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51-523: Until early 2015, the building housed DuPont's headquarters. In December 2014, DuPont announced that it would move and consolidate its corporate headquarters at its nearby Chestnut Run Plaza site and that The Chemours Company , which spun off from DuPont in 2015, would move into the DuPont Building. As well as Chemours, the building houses The Playhouse on Rodney Square (formerly the DuPont Playhouse),

102-617: A thin film , its refractive index and colour make it an excellent reflective optical coating for dielectric mirrors ; it is also used in generating decorative thin films such as found in "mystic fire topaz". Some grades of modified titanium based pigments as used in sparkly paints, plastics, finishes and cosmetics – these are man-made pigments whose particles have two or more layers of various oxides – often titanium dioxide, iron oxide or alumina – in order to have glittering, iridescent and or pearlescent effects similar to crushed mica or guanine -based products. In addition to these effects

153-558: A "safe level for daily intake of the food additive could not be established". In 2022, the UK Food Standards Agency and Food Standards Scotland announced their disagreement with the EFSA ruling, and did not follow the EU in banning titanium dioxide as a food additive. Health Canada similarly reviewed the available evidence in 2022 and decided not to change their position on titanium dioxide as

204-446: A direct hydrometallurgical process or through the main industrial production processes, the sulfate process and the chloride process . The sulfate process represents 40% of the world’s titanium dioxide production and is protected in 23% of patent families. The chloride process is only mentioned in 8% of patent families, although it provides 60% of the worldwide industrial production of titanium dioxide. Key contributors to patents on

255-671: A diseased or physically damaged dermis could be the true cause of insufficient barrier protection. SCCS research found that when nanoparticles had certain photostable coatings (e.g., alumina , silica , cetyl phosphate, triethoxycaprylylsilane , manganese dioxide ), the photocatalytic activity was attenuated and no notable skin penetration was observed; the sunscreen in this research was applied at amounts of 10 mg/cm2 for exposure periods of 24 hours. Coating TiO 2 with alumina, silica, zircon or various polymers can minimize avobenzone degradation and enhance UV absorption by adding an additional light diffraction mechanism. TiO 2

306-526: A food coloring, it has E number E171. World production in 2014 exceeded 9 million tonnes. It has been estimated that titanium dioxide is used in two-thirds of all pigments, and pigments based on the oxide have been valued at a price of $ 13.2 billion. In all three of its main dioxides, titanium exhibits octahedral geometry , being bonded to six oxide anions. The oxides in turn are bonded to three Ti centers. The overall crystal structures of rutile and anatase are tetragonal in symmetry whereas brookite

357-506: A limited colour change is possible in certain formulations depending on how and at which angle the finished product is illuminated and the thickness of the oxide layer in the pigment particle; one or more colours appear by reflection while the other tones appear due to interference of the transparent titanium dioxide layers. In some products, the layer of titanium dioxide is grown in conjunction with iron oxide by calcination of titanium salts (sulfates, chlorates) around 800 °C One example of

408-443: A local structure in which each Ti is coordinated to, on average, about 5 oxygen atoms. This is distinct from the crystalline forms in which Ti coordinates to 6 oxygen atoms. Synthetic TiO 2 is mainly produced from the mineral ilmenite . Rutile , and anatase , naturally occurring TiO 2 , occur widely also, e.g. rutile as a 'heavy mineral' in beach sand. Leucoxene , fine-grained anatase formed by natural alteration of ilmenite,

459-536: A long time. Widely-occurring minerals and even gemstones are composed of TiO 2 . All natural titanium, comprising more than 0.5% of the Earth's crust, exists as oxides. As of 2006, titanium dioxide had been regarded as "completely nontoxic when orally administered". However, concerns persist. TiO 2 whitener in food was banned in France from 2020, due to uncertainty about safe quantities for human consumption. In 2021,

510-423: A pearlescent pigment is Iriodin, based on mica coated with titanium dioxide or iron (III) oxide. The iridescent effect in these titanium oxide particles is unlike the opaque effect obtained with usual ground titanium oxide pigment obtained by mining, in which case only a certain diameter of the particle is considered and the effect is due only to scattering. In cosmetic and skin care products, titanium dioxide

