Tiles from eggshells?
SIX scientists, Rassimi Abdul Ghani, Mohd Hanafiah Abidin, Ahmad Zafir Romli, Mohd Hariz Kamarudin, Zaleha Afandi and Muhamad Faizal Abd Halim of the Institute of Science, are turning one of the world’s oldest waste into useful flooring materials. They made tiles from eggshells.
Naming the tiles EPoSTi, they made composite tiles by combining polymers and chicken eggshells, an innovation from domestic waste. Explaining their work in an expo, the use of eggshells in micro size will increase the rigidity and stiffness of the composite, making it a suitable flooring material. This is due to the nature of eggshells which is good as rigid particulate fillers for tiles. The combination offers excellent impact resistance, as it is able to withstand a strong force. In short, it is durable.
EPoSTi is also suitable for underwater flooring. Durable when tested in labs, they were found to be stable when subject to thermal testing. The eggshells by nature can withstand temperatures of up to 750 oC, thus it passed the thermal testing easily. This feature guarantees safety against high temperature-making it practical in hot climate countries.
Another benefit of EPoSTi is that it is suitable for any decorating purposes, designed according to one’s taste. Fulfilling almost all specifications for flooring materials, it offers another choice of decor at a cheaper price. Another thing, inventing tiles from eggshells, otherwise seen as waste, can reduce headaches of clogged drains, waste treatment, odour emission, thus cleaner environment have we.
Rassimi explained further that eggshell is a by-product which contains about 94% of calcium carbonate by weight, which is easily obtained due to heavy consumption of egg in food industry. For example, China, the world number one egg producer, has boosted her output 67.8% over the past decades, thus a rich source of potential natural filler for EpoSTi. This is good news for tiles industry.
Information Contacts:
Rassimi Abdul Ghani
Mohd Hanafiah Abidin
Ahmad Zafir Romli
Mohd Hariz Kamarudin
Zaleha Afandi
Muhamad Faizal Abd Halim
Institute of Science
UiTM Shah Alam
ahamd349@salam.uitm.edu.my
Glass fiber goes green
CHANGING social and economic trends increase pressure on the forest products industry to produce green products. It is especially more pressing as we are in the midst of scarcity of resources but having to respond to our ever-changing needs. Thus Suriana Rofie of the Faculty of Applied Sciences, UiTM Shah Alam, went green. She compared the properties of glass fiber which was reinforced with polyester composites from oil palm empty fruit bunch (EFB). Suriana named her product Hybrid EFB Fiber with Glass Fiber Reinforced Polyester Composites (Hybrid Composites).
In her experiment, the main raw materials were the empty fruit bunches of oil palm, Elaesis guineensis, which was built into a mat. The EFB mat fiber was overlaid with glass fiber, placed both on top and bottom faces of the mat. The resin adhesive used was a mixture of polyester and 3% of methyl ethyl ketone peroxide (MEKP). The resinated mat was cold pressed for about one hour to consolidate. The hybrid then was tested with three different ratios of EFB and Polyester - 20:80, 30:70 and 40:60 and its physical properties were evaluated in the form of water absorption and thickness swelling. Whilst mechanical properties were tested on static bending, tensile and impact, according to the ASTM D790-ISO 178, ASTM D638-ISO 527 and ASTM D6110-02-ISO 180 standards.
Suriana found that the samples made from EFB and Polyester at a ratio of 30:70 attained the highest values among all mechanical properties tests. At the same time the physical properties, specimens of EFB and Polyester 20:80 ratio were more dimensionally stable. Here we may have discovered that EFB is suitable as a new raw material for Hybrid Natural Fiber Composite manufacturing.
For these manufacturers, this is good news as glass fiber can be another means to overcome the shortage of solid wood other than to reduce the price of raw materials. Suggested for future research, Suriana said that one could also experiment on wood polymer composites, natural fiber reinforced composites or other bio-based materials.
Information Contacts:
Suriana Rofie
Faculty of Applied Sciences
UiTM Shah Alam
suriana @salam.uitm.edu.my
Rubber leaves to the rescue
SOME would remember, in the wilderness of the rubber trees, we walked to school. Running under the trees, we enjoyed the popping sound of their fruits, pulled the hardened latex and picked the dry leaves to make our dolls and dry flowers.
Thanks to the British, in 1876, rubber was planted in Singapore, then Malaya. This was the first time it was planted outside Brazil and in the 60’s rubber turned out to be our main source of economy. We were once the world’s number one rubber and its downstream products exporter. Then, almost every part of a rubber tree is useful except its leaves. But 50 years later, Megat Ahmad Kamal Megat Hanafiah of UiTM Pahang, discovered the use of its leaves.
