28 April 2021

Bio-nanocomposites as nanoengineered wastewater treatment

By Ir. Ts. Dr Kuok King Kuok & Ts. Dr Hj Muhammad Khusairy bin Bakri

Our natural environment offers enough opportunities for the sustainability of humanity and our planet, especially in providing safe and clean air. Forest and water are the most valuable form of nature commodities available to humans, which exist well before the evolution of life.

But as time passes, humans tend to be ignorant and are careless with the environment due to corruptions, directly contributing to pollution problems everywhere. Despite the fact that water has long been one of the most important natural resources, access to clean drinking water has become a significant global challenge in the twenty-first century where its usage and importance should not be overlooked.

“Alle Dinge sind Gift, und nichts ist ohne Gift, allein die Dosis macht dass ein Ding kein Gift ist.” which means, “All things are poison, and nothing is without poison, the dosage alone makes it so a thing is not a poison”.Paracelsus

Small portion of impurities in water may cause serious health issues to humans. This principle was supported by Paracelsus, who implies that even if water and oxygen are not properly mixed, it can be toxic if consumed in high quantity particularly dirty and unfiltered water. The toxicity of any chemical depends on many factors, including the extent to which it enters an individual’s body.

Water makes up around 70% of the Earth’s atmosphere. According to a World Health Organization (WHO) fact sheet and other sources, around 97% of water on Earth is salt water, while the remaining 3% is freshwater. Of this, 70% consist of frozen freshwater in polar ice caps and glaciers, and the rest is either present as surface moisture or remain in deep aquifers.

Overall, fresh water that is available for user accounts for only 1% or 0.007% of the total water on the planet which is a very small amount. This highlights the need and importance of continuous conservation, treatment, and research in obtaining fresh water that can be consumed by the human race in daily life.

In Malaysia, especially Sarawak, water quality is declining due to many factors such as urbanisation, population development, agricultural activity, climate change, and other related factors. The irresponsible release of organic and inorganic chemicals resulting from rapid industrialisation and urbanisation has a negative impact on the quality of natural resources for example, water contamination.

A variety of chemicals can contaminate freshwater including potentially poisonous elements, dyes, phenolic compounds, pesticides, herbicides, pharmaceuticals, personal care goods, and many others. These toxins have the potential to be bio-accumulative, persistent, carcinogenic, mutagenic, and harmful to marine species, flora and fauna, as well as human health.

Scientists face significant challenges because water pollution poses an ever-increasing danger to human health and the atmosphere. Removing toxins from water has become a must. For water purification, a variety of techniques are used including precipitation, coagulation, flocculation, incineration, ion exchange, reverse osmosis, membrane filtration, electrochemistry, photo electrochemistry, advanced oxidation processes (AOPs), adsorption, and biological methods.

It is crucial to extract harmful pollutants from wastewater to a safe level, while still doing so quickly, safely, and at a fair rate. With the highly advanced nanotechnology, especially in bio-nanocomposites and nano-engineered wastewater treatments, it could potentially play a significant role in wastewater treatment.

Nanotechnology is the science of manipulating matter at the nanoscale (1–100 nm). It can develop new bio-nanomaterials for the nanoengineered wastewater treatment of radioactive materials especially on the surface water, air, and wastewater. Nanocomposites, especially biopolymer nanocomposites, have gotten a lot of attention out of all the engineered nanostructured materials.

For water remediation, biopolymer nanocomposites outperform ordinary nanoparticles (NPs) in terms of adsorption capability, selectivity, and stability. It is also cheap and easily disposable which could reduce pollution problem. The methods of solution mixing, melt blending, layer-by-layer deposition, in-situ polymerization, electro polymerization, and surface-initiated polymerization have all been used to create biopolymer nanocomposites. Biopolymer nanocomposites are also being used to remove toxins from water in a variety of ways.

The COVID-19 pandemic, Industrial Revolution 4.0, and digital economy era have taught us to be more independent, and make use of the existing and available information and data while conserving the environment at the same time. Therefore, strong collaborative support from government, industries and communities is needed to drive this initiative, especially to develop new bio-nanotechnology for nanoengineered wastewater treatment. This could enhance the production of drinking water for human consumption particularly those in rural areas who have limited access to fresh water.

Ir. Ts. Dr Kuok King Kuok is a senior lecturer and Ts. Dr Hj. Muhammad Khusairy bin Bakri is an alumnus from Swinburne University of Technology Sarawak Campus. They can be reached via email at kkuok@swinburne.edu.my / mbakri@swinburne.edu.my.