561-495: A photocatalyst, attempts have been made to mineralize pollutants (to convert into CO 2 and H 2 O) in waste water. The photocatalytic destruction of organic matter could also be exploited in coatings with antimicrobial applications. Although nanosized anatase TiO 2 does not absorb visible light, it does strongly absorb ultraviolet (UV) radiation ( hv ), leading to the formation of hydroxyl radicals. This occurs when photo-induced valence bond holes (h vb ) are trapped at

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612-468: A pigment, titanium dioxide can be added to paints, cements, windows, tiles, or other products for its sterilizing, deodorizing, and anti-fouling properties, and is used as a hydrolysis catalyst . It is also used in dye-sensitized solar cells , which are a type of chemical solar cell (also known as a Graetzel cell). The photocatalytic properties of nanosized titanium dioxide were discovered by Akira Fujishima in 1967 and published in 1972. The process on

663-477: A result, biphasic titanium dioxide is often considered to possess enhanced functionality as a photocatalyst. It has been reported that titanium dioxide, when doped with nitrogen ions or doped with metal oxide like tungsten trioxide, exhibits excitation also under visible light. The strong oxidative potential of the positive holes oxidizes water to create hydroxyl radicals . It can also oxidize oxygen or organic materials directly. Hence, in addition to its use as

714-458: A small number of crystallites from the mean crystal size and modifies the physical behaviour of TiO 2 . The optical properties of the finished pigment are highly sensitive to purity. As little as a few parts per million (ppm) of certain metals (Cr, V, Cu, Fe, Nb) can disturb the crystal lattice so much that the effect can be detected in quality control. Approximately 4.6 million tons of pigmentary TiO 2 are used annually worldwide, and this number

765-474: Is expected to increase as use continues to rise. TiO 2 is also an effective opacifier in powder form, where it is employed as a pigment to provide whiteness and opacity to products such as paints , coatings , plastics , papers , inks , foods , supplements , medicines (i.e. pills and tablets), and most toothpastes ; in 2019 it was present in two-thirds of toothpastes on the French market. In paint, it

816-557: Is found as a mineral in magmatic rocks and hydrothermal veins, as well as weathering rims on perovskite . TiO 2 also forms lamellae in other minerals. The largest TiO 2 pigment processors are Chemours , Venator , Kronos  [ de ] , and Tronox . Major paint and coating company end users for pigment grade titanium dioxide include Akzo Nobel , PPG Industries , Sherwin Williams , BASF , Kansai Paints and Valspar . Global TiO 2 pigment demand for 2010

867-765: Is found in the majority of physical sunscreens because of its strong UV light absorbing capabilities and its resistance to discolouration under ultraviolet light. This advantage enhances its stability and ability to protect the skin from ultraviolet light. Nano-scaled (particle size of 20–40 nm) titanium dioxide particles are primarily used in sunscreen lotion because they scatter visible light much less than titanium dioxide pigments, and can give UV protection. Sunscreens designed for infants or people with sensitive skin are often based on titanium dioxide and/or zinc oxide , as these mineral UV blockers are believed to cause less skin irritation than other UV absorbing chemicals. Nano-TiO 2 , which blocks both UV-A and UV-B radiation,

918-447: Is generally used in cosmetic and sunscreen products due to it not possessing any observed ability to damage the skin under normal conditions and having a higher UV absorption . In 2016 Scientific Committee on Consumer Safety (SCCS) tests concluded that the use of nano titanium dioxide (95–100% rutile, ≦5% anatase) as a UV filter can be considered to not pose any risk of adverse effects in humans post-application on healthy skin, except in

969-511: Is known as riesite. Both of which can be found at the Ries crater in Bavaria . It is mainly sourced from ilmenite , which is the most widespread titanium dioxide-bearing ore around the world. Rutile is the next most abundant and contains around 98% titanium dioxide in the ore. The metastable anatase and brookite phases convert irreversibly to the equilibrium rutile phase upon heating above temperatures in

1020-413: Is often referred to offhandedly as "brilliant white", "the perfect white", "the whitest white", or other similar terms. Opacity is improved by optimal sizing of the titanium dioxide particles. In food, it is commonly found in ice creams, chocolates, all types of candy, creamers, desserts, marshmallows, chewing gum, pastries, spreads, dressings, cakes, some cheeses, and many other foods. When deposited as

