Chemical and Materials Engineering

Kanuka is an indigenous New Zealand plant that has gained attention due to the presence of bioactive compounds. All parts of this plant such as leaves were not left out in traditional medicinal usage as observed from literature. It has also been found to possess strong anti-inflammatory properties. Extraction of these compounds responsible for the biological activities in this plant is needed to make it readily available for use in food, medical, cosmetic and nutraceutical industries.

Project Aims: The main objective of this project is to use subcritical and supercritical fluid extraction techniques to extract lipids, and flavonoid and phenolic compounds from the leaves of Kanuka.

Requirements: The student would have independent working style and able to work under the lab health and safety regulations. In addition, the student must be able to work in the process and analysis laboratories. The student should be self-motivated and hardworking.

Background:
Composting process is so important not only as an acceptable method for solid waste treatment but also highly qualified compost can be used as a soil amendment. One of the key uncertainties about using the compost as fertiliser is determined by the evaluation of the heavy metals elements in soil. Many experts believe that even using the compost just for several years may not show any changes in chemical properties of the soil but in long-term, the accumulated heavy metals can pass the redline. Humic and Fulvic acids are the two main products of the compost that can be extracted from the matured compost. In addition to many benefits of these products, by extracting process it will be possible to eliminate the heavy metals.

Project Aims: The main objective of this project is to extract humic and fulvic acids from a matured compost using a series of solvent extractions and to optimise the extraction process.

Requirements: The student would have independent working style and able to work under the lab health and safety regulations. In addition, the student must be able to work in the process and analysis laboratories. The student should be self-motivated and hardworking.

Background:
Volatile anaesthetics, such as sevoflurane and desflurane, are commonly used for pain management in hospitals. The volatile anaesthetics are minimally metabolised in patient’s lungs, where most of them are scavenged and released unabated to the atmosphere. These agents are potent greenhouse gases. The magnitude of the carbon footprint from the Middlemore Hospital in Auckland, New Zealand alone is in the order thousands of tonnes carbon dioxide equivalent annually. This is equivalent to the carbon footprint of 500 round-trip flights to London from Auckland.
Adsorptive separation is the most extensively investigated processes. Activated carbons, zeolites and metal-organic frameworks, are promising solid adsorbents that are reported to be able to capture the volatile anaesthetics. Among the adsorbents, activated carbons are the most commonly used. Whilst activated carbons are affordable, widely available in the commercial market, and generally safe to operators, the adsorption is non-specific. For enhanced adsorption of volatile anaesthetics, the surface of activated carbons can be modified to improve both their chemical and physical characteristics.
Project Aims: The main objective of this project is to evaluate the effect of various surface modifications on activated carbons to enhance the adsorptivity of volatile anaesthetics.
Requirements: The student would have independent working style and able to work under the lab health and safety regulations. In addition, the student must be able to work in the process and analysis laboratories. The student should be self-motivated and hardworking.

In comparison to the traditional incandescent and fluorescent lighting sources, white LEDs have remarkable advantages that they have much longer lifetime, higher luminous efficiency, and lower energy consumption etc. Phosphors from a single inorganic host (such as a silicate) will be synthesized, then the photoluminescence properties will be assessed.

This project aims to synthesise a phosphor with a full emission wavelength range (upon UV excitation) for white LED application. The student will mainly use XRD technique for phase structure analysis, and a fluorescence spectroscopy for measuring photoluminescence properties.

A student with phase analysis skills or knowledge on X-ray crystallography is desired. A suite of advanced instrument will be used in this research. This is an excellent training opportunity for student’s final year research project.

Oxygen storage materials (OSMs) are those materials with unique ability to reversibly absorb and release oxygen. YBaCo4O7+δ is one of the most interesting OSMs which demonstrates high oxygen absorption capability at low-temperature range (ca. 200-400°C). It has been investigated for several applications including automotive exhaust treatment, solid-oxide fuel cells, and oxygen separation membranes. However, the major problem hindering its practical application is its thermal instability at a certain temperature range (ca. 600-900°C).

This project aims to synthesise YBaCo4O7-based materials with improved thermal stability while maintaining their oxygen storage capacity via solid state synthesis. The effect of substitution strategies will be studied. Thermogravimetric analysis (TGA) will be used to assess the thermal stability and oxygen storage capacity. Besides, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) will be carried out to determine the phase structure and valence state of transition metal elements after the redox reactions.

Microencapsulation is used to contain materials such as drug, food, and many organic and inorganic products. It is usually done using suspension polymerisation to produce capsules ranging from nano to micron in size. We have already published a number of papers and one patent on the subject, so the student could do some reading to familiarise himself/ herself with the subject.

We have two types of UV reactor to be used in the project and we have all the chemicals needed.

In any building there is a need to have air indoor exchange with fresh air to sustain healthy indoor environment. However, indoor air has high energy content (hot or cold) and that will lead to a tremendous energy being lost. We have developed a compact energy storage unit containing phase change materials (PCM), which is capable of storing the heat available in the exhausted air to be recovered by the entering fresh air in a reverse cycle. The unit was carefully designed and tested and require some design modification to be more efficient. The work is confidential so it was not published but I have a full report, which would give the student full understanding of the topic. Good knowledge in heat transfer is required.

