TiO2 as white pigment and valorization of the waste coming from its production

Zinc oxide (ZnO) is an inorganic compound used for its antiseptic and skin healing properties. It is an excellent protective filter against UV radiation and it can be used as white pigment in pharmaceutical preparations. In this study, nano-ZnO particles were obtained by ultrasound treatment, and respectively by repeated freezing/heating process. The influence of synthesis method and of ultrasound generator parameters on the particles size and stability was observed. The results reveal that were obtained samples with a very good stability and sizes between 15 and 96 nm. It was found that synthesis based on ultrasound treatment lead to the formation of nanoparticles with lower sizes.

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Radiocarbon dating of lead white: novel application in the study of polychrome sculpture

Scientific Reports ◽

10.1038/s41598-021-91814-y ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sara Sá ◽

Laura Hendriks ◽

Isabel Pombo Cardoso ◽

Irka Hajdas

Keyword(s):

Radiocarbon Dating ◽

Lead White ◽

Human History ◽

White Pigment ◽

Multidisciplinary Study ◽

Paint Systems ◽

Technological Advances ◽

Polychrome Sculpture ◽

Cultural Heritage Objects ◽

Source Of Information

AbstractRecently, radiocarbon dating underwent considerable technological advances allowing unprecedented sample size downscaling. These achievements introduced novel opportunities in dating cultural heritage objects. Within this pioneering research, the possibility of a direct 14C dating of lead white pigment and organic binder in paint samples was investigated on polychrome sculptures, a foremost artistic expression in human history. The polychromy, an indivisible part of polychrome sculpture, holds a key role in the interpretation and understanding of these artworks. Unlike in other painted artworks, the study of polychromies is repeatedly hampered by repaints and degradation. The omnipresence of lead white within the original polychromy was thus pursued as dating proxy. Thermal decomposition allowed bypassing geologic carbonate interferences caused by the object's support material, while an added solvent extraction successfully removed conservation products. This radiocarbon dating survey of the polychromy from 16 Portuguese medieval limestone sculptures confirmed that some were produced within the proposed chronologies while others were revised. Within this multidisciplinary study, the potential of radiocarbon dating as a complementary source of information about these complex paint systems guiding their interpretation is demonstrated. The challenges of this innovative approach are highlighted and improvements on sampling and sample preparation are discussed.

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Preparation, Decomposition and Characterizations of Bangka - Indonesia Ilmenite (FeTiO3) Derived by Hydrothermal Method Using Concentrated NaOH Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.750 ◽

2012 ◽

Vol 535-537 ◽

pp. 750-756 ◽

Cited By ~ 3

Author(s):

Latifa Hanum Lalasari ◽

Florentinus Firdiyono ◽

Akhmad Herman Yuwono ◽

Sri Harjanto ◽

Bambang Suharno

Keyword(s):

Intermediate Phase ◽

Hydrothermal Process ◽

Sodium Titanate ◽

Titanium Metal ◽

White Pigment ◽

Naoh Solution ◽

Metal Titanium ◽

Tio2 Pigment ◽

Impurity Elements ◽

Operation Cost

Ilmenite is an economically important and interesting mineral. It is found as a by-product of tin mining in Bangka Indonesia. This mineral has can be used as the source of making titanium metal, titanium dioxide (TiO2) pigment and material for photo catalysts. However, the synthesis of TiO2 from ilmenite using both sulfate and chloride processes still has faced a major problem to obtain white pigment of high purity and lower operation cost. This is mainly due to Fe2O3 impurity in TiO2 pigment which cannot be easily decomposed. Therefore, this study is aimed at investigating the possibility of using Bangka ilmenite mineral to obtain TiO2 pigments and photocatalysts. For this purpose, , sodium hydroxide (NaOH) was used as decomposition solution via hydrothermal process in a teflon-lined autoclave equipment. The characterization results indicated that Bangka ilmenite contains a significant TiO2 level of more than 30 %, although there still remains some other impurities. Upon decomposition of dissolution using NaOH, was decrease in impurity elements down to 60 %. The decomposition process of ilmenite was optimum at NaOH concentration of 10 M where the ilmenite decomposes to form an intermediate phase of sodium titanate with the morphological shape of fine threads.