1071-415: Is orthorhombic. The oxygen substructures are all slight distortions of close packing : in rutile, the oxide anions are arranged in distorted hexagonal close-packing, whereas they are close to cubic close-packing in anatase and to "double hexagonal close-packing" for brookite. The rutile structure is widespread for other metal dioxides and difluorides, e.g. RuO 2 and ZnF 2 . Molten titanium dioxide has

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1122-524: Is produced in varying particle sizes which are both oil and water dispersible, and in certain grades for the cosmetic industry. It is also a common ingredient in toothpaste. The exterior of the Saturn V rocket was painted with titanium dioxide; this later allowed astronomers to determine that J002E3 was likely the S-IVB stage from Apollo 12 and not an asteroid . Titanium dioxide is an n-type semiconductor and

1173-643: Is recounted in the 2018 documentary film The Devil We Know , which centers on Parkersburg, West Virginia, where the DuPont facility that manufactured Teflon was located. The documentary follows the personal stories and tribulations of several people who worked at the Parkersburg facility. In June 2023, Chemours (together with Dupont and Corteva) settled claims that they contaminated U.S. public water systems with toxic " forever chemicals " (PFAS) for $ 1.19 billion, with Chemours paying $ 592 million and DuPont and Corteva paying

1224-406: Is reportedly most pronounced at the {001} planes of anatase, although the {101} planes are thermodynamically more stable and thus more prominent in most synthesised and natural anatase, as evident by the often observed tetragonal dipyramidal growth habit . Interfaces between rutile and anatase are further considered to improve photocatalytic activity by facilitating charge carrier separation and as

1275-405: Is surpassed only by a few other materials (see list of indices of refraction ). Titanium dioxide crystal size is ideally around 220 nm (measured by electron microscope) to optimize the maximum reflection of visible light. However, abnormal grain growth is often observed in titanium dioxide, particularly in its rutile phase. The occurrence of abnormal grain growth brings about a deviation of

1326-401: Is the inorganic compound derived from titanium with the chemical formula TiO 2 . When used as a pigment , it is called titanium white , Pigment White 6 ( PW6 ), or CI 77891 . It is a white solid that is insoluble in water, although mineral forms can appear black. As a pigment, it has a wide range of applications, including paint , sunscreen , and food coloring . When used as

1377-542: Is the manufacturer of Teflon , the brand name of polytetrafluoroethylene (PTFE), known for its anti-stick properties. It also produces titanium dioxide and refrigerant gases . It is currently being sued by the PA Attorney General, for knowingly exposing the public to PFAS. In October 2013, DuPont announced that it was planning to spin off its " performance chemicals " business into a new publicly traded company in mid-2015. DuPont filed its initial Form 10 with

1428-716: Is used as a pigment, sunscreen and a thickener . As a sunscreen, ultrafine TiO 2 is used, which is notable in that combined with ultrafine zinc oxide , it is considered to be an effective sunscreen that lowers the incidence of sun burns and minimizes the premature photoaging , photocarcinogenesis and immunosuppression associated with long term excess sun exposure. Sometimes these UV blockers are combined with iron oxide pigments in sunscreen to increase visible light protection. Titanium dioxide and zinc oxide are generally considered to be less harmful to coral reefs than sunscreens that include chemicals such as oxybenzone , octocrylene and octinoxate . Nanosized titanium dioxide

1479-436: Is used extensively in plastics and other applications as a white pigment or an opacifier and for its UV resistant properties where the powder disperses light – unlike organic UV absorbers – and reduces UV damage, due mostly to the particle's high refractive index. In ceramic glazes , titanium dioxide acts as an opacifier and seeds crystal formation. It is used as a tattoo pigment and in styptic pencils . Titanium dioxide

1530-528: Is used in dye-sensitized solar cells . It is also used in other electronics components such as electrodes in batteries. Between 2002 and 2022, there were 459 patent families that describe the production of titanium dioxide from ilmenite . The majority of these patents describe pre-treatment processes, such as using smelting and magnetic separation to increase titanium concentration in low-grade ores, leading to titanium concentrates or slags. Other patents describe processes to obtain titanium dioxide, either by

1581-406: Is used in fiber and paper applications. The sulfate process is run as a batch process ; the chloride process is run as a continuous process . In chloride process , the ore is treated with chlorine and carbon to give titanium tetrachloride , a volatile liquid that is further purified by distillation. The TiCl4 is treated with oxygen to regenerate chlorine and produce the titanium dioxide. In

