Environmental Remediation of Desalination Plant Outfall Brine Discharge from Heavy Metals and Salinity Using Halloysite Nanoclay

Synthesis and characterization of Pd(0) Schiff base complex supported on halloysite nanoclay as a reusable catalyst for treating wastewater contaminants in aqueous media

Naturally available tubular Halloysite nanoclay is modified with platinum for the fabrication of autonomous self‐moving nanojets. The nanojets exhibit great performance in the removal of heavy metal ions in aqueous solutions. The heavy metal ions get readily adsorbed onto the large surface area available on the Halloysite nanoclay. The fabricated nanojets are observed to have a greater efficiency with sensing of larger sized metal ions (Hg2+ and Pb2+) as compared to smaller sized ions (Zn2+ and Cd2+), and especially sensitive toward the “detection” of mercury ions. The proposed system displays a wide detection range (0.25–1000 ppb). Moreover, the system displays high sensitivity with low limit of detection (3.24 ppb) achieved, which falls in the permissible range for mercury in drinking water (2–5.5 ppb) as set by the World Health Organisation. The self‐moving nanojets serve as mobile nanosensors for the simultaneous detection and removal of heavy metals in aqueous samples.

Utilisation of cement brick waste as low cost adsorbent for the adsorptive removal of copper, nickel and iron from aqueous solution: Batch and column studies

Influence of singular and binary nanomaterials on the physical, mechanical and durability properties of mortars subjected to elevated temperatures and freeze–thaw cycles

Design of highly robust halloysite nanoclay supported palladium complex as a highly active heterogeneous catalyst for construction of biaryls

The valorization of agricultural by‐products into sustainable packaging materials is one of the best strategies to utilize industrial waste efficiently. In this study, defatted pumpkin seed meal (DPSM) has been converted into films by impregnating selected concentrations of halloysite (HS) nanoclay (1%, 2% and 3% w/w). Various analytical techniques, including scanning electron microscopy (SEM), X‐ray diffraction (XRD), differential scanning calorimetry (DSC) and barrier property measurements, were employed to characterize the developed films. The appearance of the roughness on the surface of the films was evident from SEM micrographs upon the addition of HS. No change in the crystallinity of DPSM occurred when HS was incorporated; however, the Tg showed a variation with the loading concentration of the clay. Fourier transform infrared spectroscopy (FTIR) spectroscopy indicated that the decrease in hydrogen bonding was associated with increasing the HS concentrations. The addition of HS improved the tensile strength, stress relaxation percentage and Young's modulus, while the elongation at break was reduced at a similar condition. The biodegradability of the film was excellent within 20 days of the burying period. Overall, the developed films could be a potential candidate for sustainable food packaging.

A one‐pot biosynthesis of an aerogel composite based on attapulgite clay/bacterial cellulose to remove Pb²⁺ ion

In recent years, the development of environmentally friendly materials obtained from renewable resources has attracted immense interest due to the new sustainable development policies. Cellulose is a readily available, naturally occurring biodegradable, and biocompatible linear polysaccharide. Recently, room temperature ionic liquids have been used as solvents to produce regenerated cellulose (RC) due to their attractive properties such as good chemical and thermal stability, low flammability, low melting point, and ease of recycling. Polymer/nanofiller nanocomposites are believed to have strong potential to widen polymer applications due to enhanced performance. It is also widely accepted that the incorporation of small amount of nanofiller (less than 5 wt%) into bio-based matrixes to produce nano-biocomposite materials with enhanced mechanical, permeability, and thermal properties. The tubular silica-based naturally occurring nanofiller, halloysite nanotubes (HNT), has been investigated due to its high surface area, unique geometry, and its potential to make the hydrogen bonding with polymers to disperse well in the matrix. Graphene nanoplatelets (GNP) have also attracted enormous attention among polymer engineers over the last few years due to its unique electrical, thermal, and mechanical properties. Single layer two-dimensional GNP sheet is considered as the strongest material along with the high surface area and aspect ratio. The chapter aims to highlight the effect of the addition of two different types of nanofillers such as HNT and GNP to produce RC nanocomposites on selected properties.

Self‐propelled, autonomous micro and nanomachines are at the forefront of current nanotechnology. These micro and nanodevices move actively to perform desired tasks, usually using chemical energy from their surrounding environment. Typically, these structures are fabricated via clean room or template‐based electrodeposition methodologies, which yield relatively low numbers of these devices. To utilize these machines in industrial‐scale operations, one would need an inexpensive fabrication route for mass production of nanomachines. The use of naturally occurring nanotubes, Halloysite nanoclay, to fabricate functional nanomotors in great quantities is demonstrated. These nanotubes can be mined in ton quantities and used as base for the fabrication of nanomachines. In addition, it is well known that the surface groups of Halloysite nanoclay bind strongly with heavy metals, which makes it potentially useful in environmental remediation.

Sustainable solutions for desalination plant outfall brine: Modified halloysite nanoclay-based remediation of heavy metals and salinity

A new carbonaceous adsorbent for heavy metal removal from aqueous solution prepared from paper sludge by sulfur-impregnation and pyrolysis

Heavy metal ions adsorption from dairy industrial wastewater using activated carbon from milk bush kernel shell

A DNA-inorganic hybrid film (DNA film) was prepared by mixing DNA and a silane coupling reagent, bis(trimethoxysilylpropyl)amine. This DNA film can accumulate heavy metal ions in aqueous solution. We have demonstrated the accumulation of rare earth metal and heavy metal ions using DNA-inorganic hybrid-immobilized glass beads (DNA beads), which were prepared by coating the DNA-inorganic hybrid onto glass beads. When these DNA beads were placed in an aqueous solution of metal ions and incubated for 24 h (batch method), the DNA beads selectively accumulated heavy metal and rare earth metal ions. The maximum-accumulated amounts of Cu2+, Cd2+, In3+ and La3+ were ∼1.2, 0.94, 1.6 and 1.3 μmol, respectively, for 1 mg of DNA (3.0 μmol of nucleotide). The molar ratio of DNA to a metal ion was nucleotide:metal ion=1:0.5. Finally, we demonstrated the accumulation of metal ions by a DNA-bead column (DNA column). As a result, the DNA column effectively accumulated the heavy metal and rare earth metal ions. The DNA column was recycled by washing with an EDTA solution. DNA-immobilized glass beads (DNA beads) were prepared by coating DNA-inorganic hybrid material onto glass beads. When these DNA beads were placed in an aqueous metal ion-containing solution and incubated (batch method), the DNA beads selectively accumulated the heavy and rare-metal ions, such as Cu2+, Cd2+, In3+ or La3+. Therefore, we demonstrated the accumulation of metal ions by a DNA-immobilized glass bead column (DNA column). As a result, the DNA column effectively accumulated the heavy and rare-metal ions. Furthermore, the DNA column could be recycled by washing it with an aqueous EDTA solution.

Copper and nickel ion removal from synthesized process water using BSA-coated bubbles

Chapter 16 - Current development in poly(vinyl alcohol) nanocomposites for heavy metal ions removal