Abiotic stress in plants is a crucial issue worldwide, especially heavy-metal contaminants, salinity, and drought. These stresses may raise a lot of issues such as the generation of reactive oxygen species, membrane damage, loss of photosynthetic efficiency, etc. that could alter crop growth and developments by affecting biochemical, physiological, and molecular processes, causing a significant loss in productivity. To overcome the impact of these abiotic stressors, many strategies could be considered to support plant growth including the use of nanoparticles (NPs). However, the majority of studies have focused on understanding the toxicity of NPs on aquatic flora and fauna, and relatively less attention has been paid to the topic of the beneficial role of NPs in plants stress response, growth, and development. More scientific attention is required to understand the behavior of NPs on crops under these stress conditions. Therefore, the present work aims to comprehensively review the beneficial roles of NPs in plants under different abiotic stresses, especially heavy metals, salinity, and drought. This review provides deep insights about mechanisms of abiotic stress alleviation in plants under NP application.

Coping with the Challenges of Abiotic Stress in Plants: New Dimensions in the Field Application of Nanoparticles.

An increase in the pollutants such as hazardous refractory contaminations, organic dyes, pharmaceutical and pesticide contaminants which are widely disposed to water resources due to population and global industrialization is becoming one of the most significant health issues in the world. Due to the unique properties, easy production, low-cost preparation, and excellent degradation of water and wastewater pollutants, magnetic-MXene nanocomposites are promising candidates with many attractive characteristics. These composites offer new fascinating perspectives in various applications such as biosensors, cancer theragnostic, imaging strategies, and especially in water treatment. This paper reviews magnetic-MXene nanocomposites for removing contaminants from aqueous environments. The concept of using magnetic nanomaterials for water treatment, MXene applications and implications for the degradation of water and wastewater pollutants, and magnetic-MXene nanocomposites for water treatment will be discussed. Future trends on MXene and Magnetic-MXene nanomaterials for water treatment and environmental applications will also be explained. • Pollutants removal by magnetic-MXene-based nanocomposites was reviewed. • Magnetization of nanocomposites of MXene enhanced pollutants degradation. • Magnetization of nanocomposites of MXene enhanced antibacterial properties. • A future perspective was developed. 

Magnetic-MXene-based nanocomposites for water and wastewater treatment: A review

Cadmium (Cd) and lead (Pb) contaminations are disturbing environmental issues, which causes serious harm to aqueous systems and human health. Therefore, removing them from aqueous solution is essential to prevent its damage to the environment. Environmental adsorption research as one solution has seen a boom over the past decade. Using modified biochar has proved to be more suitable for the adsorption of cadmium and lead. Most of the studies apply a routine method such as kinetic and isotherm modelling to demonstrate the macroscopic trend of adsorption, often without elaborative evaluation of the effectiveness and characteristics of the models. This review compiles different adsorption kinetics and isotherms models and also presents their origins, modified versions, and their applicability in the liquid adsorption situation. The effect of experimental parameters and adsorption mechanisms are discussed to study the adsorption performances of modified biochar. The adsorption mechanism was majorly by surface precipitation, ion exchange, electrostatic attraction, complexation and physical adsorption. The adsorption was majorly endothermic and spontaneous. Additionally, preparation and regeneration of modified biochar are also presented to provide a direction for sustainable improvement. This paper summarizes with a note on challenges, prospects and future perspectives of adsorption of cadmium and lead pollutions.

Adsorption of cadmium and lead from aqueous solution using modified biochar: A review

Cadmium (Cd) and lead (Pb) contaminations are disturbing environmental issues, which cause serious harm to aqueous systems and human health. Therefore, removing them from aqueous solution is essential to prevent their damage to the environment. Environmental adsorption research as one solution is promising and has been getting a lot of attention in the recent years. Using modified biochar has proved to be more suitable for the adsorption of cadmium and lead. In this review, the sources of cadmium and lead in the environment and their hazards have been elucidated. In addition, the preparation methods of modified biochar to remove Cd and Pb have been discussed. This review also presents the adsorption kinetics and isotherms results for the adsorption of Cd and Pb from aqueous solution using modified biochar. The effect of experimental parameters and adsorption mechanisms are also discussed in order to understand the adsorption performances of modified biochar in great detail. The adsorption mechanisms were surface precipitation, surface complexation, ion exchange, chelation, electrostatic attraction, inner sphere complexation, redox and physical adsorption. The adsorption was mainly endothermic and spontaneous. Additionally, the results on the regeneration of modified biochar are presented to provide a direction for sustainable improvement. Finally, this review article also provides the challenges, prospects and future perspectives of adsorption of cadmium and lead from aqueous solutions using the modified biochar. 

