Titanium Dioxide: Properties, Applications, and Safety
Oxygen Sensors
Even in slightly reducing atmospheres, Titania tends to lose oxygen and become sub-stoichiometric. Thus, the material becomes a semiconductor, and the electrical resistance of the material can be correlated with the oxygen content of the atmosphere to which it is exposed.
Antimicrobial Coatings
The photocatalytic activity of titanium results in thin layers of material exhibiting self-cleaning and disinfecting properties under exposure to UV radiation. These properties make the material a candidate for applications such as medical devices, food preparation surfaces, air conditioning filters, and other medical devices and surfaces.
Titanium in the Environment
In nature, titanium is the ninth most abundant element in Earth’s crust (0.63% by mass) and is present in most igneous rocks and sediments derived from them. Important titanium minerals are rutile, brookite, anatase, ilmenite, and titanite.
Environmental Effects of Titanium
Low toxicity. In powdered metallic form, titanium metal poses a significant fire hazard and, when heated in air, an explosion hazard.
Health Effects
There is a detectable amount of titanium in the human body, and it has been estimated that we take in about 0.8 mg/day, but most of it passes through without being absorbed. It is not a poisonous metal, and the human body can tolerate titanium in large doses.
Titanium and Toxicity
Elemental titanium and titanium dioxide are of low toxicity. Due to the biocompatibility of titanium, undiscovered cases of toxicity in both elemental titanium and titanium dioxide are rare. Some important effects of titanium powder can cause tightness in the chest, pain, and breathing difficulties.
Decontamination
Researchers are working on ways to use titanium dioxide properties to benefit the environment. Research suggests that titanium dioxide can be useful in other applications to remove organic water pollutants.
Titanium Dioxide
It is used in advanced oxidation processes as a photocatalyst. The titanium oxide is TiO2. It occurs in nature in several ways:
- rutile (tetragonal)
- anatase (tetragonal)
- brookite (orthorhombic structure)
Industry and Titanium Dioxide
Rutile titanium oxide and anatase titanium oxide are produced industrially in large amounts and used as pigments, catalysts, and in the production of ceramics.
Properties
Titanium oxide properties:
One of the chemicals is whiter: it reflects almost all the visible radiation that reaches it and keeps the color permanently. Despite their relative abundance in nature, its natural composition is never pure, and it is mixed with contaminant metals such as iron, aluminum, and radioactive elements.
Applications
Titanium oxide has also been used as a bleaching agent and opaque porcelain glazes.
- It is also a potent photocatalyst that can break down almost any organic compound.
- Titanium oxide pigments are mainly used in the production of paints and plastics.
- In medicine, titanium is used for hip and knee prostheses, pacemakers, bone plates and screws, and plates for skull fractures. It has also been used to set false teeth.
Production
Titanium oxide is the most important white pigment produced in the world.
The main users are the paint and plastics industries. For every ton of manufactured titanium oxide, there are nearly 3.8 tons of byproducts. These byproducts are used as raw materials in applications such as water treatment, prefabricated gypsum, and agriculture.
This compound is also a precursor material for the production of titanium metal.
Health and Safety
Titanium dioxide powder for inhalation has recently been classified by the International Agency for Research on Cancer (IARC) as carcinogenic for humans. This can cause tightness and pain in the chest, coughing, and difficulty breathing. Contact with skin or eyes may cause irritation.
Photocatalysis
Titania acts as a photosensitizer for photovoltaic cells, and when used as an electrode coating, titanium dioxide has potential for use in energy production as a photocatalyst.