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Influence of titanium oxide-based colourants on the morphological and tribomechanical properties of injection-moulded polyoxymethylene spur gears

Journal of Polymer Engineering ◽

10.1515/polyeng-2019-0170 ◽

2019 ◽

Vol 39 (8) ◽

pp. 774-783

Author(s):

Dominik Schubert ◽

Sebastian Hertle ◽

Dietmar Drummer

Keyword(s):

Titanium Oxide ◽

Mechanical Performance ◽

Core Material ◽

Spur Gears ◽

Delivery Methods ◽

White Pigment ◽

Crystalline Core ◽

Coarse Microstructure ◽

Tribomechanical Properties ◽

Carrier Systems

Abstract Regardless of colouration for functional or aesthetic purposes, technical polymer parts, like gears, require consistent properties. However, there is a lack of research into the effect of colourants on the tribomechanical properties of gears. Therefore, the effects of two pigments, titanium dioxide (white) and chrome antimony titanium oxide (yellow), and three delivery methods, masterbatch, liquid colour and direct compounding, on part morphology, dimensions, tribological and mechanical performance of injection-moulded polyoxymethylene (POM) spur gears are investigated in this paper. The white pigment accelerates the crystallisation of POM, causing fine and highly-crystalline morphological structures and smaller dimensions. However, the yellow pigment decelerates crystallisation, resulting in a coarser morphology with highly crystalline core material and bigger parts. Furthermore, the delivery method affects only the tribomechanical properties. Using a masterbatch decreases loads at break and increases deflection at break, since the carrier material acts as an impact modifier and a weak spot. The liquid colour decreases wear due to lubricating properties, whereas the pure pigments increases abrasion, especially in combination with a coarse microstructure. However, the effects of carrier systems and changes in morphology are always superimposed. Considering the performance and tolerance of technical components, colourants have to be carefully selected to ensure beneficial properties.

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Macroscopic x-ray powder diffraction imaging reveals Vermeer’s discriminating use of lead white pigments in Girl with a Pearl Earring

Science Advances ◽

10.1126/sciadv.aax1975 ◽

2019 ◽

Vol 5 (8) ◽

pp. eaax1975 ◽

Cited By ~ 8

Author(s):

S. De Meyer ◽

F. Vanmeert ◽

R. Vertongen ◽

A. Van Loon ◽

V. Gonzalez ◽

...

Keyword(s):

Optical Properties ◽

Powder Diffraction ◽

Lead White ◽

White Pigment ◽

Microscopic Scale ◽

X Ray ◽

Oil Paintings ◽

Johannes Vermeer ◽

Diffraction Imaging ◽

The 19Th Century

Until the 19th century, lead white was the most important white pigment used in oil paintings. Lead white is typically composed of two crystalline lead carbonates: hydrocerussite [2PbCO3·Pb(OH)2] and cerussite (PbCO3). Depending on the ratio between hydrocerussite and cerussite, lead white can be classified into different subtypes, each with different optical properties. Current methods to investigate and differentiate between lead white subtypes involve invasive sampling on a microscopic scale, introducing problems of paint damage and representativeness. In this study, a 17th century painting Girl with a Pearl Earring (by Johannes Vermeer, c. 1665, collection of the Mauritshuis, NL) was analyzed with a recently developed mobile and noninvasive macroscopic x-ray powder diffraction (MA-XRPD) scanner within the project Girl in the Spotlight. Four different subtypes of lead white were identified using XRPD imaging at the macroscopic and microscopic scale, implying that Vermeer was highly discriminatory in his use of lead white.

