovation Council (EIC) Grant FOREVER WATER. Furthermore, our group is currently developing functionalized monolith electrodes for electrochemical recovery of lithium and other critical raw materials (CRMs) from industrial waste streams, in the scope of ERC Consolidator Grant ELECTROmonoLITH. Through different technologies and projects developed in our group, this presentation will illustrate the significance of nanotechnology in the development of high-performing, cost-effective, and environmentally friendly water treatment and resource recovery technologies.

A framework for the design of the future energy-efficient, cost-effective, reliable, resilient, and sustainable full-scale wastewater treatment plants

The magnitude of the spread of the water hyacinth ( Eichhornia crassipes ) makes its extermination, either by physical or chemical methods, a costly and painstaking process. The exercise has to be repeated annually for an indefinite period, a burden that poorer nations are hardly equipped to support. The alternative is to find a use for this plant so that its eradication would entail some financial returns. A variety of studies have been carried out in this direction. The manifold uses to which the plant has been put include principally: (i) a fertilizer, compost and mulch; (ii) fodder; (iii) a raw material for industry; (iv) a protein source and source for carotene and other chemicals; (v) a pollution control agent; and (vi) biomass for biogas production. This paper represents a review of the past work on eradication and utilization of water hyacinth relevant in water treatment and resource recovery in the field of environmental engineering with special reference to India.

Chapter 16 - Antimicrobial activity of graphene-based nanomaterials: Current development and challenges

Graphene-based nanoparticles are widely applied in many technology and science sectors, raising concerns about potential health risks. Emerging evidence suggests that graphene-based nanomaterials may interact with microorganisms, both pathogens and commensal bacteria, that dwell in the gut. This review aims to demonstrate the current state of knowledge on the interplay between graphene nanomaterials and the gut microbiome. In this study, we briefly overview nanomaterials, their usage and the characteristics of graphene-based nanoparticles. We present and discuss experimental data from in vitro studies, screening tests on small animals and rodent experiments related to exposure and the effects of graphene nanoparticles on gut microbiota. With this in mind, we highlight the reported crosstalk between graphene nanostructures, the gut microbial community and the host immune system in order to shed light on the perspective to bear on the biological interactions. The studies show that graphene-based material exposure is dosage and time-dependent, and different derivatives present various effects on host bacteria cells. Moreover, the route of graphene exposure might influence a shift in the gut microbiota composition, including the alteration of functions and diversity and abundance of specific phyla or genera. However, the mechanism of graphene-based nanomaterials' influence on gut microbiota is poorly understood. Accordingly, this review emphasises the importance of studies needed to establish the most desirable synthesis methods, types of derivatives, properties, and safety aspects mainly related to the routes of exposure and dosages of graphene-based nanomaterials.

Due to the unique chemical and physical properties, graphene-based nanomaterials are increasingly being introduced into various scientific fields. They all play very important roles in different fields and are widely used. Graphene oxide (GO) is one of the most popular and representative carbon nanomaterials; scientists have great research interest in it. When carbon nanomaterials such as GO are released into the aquatic environment, their physicochemical properties will be influenced by natural light, resulting in the potential change in toxic effects on aquatic organisms. Algae, as a typical aquatic organism, is extensively regarded as a model microorganism to assess the biotoxicity of nanomaterials. In this review, we overview the light-mediated impact of GO on algae. We summarize the photo-transformation of GO under different illumination conditions and the effect of illumination on the physicochemical properties of GO. Then, we combined metabolomics, genotoxicity, and proteomics with standard toxicity assays (cell division, membrane permeability, oxidative stress, photosynthesis, cellular ultrastructure, and so on) to compare native and environmentally transformed GO induction toxicological mechanisms. By correlating lights, physicochemical properties, and biotoxicity, this review is valuable for environmental fate assessments on graphene-based nanoparticles, providing a theoretical basis and support for evaluating the potential ecological health and environmental risks of graphene-based nanoparticles in real natural water environments.

Chapter 2 - Energy and resources recovery from wastewater treatment systems