Environmental Application Of Nanotechnology Research Articles

Environmental Applications of Nanotechnology: Nano-enabled Remediation Processes in Water, Soil and Air Treatment

Environmental remediation is a research field transformed over the past two decades by the integration of engineered nanoscale materials. The market for nanotechnology in environmental applications is rapidly growing, signifying the importance of such advancements in practice as well as research. Most nano-enabled remediation challenges in water, soil and air treatment are addressed by two primary phenomena—contaminant degradation by reduction/oxidation reactions or contaminant sequestration through adsorption processes. Despite the scientific accessibility of these fields by virtue of their shared treatment mechanisms, the unique engineering and physical challenges associated with implementation require field-specific solutions and create research bubbles where scientists and engineers may be unfamiliar with current research in parallel areas. Consequently, this review is focused on summarizing the key nano-enabled technologies and their mechanisms in the fields of water, soil and air treatment, as well as describing recent advances and highlighting areas with clear direction for further development. This review covers nano-enabled processes including photocatalysis in air and water treatment, nZVI-mediated reduction and adsorption processes in soil and water treatment, and CO2 capture and reduction including the state-of-the-art materials driving research focused on improving these technologies. This review is intended as a platform for researchers to understand how their expertise fits into the larger community of remediation technology as well as to provide direction for literature review of parallel fields suiting their interest. We conclude by identifying core research focuses and underdeveloped research directions in each of the three areas, most notably, a need for guided evaluation of meaningful composite materials for next-generation catalysts.

Magnetic Fe3O4 nanoparticles enhance cyanobactericidal effect of allelopathic p-hydroxybenzoic acid on Microcystis aeruginosa by enhancing hydroxyl radical production

Recently, considerable progress has been made in the environmental application of nanotechnology. However, little is known about how nanomaterials might affect the cyanobacterial suppression potential of allelochemicals. In this study, a microcosm was employed to simulate and verify the effect of magnetic Fe3O4 nanoparticles (MFN) on the inhibitory influence of allelopathic hydroxybenzoic acid (p-Ha) on bloom-forming Microcystis aeruginosa. MFN had a hormetic effect on cyanobacterial growth. At a neutral concentration of 182 mg/L, MFN enhanced the algal suppression by p-Ha and decreased the IC50 by half, which was significantly and positively associated with the amount of OH. Furthermore, adding MFN induced a stronger physiological response than treatment with only p-Ha. The cellular integrity was severely disrupted for the cyanobacterium M. aeruginosa. The total protein content decreased rapidly to inactivate the algae by limiting the amounts of extracellular microcystin and polysaccharide released. The modification of the effect of p-Ha by MFN was reflected by the intracellular NO content of M. aeruginosa. In addition, the typical radical scavengers ascorbic acid and 5,5-dimethyl-1-pyrroline N-oxide decreased OH production to weaken algal suppression under the combined treatment with p-Ha and MFN. By contrast, the addition of Fe3+ and increasing the light intensity triggered the generation of OH and strong cyanobacterial suppression. Thus, MFN could enhance the cyanobacterial control efficiency of p-Ha and decrease the input of allelochemicals in the field. These findings suggest a novel mode of allelochemical modification by nanomaterials as a promising cyanobactericide for harmful algal bloom management.

Environmental application of nanotechnology: air, soil, and water.

Global deterioration of water, soil, and atmosphere by the release of toxic chemicals from the ongoing anthropogenic activities is becoming a serious problem throughout the world. This poses numerous issues relevant to ecosystem and human health that intensify the application challenges of conventional treatment technologies. Therefore, this review sheds the light on the recent progresses in nanotechnology and its vital role to encompass the imperative demand to monitor and treat the emerging hazardous wastes with lower cost, less energy, as well as higher efficiency. Essentially, the key aspects of this account are to briefly outline the advantages of nanotechnology over conventional treatment technologies and to relevantly highlight the treatment applications of some nanomaterials (e.g., carbon-based nanoparticles, antibacterial nanoparticles, and metal oxide nanoparticles) in the following environments: (1) air (treatment of greenhouse gases, volatile organic compounds, and bioaerosols via adsorption, photocatalytic degradation, thermal decomposition, and air filtration processes), (2) soil (application of nanomaterials as amendment agents for phytoremediation processes and utilization of stabilizers to enhance their performance), and (3) water (removal of organic pollutants, heavy metals, pathogens through adsorption, membrane processes, photocatalysis, and disinfection processes).