Canadian Wollastonite
Research
Canadian Wollastonite (CW) has been involved in many studies exploring the various uses for CW’s products. Wollastonite itself is a very uncommon mineral and the lack of widespread and large-scale use has hindered demand to explore its properties and potential industrial applications.
Studies on the effects of wollastonite in agricultural, chemical, and civil applications have added to the interest in the product as it becomes better known.
In order to expand the list of potential uses and customers, CW has multiple ongoing research projects underway, some being co-funded with grants from the Natural Sciences and Engineering Research Council (NSERC).
This white mineral for a green world has a proven track record in the scientific literature to clean our soils, waterways, and atmosphere.
Metals Remediation
Industrial minerals, with or without modification, are useful for removing and sequestering harmful waste products.
The use of industrial minerals in environmental remediation is likely to grow with the growth of legislation, especially during the presidency of Barak Obama. The minerals most likely to be affected by such trends will be limestone, lime, magnesium hydrate, micas, clays, zeolites, activated carbon, graphite, wollastonite, diopside and synthetic silicas.
Carbon Sequestration
Plants, crops and trees naturally absorb atmospheric carbon dioxide (CO2) during photosynthesis and then pump surplus carbon through their roots into the earth around them. In most soils, this carbon can escape back to the atmosphere or enters groundwater.Knowing this, a team from Newcastle University aims to design soils that can remove carbon from the atmosphere, permanently and cost-effectively using soils containing calcium-bearing silicates.Calcium silicates are minerals that occur naturally in many different rocks and also in artificial materials such as concrete. (Wollastonite is a pure calcium silicate)The team believe the carbon that oozes out of a plant’s roots may react with the calcium to form the harmless mineral calcium carbonate(1). The carbon then stays securely locked in the calcium carbonate, which simply remains in the soil, close to the plant’s roots, in the form of a coating on pebbles or as grains.
Wollastonite is a versatile and unique white mineral with proven benefits across a wide range of plant types and environments. The combination of a readily available supply of calcium and silicon can account for the positive effects of wollastonite in a wide range of soil based research studies.
Horticultural Crops
Pumpkin growers looking for new cultural practices to improve production and fruit quality while reducing input cost may benefit from findings of research conducted at the Rutgers University, New Jersey Agricultural Experiment Station.
One of our experiments compared the influence of different types of liming materials to neutralize soil acidity and improve pumpkin plant health. Regular agricultural limestone, chemically referred to as calcium carbonate, was compared with calcium silicate in a field with an initial soil pH of 5.9. Calcium silicate is an alternative liming material that supplies the nutrient silicon in a plant available form. Silicon is now recognized as a quasi-essential nutrient with beneficial effects on disease suppression and stress tolerance on several crops.
Field Crops & Grasses
Groundbreaking Research Demonstrates Benefits on a Variety of Crops. According to Heckman, field trials using calcium silicate indicate that enhanced levels of silicon uptake can provide additional crop benefits beyond its use as a liming material. While powdery mildew disease in pumpkin fruit and wheat grain was suppressed, in some years Heckman found that yields were also increased on the plots in which calcium silicate was added.
Wollastonite has proven useful in a wide range of industrial applications with a composition that is low in carbon and high in of silicon and calcium.
Influence Of Wollastonite On Mechanical Properties Of Concrete
Abstract: Studies were made on cement concrete and cement-fly ash concrete mixes incorporating wollastonite as partial substitute of cementitious material and sand respectively. Improvements in compressive (28-35%) and flexural strength (36-42%) at 28 and 56 days respectively were observed by incorporation of wollastonite (10%) in concrete mixes. By incorporation of wollastonite, reduction in water absorption, drying-shrinkage and abrasion loss of concrete, and enhancement in durability against alternate freezing-thawing and sulphate attack were observed. Because of high concrete strength and abrasion resistance, a better utilization of concrete cross section is possible. Alternatively, thickness of pavement slab can be reduced by incorporation of wollastonite micro-fibres in concrete mixes.
Refractory Applications
Wollastonite – calcium metasilicate with the CaSiO3 composition – is now a basic material for aluminum casting equipment in western countries. It is associated with the combination of the following characteristics of wollastonite:
- it is not moistened with aluminum;
- it is inert to aluminum;
- it has low thermal conductivity;
- it is nontoxic.
These ceramic materials offer promise as the thermoprotective materials for lining thermal units with operating temperatures up to 1000oC. The tests of the specimens from composite ceramic materials with silica fibers revealed practically limitless heat resistance of the specimens under cyclic heating, nonwettability with aluminum melt, lack of cracks under repeated immersion in aluminium melt.
Medical Applications
Preliminary in vitro experiments revealed that wollastonite (CaSiO3) is a potentially highly bioactive material that forms a hyroxyapatite (HA) surface layer on exposure to simulated body fluid with an ion concentration, pH and temperature virtually identical with those of human blood plasma. The formation of the HA layer is an essential requirement for an artificial material to be used as bioactive bone substitute. This finding opens up a wide field for biomedical applications of wollastonite. Biomaterials used as implants in the human body require strict control of trace elements and of the toxic species specified in American Society for Testing and Materials F-1185-88 (As, Cd, Hg and Pb) in ceramic hydroxyapatite for surgical implantation. In this work, two types of pseudowollastonite, the high temperature form of wollastonite, were analysed by using cold vapour atomic absorption spectrometry and hydride generation atomic absorption spectrometry, in order to determine the elements stated in the above-mentioned norm, and inductively coupled plasma atomic emission spectrometry to establish the SiO2/CaO ratio of the two materials and analyse for all other impurities introduced by the raw materials and by the processes of synthesis, sintering and grinding. Barium and Mg were especially prominent in raw materials, and Zr, Y, Mg, W, Co and Ni come mainly from the processing.
Nanofibre Applications
The effect of impregnation with wollastonite nanofibers, a nontoxic mineral material, on the biological durability of poplar wood (Populus nigra) against a white-rot fungus (Trametes versicolor) was studied. Wollastonite nano-suspension with a concentration of 6.3% was used; the size range of the nano-wollastonite (NW) was 30 to 110 nm. Results showed that decay exposed for 16 weeks in accordance with the standard DIN-52176 specifications resulted in a 47.5% mass loss in control specimens, while in the NW-impregnated specimens, only 3.6% mass loss occurred. Mechanical tests on separate sets of specimens impregnated with NW without exposure to the decay organism showed no significant difference in the mechanical properties. Thus, it can be concluded that impregnating poplar wood with NW as a preservative significantly increases the biological durability of poplar wood against deterioration by Trametes versicolor. Furthermore, it does not have negative effects on the mechanical properties in the impregnated poplar specimens.
Source: https://www.canadianwollastonite.com/research/
Magazine
No information