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1632-429: Is used in sunscreens and other cosmetic products. The EU Scientific Committee on Consumer Safety considered nano sized titanium dioxide to be safe for skin applications, in concentrations of up to 25 percent based on animal testing. The risk assessment of different titanium dioxide nanomaterials in sunscreen is currently evolving since nano-sized TiO 2 is different from the well-known micronized form. The rutile form

1683-408: Is yet another ore. Star sapphires and rubies get their asterism from oriented inclusions of rutile needles. Titanium dioxide occurs in nature as the minerals rutile and anatase . Additionally two high-pressure forms are known minerals: a monoclinic baddeleyite -like form known as akaogiite , and the other has a slight monoclinic distortion of the orthorhombic α-PbO 2 structure and

1734-535: The European Food Safety Authority (EFSA) ruled that as a consequence of new understandings of nanoparticles , titanium dioxide could "no longer be considered safe as a food additive", and the EU health commissioner announced plans to ban its use across the EU, with discussions beginning in June 2021. EFSA concluded that genotoxicity —which could lead to carcinogenic effects—could not be ruled out, and that

1785-511: The SEC in December 2014 and announced that the new company would be called "The Chemours Company." The name is a portmanteau of the words chemical and Nemours, a nod to DuPont's full name, E. I. du Pont de Nemours & Co. The company's CC ticker symbol, is also a play on DuPont's DD symbol; it was also formerly used by the electronics retail Circuit City prior to its bankruptcy in 2009. The spin-off

1836-568: The Sorel-Tracy plant of QIT-Fer et Titane and the Eramet Titanium & Iron smelter in Tyssedal Norway. The Becher process is another method for the production of synthetic rutile from ilmenite. It first oxidizes the ilmenite as a means to separate the iron component. For specialty applications, TiO 2 films are prepared by various specialized chemistries. Sol-gel routes involve

1887-1010: The Chief Executive Officer (CEO) Mark Newman, Chief Financial Officer (CFO) Jonathan Lock, and Financial Controller Camela Wisel were placed on administrative leave by the company's board due to members of senior management delaying payments to some vendors to aid incentive compensation and obtain a bigger bonus. The officer's actions violated the company's standards for ethics. Chemours manufactures and sells performance chemicals falling within three segments: Titanium Technologies ( titanium dioxide ); Fluoroproducts ( refrigerants and industrial fluoropolymer resins and derivatives including Freon , Teflon , Viton , Nafion , ECCtreme ECA and Krytox ); and Chemical Solutions ( cyanide , sulfuric acid , aniline , methylamines , and reactive metals). Titanium dioxide 3.15   eV (rutile) Titanium dioxide , also known as titanium(IV) oxide or titania / t aɪ ˈ t eɪ n i ə / ,

1938-684: The Hotel duPont, and a branch of M&T Bank . Under pressure from activist shareholders, the company first leased the building's DuPont Playhouse in January 2015 to the Grand Opera House , which renamed it The Playhouse on Rodney Square. The entire structure and the hotel business were then sold to Wilmington-based developer Buccini/Pollin in January 2018. The new owners have leased the building's office space back to Chemours, will continue to lease The Playhouse to The Grand Opera House, and have promised to keep

1989-504: The case the application method would lead to substantial risk of inhalation (ie; powder or spray formulations). This safety opinion applied to nano TiO 2 in concentrations of up to 25%. Initial studies indicated that nano-TiO 2 particles could penetrate the skin, causing concern over its use. These studies were later refuted, when it was discovered that the testing methodology couldn't differentiate between penetrated particles and particles simply trapped in hair follicles and that having

2040-571: The hotel operating. Hotel du Pont was where Joe Biden announced his candidacy for the 1972 United States Senate election in Delaware . Chemours The Chemours Company ( / k ɛ ˈ m ɔːr z / , kem- ORZ ) is an American chemical company that was founded in July 2015 as a spin-off from DuPont . It has its corporate headquarters in Wilmington, Delaware , United States. Chemours

2091-421: The hydrolysis of titanium alkoxides such as titanium ethoxide : A related approach that also relies on molecular precursors involves chemical vapor deposition . In this method, the alkoxide is volatilized and then decomposed on contact with a hot surface: First mass-produced in 1916, titanium dioxide is the most widely used white pigment because of its brightness and very high refractive index , in which it