A review on three-dimensional cellulose-based aerogels for the removal of heavy metals from water

Water pollution is one of the global challenges that society must address in the 21st century aiming to improve water quality and reduce human and ecosystem health impacts. Industrialization, climate change, and expansion of urban areas produce a variety of water pollutants. In this work, we discuss some of the most recent and relevant findings related to the release of heavy metals, the possible risks for the environment and human health, the materials and technologies available for their removal. Anthropogenic activities are identified as the main source of the increasing amounts of heavy metals found in aquatic environments. Some of the health hazards derived from repeated exposure to traces of heavy metals, including lead, cadmium, mercury, and arsenic, are outlined. We also give some perspectives about several techniques used to detect heavy metals, as well as about the factors that could affect the contaminant removal. The advantages and drawbacks of conventional and non-conventional heavy metal removal methods are critically discussed, given particular attention to those related to adsorption, nanostructured materials and plant-mediated remediation. Some of the commercial products currently used to eliminate heavy metals from water are also listed. Finally, we point out some the requirements and opportunities linked to developing efficient methods for heavy metal removal, such as the ones that exploit nanotechnologies.

Heavy metal water pollution: A fresh look about hazards, novel and conventional remediation methods

Aldehydes are commonly encountered Volatile Organic Compounds (VOCs) released to the atmosphere from a variety of anthropogenic sources. Based on the increasing interest in developing sustainable and environmentally friendly materials for the decontamination of VOCs, cellulose particles have emerged as one possible candidate, but there is a lack of understanding of the physicochemical properties affecting the adsorption of VOCs, and the effect of the extraction source on these intrinsic features. The present study was focused on the evaluation of unmodified cellulose particles extracted from biodiverse sources in Ecuador as potential VOC decontaminants. Modifications of the natural fibers with polyethylenimine (PEI) coating were performed to enhance the adsorption effectiveness. Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) measurements, and scanning electron microscopy (SEM) methods were used to characterize the physicochemical properties of the isolates. Gas chromatography assays demonstrated that unmodified cellulose can adsorb an aldehyde VOC, hexanal, reaching up to a 56.42 ± 7.30% reduction. Electrostatic coating of the cellulose particles with small quantities of PEI enhanced the VOC remediation capacities (i.e. 98.12 ± 1.18%). Results demonstrated that the biodiverse plant source of the cellulose isolate can affect the gas capturing properties, and that these particles can be an environmentally friendly solution for effective adsorption of VOC pollutants.

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Cellulose particles capture aldehyde VOC pollutants

Bryan Aldaz1, Freddy Figueroa2 and Isaac Bravo3 DOI. 10.21931/RB/2020.05.02.13 Abstract: The widespread industrialization, urbanization, and technological development have triggered the daily release of considerable amounts of pollutants, specifically in aquatic environments. Previous research and work-studies indicate the existence of defined properties, such as low cost, non-toxicity, biodegradability, reusability, and easy synthesis, preparation or extraction, which make a material an ideal agent for the remediation of water or the environment. Therefore, the scientific community has focused on the development and study of several novels, environmentally friendly, and cost-effective materials. Cellulose is the most abundant natural polymer encountered worldwide. Thereby, due to the unique biological properties that this biopolymer possesses, it has emerged as a potential candidate to replace synthetic materials for practical bioremediation of contaminated water. Furthermore, the presence of hydroxyl groups on its surface makes this biopolymer highly malleable, thus significantly enhancing its physicochemical properties by using a wide variety of functional groups and modification methods. The present review describes the different biopolymers useful for remediation of environmental pollution, explores in more detail the characteristics of cellulose and its promising applications in the decontamination of water pollution, and pays special attention to the removal of heavy metal ions, dyes, and hydrophobic organic compounds.

/pdf/cellulose-for-the-effective-decontamination-of-water-58ug5eo9g0.pdf

Freddy Figueroa

Papers

Heavy metal water pollution: A fresh look about hazards, novel and conventional remediation methods

Cellulose particles capture aldehyde VOC pollutants

Cellulose for the effective decontamination of water pollution