Megat found that its dry leaves, are not only for making dolls and dry flowers, but also useful for treating chemical waste, thus earning him the USM Best PhD award in 2009. His thesis reported that the dry rubber leaves are able to eliminate copper and nickel ions from wastewater. In his study, the dry leaves were turned to powder, which he exclusively called a HeveaMET biosorbent. Megat will have a field day producing his HeveaMET as Malaysia has more than 1.2 million hectares of land planted with rubber trees.
In the experiment, the dry leaves were chemically modified with NaOH, then worked to remove Cu(II) and Ni(II) ions from wastewater. The presence of heavy metals in the environment is of major concern because of their toxicity, bioaccumulation, and threat to human life and environment. Removing heavy metals from our environment, especially wastewater, is shifted from using electrolysis, chemical precipitation, electroflotation, oxidation-reduction, solvent extraction and ion-exchange to using biosorbents.
In recent years, many low cost biosorbents obtained from lignocellulosic agricultural by-products have been investigated for their biosorption capacity towards heavy metals. Agricultural wastes are now becoming viable alternatives since they are abundant, much cheaper and have various functional groups such as carboxylic acid, ester, carboxylate, hydroxyl, phenolic and amino. They can act as adsorption sites for heavy metal ions.
Every year, mature rubber leaves will fall in January to March, producing a huge amount of solid waste. Turning this plant waste into biosorbent offers a cost effective and a green way to treat metal-laden wastewater.
In Megat’s work, the data obtained from column experiment indicated that 10 g of HeveaMET was able to remove 7.1 and 11.1 L of Cu(II) and Ni(II) ions at 10 mg/L concentration, respectively. HeveaMET was able to be regenerated using 0.1 M HCl or HNO3 and reused in three cycles. The main mechanisms involved in heavy metals removal were ion-exchange, complexation and physical adsorption.
Information contact:
Megat Ahmad Kamal Megat Hanafiah
Faculty of Applied Sciences
UiTM Pahang
makmh@pahang.uitm.edu.my
Inhibiting corrosion
TO prevent corrosion, it needs a strong bonding between the corrosion preventive layer and the metal surface. Thus our researchers are developing a Shiff base polymer, a new organic thin layer material with stronger metal interaction to prevent corrosion. Shiff base compounds are a type of soft base compound that contains C = N (imine). It would bind strongly to soft or intermediate acids metals such as iron, copper or nickel.
More detailed, in this study, Yong Soon Kong and colleagues will synthesize and characterize the Schiff based polymer which will be derived from cystamine and glutaraldehyde. Then the study plans to absorb the polymer onto metal substrates and to characterize the polymeric layer. Lastly, the study will determine the corrosion efficiency through weight loss method and Electrochemical Impedance Spectroscopy.
The study is planned in three stages: synthesizing and characterizing the Shiff based polymer, completing the coating and characterization of the metal surface and studying the corrosion on the metal surface.
Firstly, the target Schiff base compounds will be synthesized from a condensation of cystamine and glutaraldehyde via a series of mixed polar and non-polar solvents. This is to find a suitable ratio of the optimum yield of the polymer. The Shiff base polymer is expected to be non-soluble in water in a form of white to yellowish powder or oils which will be dried with silica contained desiccators.
Secondly, the physical and chemical characterizations will be conducted that involved the following 4 steps:
a. Melting point
b. Elemental analysis for C, H, N, S, O.
c. Fourier transform infrared spectroscopy
d. Nuclear magnetic resonance spectroscopy
Then the corrosion inhibition properties of the Schiff base polymer will be studied in an electrochemical analysis, an electrochemical Impedance Spectroscopy (EIS). The EIS is conducted by coating a thin layer of this Schiff base polymer onto a polished metal sheet (1.0 cm x 1.0 cm x 0.06 cm). The sheet then will be immersed into a non-deaerated dichloromethane solution of Schiff base polymer ranging from 10-2 to 10-5 moIL-1 for 48 hours. While immersed, the complexation of the characterized Schiff base polymer with metal will take place on their surface. The coated sheet then will be collected and dried. Then it will be sent for anti-corrosive testing. Here, the elemental chemical state of ligands to metal will be characterized by the X-Ray Photoelectron.
It is seen that the best possible use of this sulfur and nitrogen bearing coatings is in paints and lubricants, where having it will enable the paint to enhance resistance against corrosion.
Information Contacts:
Yong Soon Kong
Hadariah Bahron
Mohamad Kamal Harun
International Education Centre (INTEC)
Section 17 Campus
UiTM Shah Alam
yongsk@salam.uitm.edu.my
Watering only when they are thirsty
EXOTIC in full bloom, spectacular in colours, they never fail to enthral us, offering luxury in galleries and romance in weddings. Orchid, a prehistoric plant, are known for its beauty and loveliness. They are the most diverse flowering plants on earth, with more than 20,000 known species. Hybrids are increasing, offering more splendour and grandeur to our homes.