Homogenisation is a well-known processing used to process milk and other food products. However, this project is not about homogenisation but rather aiming to develop a reduced temperature sterilisation technology. The aim is to lower existing sterilisation temperature such as that used in the processing of UHT milk. There are evidence that the combination of high pressure homogenisation with mild heat could inactivate spores, leading to a sterilised product. The student should have some background in microbiology.

A materials research project with strong application prospects.
Using electrochemical processing techniques, including electroplating, electroless deposition, anodization and their combination, to make micro-nano-composite coatings with improved hardness, wear/corrosion resistance, controlled colour, wettability, antifouling and antimicrobial properties for a wide range of industrial applications.

Studies of transition metal semiconducting oxides, including ZnO, TiO2, WO3 and V2O5, in the forms of thin films and/or porous structures, and their properties and applications for solar energy harvest, microwave adsorption, high efficient light emission, and Raman spectroscopy enhancement.

Environmental cleaning technologies including wastewater treatment and removal of air pollutants are a very important area. Our work is to develop innovative oxide photo-catalysts, noble metal doped semiconducting oxides, and combination of catalysts with membranes; and to study their properties including selective absorption, decomposition of organic pollutants and valuable materials recovery.

Bulk density is an important powder property in industry, for storage, shipping and final product quality. However, it is not always clear how to achieve the desired bulk density. The aim of this project is to understand the effect of morphology on bulk density of different powders. Light microscopy will be used with image processing to characterise the morphology of different powders and investigate how it affects packing behaviour.

In our lung modelling group, we develop computational models of the pulmonary system. We are developing a model to help in the application of radiation therapy (RT) for patients with lung cancer. In this project, we are working with a dataset of around 100 patients with lung cancer before and after RT. We are developing statistical analysis techniques to understand this data. In this summer project we are looking for a student who is interested in statistical analysis and modelling and a passion for improving healthcare. The work will require analysis of patient datasets – using image processing and statistical analysis software - and revolve around validating a statistical shape model describing the shape of patient lungs.

It would be useful if the student had some familiarity with the Python programming language – or at the least an interest to learn this programming language.

What problems does it solve?:
In New Zealand, and no doubt many countries of the world, the ability to exclude water from a structure is a major problem. It is responsible for many millions of dollars in damage.
We are not aware of any product that achieves the combination of properties that the proposed invention achieves. Notably a very high level of water resistance.
MgO is recognized as an excellent fire proofing material and it is mandatory for a specific product to be individually certified for its fire protection capabilities. Once tested the board can be CodeMark certified for use in the fire protection of buildings. This is a highly regulated and specialized area and opens a large market that currently has limited alternatives.
MgO board is sustainable, and has low CO2 emissions compared to Fiber cement boards due to high levels of cement used in the manufacture.
Although existing MgO board achieves more than most products, it does not match the ‘water resistance/waterproof ability’
Water ingress into buildings is arguably the biggest problem to be addressed for health, safety, and structural integrity.
To be ‘waterproof’ is not the answer. Waterproof means nothing passes through. This means there is no vapour or air transfer leading to the potential for condensation build up, ideal conditions for degradation through rust, mould, oxidation, and rot. Resulting reduced air changes produce an unhealthy environment.
Water resistance, on the other hand, means to resist but not entirely prevent the penetration of water, or that water is repelled for a short time but is not waterproof.
Most building materials that are not ‘waterproof’ are hydrophilic and will hold onto water for a prolonged period. Hydrophilic materials such as fibre cement, plywood, MDF, OSB and plasterboard will absorb (> 25%) and hold on to water for prolonged periods. Thus, disrupting their properties and causing mould growth, degradation, and ultimately failure.
Our attempts will include,
Introducing waterproofing / water repellency by adopting several treatment methods and enhancing the structural properties including
a) homogeneously mixing the silane / siloxane blend, in wet stage during the processing of boards;
b) enhancing mechanical properties by introducing Sustainable Cementitious Materials (“SCMs”) to the formulation.
Gaps –
There is no effective solution to address the following issues related to poor quality construction/ prefabricated panels.
1. In NZ, ~500 lawsuits filed in against NZ companies supplying poor quality pre-fab panels – fiber cement, gypsum, aeriated concrete etc. - leaky building syndrome, mold and fungus growth - risking health and wellbeing of the residents
2. NZ government’s recent initiative to build more than 10,000 houses per annum - requires better performing, water, fire, mold and fungus resistant construction panels
3. It is not that this multi-billion $ industry that had a total value of $34 billion in 2016, with an 8% growth in the past 4 yrs. And the forecast is a further 23% growth in the next 4 yrs to $42 b in 2020

Hence, the manufacturers of pre-fabricated panels needs to pay more attention to solve these issues immediately.
We will undertake to make the improvements with the collaboration of an industry partner, MagRoc through this summer students project.