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There's a TITANOX® white pigment for every paint requirement

Chemical & Engineering News ◽

10.1021/cen-v039n031.p010 ◽

1961 ◽

Vol 39 (31) ◽

pp. 10

Keyword(s):

White Pigment

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A review of the genus Platyrhina (Chondrichthys: Platyrhinidae) from the northwestern Pacific, with descriptions of two new species

Zootaxa ◽

10.11646/zootaxa.2738.1.2 ◽

2011 ◽

Vol 2738 (1) ◽

pp. 26 ◽

Cited By ~ 4

Author(s):

YUKIO IWATSUKI ◽

KEI MIYAMOTO ◽

KAZUHIRO NAKAYA ◽

JIE ZHANG

Keyword(s):

New Species ◽

Pacific Coast ◽

Northwestern Pacific ◽

Nominal Species ◽

Undescribed Species ◽

White Pigment ◽

Light Yellow ◽

The Pacific ◽

Two New Species ◽

Pacific Species

The genus Platyrhina from the northwestern Pacific was reviewed, including a redescription and neotype proposal for Platyrhina sinensis (Bloch and Schneider 1801), and the description of two new species. Platyrhina limboonkengi Tang 1933 is relegated to the synonymy of P. sinensis, both species having two rows of hooked thorns on the mid-dorsum of the tail. Specimens previously widely identified as P. sinensis, but characterized by one row of such hooked thorns, represented an undescribed species, herein named Platyrhina tangi Iwatsuki, Zhang and Nakaya sp. nov. Platyrhina hyugaensis Iwatsuki, Miyamoto and Nakaya sp. nov., known from specimens limited primarily to the Hyuga Nada Sea, off Miyazaki, the Pacific coast of southern Japan, is similar to P. tangi in having one row of hooked thorns on the mid-dorsum of the trunk and tail, but differs in having larger hooked thorns, not encircled by light yellow or white pigment on the orbital, nape and scapular regions, and a pair of hooked thorns (absent in P. tangi) anteriorly on the scapular region. Nominal species are discussed and key to northwestern Pacific species of Platyrhina is provided.

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Experiments on the Mendelian Inheritance of Eye-colour in the Amphipod Gammarus chevreuxi

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400007256 ◽

1916 ◽

Vol 11 (1) ◽

pp. 18-51 ◽

Cited By ~ 3

Author(s):

E. W. Sexton ◽

M. B. Wing.

Keyword(s):

Second Generation ◽

Mendelian Inheritance ◽

Natural Conditions ◽

White Pigment ◽

Eye Colour ◽

The Many ◽

Retinular Cells

1. Twenty-one thousand, five hundred and fourteen (21,514) amphipods of the species Gammarus chevreuxi Sexton have been examined for eyecolour, 21.302 referred to in this paper, and 212 in other experiments, not included.2. The normal eye-colour of this species is black, with a superficial reticulation of opaque white pigment.3. The pigmentation of the eye is very variable within limits. Eyes have been observed either partially or entirely lacking in the coloured pigment of the retinular cells, or with either a partial or entire lack, or else an excess of the opaque white pigment.4. The red strain appears to have arisen as a “sport” in the second generation of offspring of the first animals captured. No red-eyed animals have yet been found in natural conditions, although many thousands have been brought in from time to time and examined. Those counted for the purpose while the work for this paper was in progress numbered 8697, but this figure does not include the many thousands previously observed. Experiments have been made repeatedly with a view of getting the Red strain again from the Pure Black, but with no success.

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Hepatic and Renal Toxicity Induced by TiO2 Nanoparticles in Rats: A Morphological and Metabonomic Study

Journal of Toxicology ◽

10.1155/2019/5767012 ◽

2019 ◽

Vol 2019 ◽

pp. 1-19 ◽

Cited By ~ 8

Author(s):

Xavier Valentini ◽

Pascaline Rugira ◽

Annica Frau ◽

Vanessa Tagliatti ◽

Raphaël Conotte ◽

...