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2142-739: The lattice structure of the surface layer of titanium dioxide nanocrystals, permitting infrared absorption. Visible-light-active nanosized anatase and rutile has been developed for photocatalytic applications. In 1995 Fujishima and his group discovered the superhydrophilicity phenomenon for titanium dioxide coated glass exposed to sun light. This resulted in the development of self-cleaning glass and anti-fogging coatings. Nanosized TiO 2 incorporated into outdoor building materials, such as paving stones in noxer blocks or paints, could reduce concentrations of airborne pollutants such as volatile organic compounds and nitrogen oxides . A TiO 2 -containing cement has been produced. Using TiO 2 as

2193-469: The production of titanium dioxide are companies from China, Australia and the United States, reflecting the major contribution of these countries to industrial production. Chinese companies Pangang and Lomon Billions Groups hold major patent portfolios. Nanosized titanium dioxide, particularly in the anatase form, exhibits photocatalytic activity under ultraviolet (UV) irradiation. This photoactivity

2244-423: The range 600–800 °C (1,110–1,470 °F). Titanium dioxide has twelve known polymorphs – in addition to rutile, anatase, brookite, akaogiite and riesite, three metastable phases can be produced synthetically ( monoclinic , tetragonal , and orthorhombic ramsdellite-like), and four high-pressure forms (α-PbO 2 -like, cotunnite -like, orthorhombic OI, and cubic phases) also exist: The cotunnite -type phase

2295-522: The rest. In September 2023, a court in The Netherlands declared Chemours liable for pollution caused by the Teflon producing plant in the city of Dordrecht , South Holland. The court stated that Chemours' predecessor DuPont had willingly withheld crucial information between 1984 and 1998 about the harmful effects of the substances it used and emitted, which made the pollution unlawful. In February 2024,

2346-413: The sulfate process, ilmenite is treated with sulfuric acid to extract iron(II) sulfate pentahydrate . This process requires concentrated ilmenite (45–60% TiO 2 ) or pretreated feedstocks as a suitable source of titanium. The resulting synthetic rutile is further processed according to the specifications of the end user, i.e. pigment grade or otherwise. Examples of plants using the sulfate process are

2397-561: The surface of TiO 2 leading to the formation of trapped holes (h tr ) that cannot oxidize water. Anatase can be converted into non-carbon nanotubes and nanowires . Hollow TiO 2 nanofibers can be also prepared by coating carbon nanofibers by first applying titanium butoxide . Titanium dioxide is insoluble in water, organic solvents, and inorganic acids. It is slightly soluble in alkali , soluble in saturated potassium acid carbonate, and can be completely dissolved in strong sulfuric acid and hydrofluoric acid after boiling for

2448-551: The surface of the titanium dioxide was called the Honda-Fujishima effect  [ ja ] . In thin film and nanoparticle form, titanium dioxide has the potential for use in energy production: As a photocatalyst, it can break water into hydrogen and oxygen. With the hydrogen collected, it could be used as a fuel. The efficiency of this process can be greatly improved by doping the oxide with carbon. Further efficiency and durability has been obtained by introducing disorder to

2499-399: Was 5.3 Mt with annual growth expected to be about 3–4%. The production method depends on the feedstock. In addition to ores, other feedstocks include upgraded slag . Both the chloride process and the sulfate process (both described below) produce titanium dioxide pigment in the rutile crystal form, but the sulfate process can be adjusted to produce the anatase form. Anatase, being softer,

2550-510: Was claimed to be the hardest known oxide with the Vickers hardness of 38 GPa and the bulk modulus of 431 GPa (i.e. close to diamond's value of 446 GPa) at atmospheric pressure. However, later studies came to different conclusions with much lower values for both the hardness (7–20 GPa, which makes it softer than common oxides like corundum Al 2 O 3 and rutile TiO 2 ) and bulk modulus (~300 GPa). Titanium dioxide (B)

2601-577: Was completed on July 1, 2015, and Chemours' stock began trading on the New York Stock Exchange on the same date. Chemours has assumed various liabilities arising from lawsuits against DuPont. Additionally, Chemours' plant in Bladen County, North Carolina , was found to be dumping vast quantities of a chemical dubbed " GenX ", a precursor of Teflon , into the Cape Fear River . This story

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