Application of nanotechnology in wastewater treatment

Abstract

Conventional wastewater treatment methods include various physical, chemical and biological processes. The results of such treatment can be limited because of high investment cost or, in some cases, due to poor treatment efficiency. For that reason, new approaches are continuously being developed as a means of supplementing or replacing traditional water treatment methods. The paper provides an overview of development of nanotechnology over time in the sphere of wastewater treatment, and examines the influence of nanomaterials on human health and environment, while also providing a review of future development trends in nanotechnology.

Kinetics and Nanoparticle Catalytic Enhancement of Biogas Production from Wastewater Using a Magnetized Biochemical Methane Potential (MBMP) System

“…This signifies the hydrocarbon chains were closely packed in their crystalline state, which enhanced the electrostatic force of attraction [6,13]. The broad and sharp bands at 1479 cm −1 , 1027 cm −1 and 882 cm −1 might be due to the overlaid intramolecular hydrogen bound (O-H) ascribed to the symmetric and asymmetric stretching vibrations of the CH 2 [7,13]. Notwithstanding, the absorbance intensity at 1655 cm −1 , 1593 cm −1 and 1508 cm −1 denotes the carbonyl (C=O) and alkene (C=C) stretching vibrations due to the aromatic rings of the Ms with sludge [7,13].…”

“…The FTIR spectra (Figure 3) of Ms with and without sludge had active functional groups (polymeric hydroxyl, carbonyl and aromatic rings) which were chemisorbed onto their surface. In Figure 3, the minor band at 453 cm −1 assigned may be due to the vibration of Fe-OH bonds [7,13]. Thus, the surfactant molecules in the transmission state were being subjected to surface hydroxylation and thereby shifting the bands towards the lower wavenumber region (<800 cm −1 ).…”

“…This has sparked significant interest in developing wastewater treatment technologies worldwide, owing to the rapid industrialization and environmental pollution accompanying it [1][2][3][4]. The swift utilization of nanomaterials (like coagulants, nanotubes, nanowires, metals) and generation of a huge amount of pollutants such as heavy metals in the wastewater setting cannot be excluded from this industrial evolution [5][6][7]. However, recovery of valuable products such as energy from wastewater and landfills is gaining much attention through worldwide application of the anaerobic digestion (AD) process [3,4,8].…”

“…Recent advancing technologies such as membrane filtration, ion exchange, magnetic coagulation, adsorption and advanced oxidation processes are emerging to eliminate the contaminants from the wastewater before discharging to the water bodies [4,7,10]. In response, nanotechnology has drawn the attention of many researchers for biotechnological, pharmacological and separation applications [6,10,11].…”

“…However, there is still ongoing debate about the use of aluminum and iron-based coagulants, and their safety and toxicity towards biological systems [6,20]. Thus, there is a high possibility of the accumulated nanomaterials to affect the treatability performance of the downstream process and to incur costs of landfill disposal [20,21], notwithstanding the occurrence and transportation routes (Figure 1) of emerging contaminants (nanoplastics, pharmaceuticals, antibiotics) ending up in the WWTP [7,8,16]. These undergo a series of transformations through the different unit operations from physical, chemical to biological treatment processes [4].…”