Scientifically, orchids are divided into sympodial and monopodial, hugely popular around the world as lovely ornamental plants. Majorities of them are an epiphyte. So exquisite, orchid has turned into an industry, of which Malaysia is one of the main exporters. Malaysia exports potted, flasked seedlings and cut orchids. To improve the orchid industry, scientists see that its watering system must be automated.
Although having earned a mere 11 million ringgit in 2000, orchids have gained footing in the Malaysian Agrigultural Policy 1992 – 2010. Malaysian scientists and farmers see that, to earn more revenue, orchids must be taken care tenderly and watered precisely. Over watering can taint healthy growth and quality blooms of the orchids, exposing them to infection, increasing operation cost, worse, killing them altogether.
At present, orchid farmers schedule their watering manually or by automatic timers. But Mohd Khairi Nordin and Shah Rizam Mohd Shah Baki think that, other than experience, it needs science to water orchids. They think that before watering, the plants need to be ‘asked’ whether they need water. Farmers reported they do not know the exact time to water their orchids thus they do it daily in the morning. Daily watering increases cost of water and electricity that makes about half of their total operation cost.
To know the exact time orchids need water, Mohd Khairi and Shah Rizam will detect the orchids’ stem diameter to know its water content. The stem of an orchid, called ‘pseudobulb’, stores water thus detecting the stem’s water content will inform its needs for water in real time. Analyzing several other parameters from other data, the critical stem diameter (CSD) will be determined to set a trigger point to the watering system. So, the plant will be watered only when they ‘ask’ for water. With additional variables study in plant’s microclimate, further intelligent watering system can be developed.
Some recent work on stem diameter has focused only on terrestrial (soil) plant, such as lemon, pepper, plum, apple, cotton and grapevine to develope a precise irrigation schedule. There are also other methods to develope precise irrigation or watering schedule, such as detecting the plant canopy temperature and using airborne or satellite images.
Detecting a plant stem diameter was first studied in 1975 by several researchers. The idea was that plants contain thousands cell called xylem. The cell functions are to transport water and nutrients that the xylem cells exclusively react to the water content in plant. Thus the idea in measurement stem diameter on terrestrial plant could enrich our beloved orchids in the 21st century.
Thanks to the ‘xylem’ and our scientists, our orchid farmers will be enjoying watering their orchids only when the orchids get thirsty.
Information Contacts:
Mohd Khairi Nordin
Shah Rizam Mohd Shah Baki
Faculty of Electrical Engineering
UiTM Shah Alam
mkhai974@salam.uitm.edu.my
sharizam@salam.uitm.edu.my
The other side of a purple flower
ROSE is a rose writes Stein, like a dandelion dancing in the wind says an idiom. So pleasing flowers are to our eyes, not only they are the charm of our adoration and romance, loveliness and happiness, they are also the subject of our paintings, source of medicine, and ingredients of food. About one thousand years ago, after the fall of the Roman Empire, early Muslim chemists, Jabir Ibnu Khayyan, Al-Kindi and Al- Razzi discovered ‘distillation’, leading to extraction of oil from flowers. And recently, researchers Ruziyati Tajuddin, Siti Marsinah Tumin, Kamariah Muda and Suzaini Abdul Ghani of the Faculty of Applied Sciences, UiTM Shah Alam, discovered a cheaper method to extract colours from flowers.
Ruziyati Tajuddin and colleagues created a special home-built extractor, superheated water extraction (SWE), to extract the rich purple and pure white colours of the ‘senduduk’ flowers, Melastoma malabathricum, a type of wildflowers easily found in the Malaysian bushes and roadsides.
Unlike the Medieaval Muslim scholars, who distilled rose and lavender petals for the rich’s luxury life, Ruziyati and her research team created an eco-friendly colour extractor for those suffering from chemical sensitivities when wearing chemically dyed fabrics. To them, the extracted colours can be fabrics natural dye. Natural dye extraction comes handy in the wake of the wide use of chemical dye in fabric industry. Metals are often deployed as dye fixatives, and sometimes directly applied in the dyeing, such as dioxin, chrome, copper and zinc, and formaldehyde.
According to Ruziyati, SWE is simple and cheap. Eco-friendly, as no harmful organic solvent is used, it extracts colours from flowers using superheated water. In their experiment, the senduduk flower petals were placed in an extraction cell in an oven. Water as a solvent, then, was flowed through a capillary tube into the extraction cell at a desired elevated temperature to begin the extraction. The process of extraction took 5-10 minutes. After that, the heated extracted colourant from the petals was cooled in a water-bath before it was collected in a collection bottle, ready as a dye.
SWE is economical as only a small amount of petals is required, e.g. to dye a square meter of silk, only 16.1 gram of flower petals in 1.5 liter of water are needed. In contrast, a traditional boiling method requires 1 – 1.5 kg of flower petals with more than 1.5 liter of water to dye a square meter of silk. Secondly, different shades of colour can be obtained by SWE easily at selected temperatures.