Keyword(s):

Oxidative Stress ◽

White Pigment ◽

Lack Of Information ◽

Physiological Alterations ◽

Liver And Kidney ◽

Enzymatic Markers ◽

Treatment Dosage ◽

Kidney Functions ◽

The Impact ◽

Different Doses

Titanium dioxide (TiO2) nanoparticles (NPs) are produced abundantly and are frequently used as a white pigment in the manufacture of paints, foods, paper, and toothpaste. Despite the wide ranges of uses, there is a lack of information on the impact of NPs on animal and human health. In the present study, rats were exposed to different doses of TiO2 nanoparticles and sacrificed, respectively, 4 days, 1 month, and 2 months after treatment. Dosage of TiO2 in tissues was performed by ICP-AES and revealed an important accumulation of TiO2 in the liver. The nanoparticles induced morphological and physiological alterations in liver and kidney. In the liver, these alterations mainly affect the hepatocytes located around the centrilobular veins. These cells were the site of an oxidative stress evidenced by immunocytochemical detection of 4-hydroxynonenal (4-HNE). Kupffer cells are also the site of an important oxidative stress following the massive internalization of TiO2 nanoparticles. Enzymatic markers of liver and kidney functions (such as AST and uric acid) are also disrupted only in animals exposed to highest doses. The metabonomic approach allowed us to detect modifications in urine samples already detectable after 4 days in animals treated at the lowest dose. This metabonomic pattern testifies an oxidative stress as well as renal and hepatic alterations.

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On metal and ‘spoiled’ wine: analysing psimythion (synthetic cerussite) pellets (5th–3rd centuries BCE) and hypothesising gas-metal reactions over a fermenting liquid within a Greek pot

Archaeological and Anthropological Sciences ◽

10.1007/s12520-020-01184-1 ◽

2020 ◽

Vol 12 (10) ◽

Author(s):

E. Photos-Jones ◽

P. Bots ◽

E. Oikonomou ◽

A. Hamilton ◽

C. W. Knapp

Keyword(s):

Early Period ◽

Mineralogical Composition ◽

Acetic Acid Bacteria ◽

Lead White ◽

Lead Carbonate ◽

White Pigment ◽

Metallic Trace Elements ◽

Basic Lead Carbonate ◽

Key Drivers ◽

Greek World

Abstract A Pb-based synthetic mineral referred to as psimythion (pl. psimythia) was manufactured in the Greek world at least since the 6th c BCE and routinely by the 4th c BCE. Theophrastus (On Stones, 56) describes its preparation from metallic Pb suspended over a fermenting liquid. Psimythion is considered the precursor of one of western art’s most prominent white pigments, i.e. lead white (basic lead carbonate or synthetic hydrocerussite). However, so far, and for that early period, published analyses of psimythia suggest that they consisted primarily of synthetic cerussite. In this paper, we set out to investigate how it was possible to manufacture pure cerussite, to the near exclusion of other phases. We examined the chemical and mineralogical composition (pXRF/XRD) of a small number of psimythion pellets found within ceramic pots (pyxis) from Athens and Boeotia (5th–4th c BCE) in the collection of the National Archaeological Museum (NAM), Athens. Analyses showed that the NAM pellets consisted primarily of Pb/cerussite with small amounts of Ca (some samples) and a host of metallic trace elements. We highlight the reference in the Theophrastus text to ‘spoiled wine’ (oxos), rather than ‘vinegar’, as has been previously assumed, the former including a strong biotic component. We carried out DNA sequencing of the pellets in an attempt to establish presence of microorganisms (Acetic Acid Bacteria). None was found. Subsequently, and as a working hypothesis, we propose a series of (biotic/abiotic) reactions which were likely to have taken place in the liquid and vapour phases and on the metal surface. The hypothesis aims to demonstrate that CO2 would be microbially induced and would increase, as a function of time, resulting in cerussite forming over and above hydrocerussite/other Pb-rich phases. Psimythion has for long been valued as a white pigment. What has perhaps been not adequately appreciated is the depth of empirical understanding from the part of psimythion manufacturers of the reactions between abiotic and biotic components within ‘oxos’/pot, as key drivers of minerals synthesis. Ultimately, psimythion manufacture may rest in understanding the nature of ‘oxos’, antiquity’s relatively little researched strongest acid.

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