Senduduk is native to Malaysia and always blooming. Other than that, the commercial value of senduduk is still untapped. This 2 m tall senduduk plants is seen with disdain, many a time called a weed. It grows wild in abandoned clearings and waste ground. If left uncleared it swells into thickets. But if its wild-growing nature were tapped in an organised farm, the farming could have been run effortlessly to provide an abundant source of natural dye.
Ruziyati suggested that other than flowers, SWE can also extract colours from turmeric, onion skin, fruits and leaves. The research team further suggested that these natural dyes are most suitable for baby clothings as their skin is delicate and sensitive. They named the product dyed with these natural dyes as GCTex
(Green Chemistry Textile product). Following, GCTex won gold awards in three expositions: IID 2008 UITM; ITEX 2008, Kuala Lumpur; and IENA 2008, Germany.
As Ruziyati and team extracted the purple of the senduduk, other than Jabir Ibnu Khayyan, Al-Kindi and Al-Razzi proud of their distillation made to other use, Renoir, Monet and Vincent Van Gogh would be glad - the flowers are now a paint to paint flowers on canvas.
Information Contacts:
Ruziyati Tajuddin
Siti Marsinah Tumin
Kamariah Muda
Suzaini Abdul Ghani
Faculty of Applied Sciences
UiTM Shah Alam
ruziy039@salam.utim.edu.my
Allure of pineapple
LANKY models strutting in cotton, linen, chiffon, or silk, making statement in beautiful creations - why not make statement with alluring dresses from pineapples?
Often we heard mothers reminiscing their hard times during the Japanese occupation when they had to sew with threads from pineapple leaves. If so, we can spin yarn from pineapple leaves threads then. After all, we have been relying on plants for clothings – the cotton. Now Malaysian scientists are looking into the potential of another ‘cotton’; the pineapple. Our Asean neighbour, the Philippines, has been creative with pineapple leaves fiber long time ago. They already have pineapple fabrics.
Jamil Salleh and his research team study is timely as we have scores of pineapple plantations with tonnes of leaves burnt away. There has not been much interest in pineapple fibres in our country. Hence, he is optimist that the abundant pineapple fibres in
Malaysia, if extracted, can be marketed as ‘exotic’ textile. A good news for fashion designers Zang Toi or Bernard Chandran? For them it could be a work of mix and match for yet another charming creations.
Jamil and colleagues will experiment on the long fine fibres by scrapping and retting the leaves. It is a preliminary study to assess the best technique to extract the fibres from the leaves.
Scrapping is a traditional method where the epidermal tissue of the leaves is scrapped from the surface and back of the leaves using broken plate or coconut shell to expose the fibres. The method is still used in the Philippines today. It is tedious, time consuming and labor intensive. As much as 500 leaves can be scrapped in a day by an expert scrapper. After scrapping, the fibres will be washed thoroughly with water and then air-dried.
Apart from scrapping, the fibre can also be extracted by retting. Retting is the use of micro organism and moisture to dissolve or rot away the epidermal tissue and pectine of the leaves, which will separate the fibre from the leaves. There are many types of water retting such as still water, running water and dew and rain retting. These methods are slow and consumes time, and hence less popular. However, around 2.5 - 3.5% of fibres can be recovered from both methods.
Other than that, Jamil and his fellow researchers are looking into chemical retting under alkaline condition and microbes as they have been used to extract other fibres such as flax and kenaf. It was found that fibers produced from microbe retting are with higher residual gum content and lower elongation but better tenacity and softness. As a comparison, chemical retting produces lower tenacity and thicker fibres while water retting produces weak and low quality fibres.
In the study, the fibres will be extracted from pineapple leaves by both scrapping and retting methods. In the scraping method, porcelain scrap will be used to remove the epidermal tissue of the leaves. For retting, four methods will be employed which are immersion in water for certain duration, use of NaOH/ acetic acid and EDTA, use of enzyme (xylanase/ pectinase/cellulase), and combination of chemical and enzyme retting. Other mechanical extraction methods using special fabricated equipment will also be experimented.
The strength of the extracted fibres will be evaluated using tests of linear density, tenacity, microscopic appearance, micronaire and fibre strength. Then, the fibres will be hand-spun into yarn or dref spinning. The spun yarn then will be tested for its physical properties such as linear density (count), single strength, yarn appearance and hairiness. A comparison fibre and yarn properties with regards to the extraction techniques employed will be evaluated to determine the best fibre extraction technique.
Information Contacts:
Jamil Salleh
Wan Yunus Wan Ahmad
Mohd Rozi Ahmad
Mohd. Iqbal Misnon
Department of Textile Technology
Faculty of Applied Sciences
UiTM Shah Alam
jamilsal@salam.uitm.edu.my
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