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Iron-based Catalysis toward Biomass Processing
Published in Piyal Mondal, Mihir Kumar Purkait, Green Synthesized Iron-based Nanomaterials, 2023
Piyal Mondal, Mihir Kumar Purkait
Limonite is another iron ore popular as a pyrolysis catalyst; it consists of a mixture of hydrated iron (III) oxide – hydroxide in varying compositions. The generic formula is often written as FeO(OH)n. H2O, and limonite is one of the three principal iron ores, the others being hematite and magnetite. In an application of limonite ore, a pyrolysis of lignins has produced high-quality bio-oils containing 55% alkyl phenolics and 27% aromatics, with the use of limonite as catalyst (Hita et al., 2018). Similarly, Virginie et al. (2012) have compared the catalytic activity of iron containing olivine to the original olivine in the pyrolysis of pine wood and found that the tar yield could be significantly reduced by using iron-olivine. Furthermore, they have noted that iron-olivine not only served as a catalyst for tar reduction, but also acted as oxygen carrier during the biomass gasification. In addition, Wei et al. (2017) compared the gasification of lignin pellets with, and without, the addition of iron ore and found that the gaseous yield with the catalyst was much higher than the conventional biomass gasification in the temperature range of 900°C–1060°C.
Wetlands Ecosystems: Natural Water Purifiers?
Published in Donald A. Hammer, Constructed Wetlands for Wastewater Treatment, 2020
Donald A. Hammer, Robert K. Bastian
It is no secret that natural wetlands can remove iron, manganese, and other metals from acid drainage − they have been doing it for geological ages. In fact, accumulations of limonite, or bog iron, were mined as the source of ore for this country’s first ironworks and for paint pigment. Limonite deposits are most common in the bog regions of Connecticut, Massachusetts, Pennsylvania, New York, and elsewhere along the Appalachians. Wetlands were abundant in parts of the Tennessee Valley during past ages, and significant bog iron deposits are found in Virginia, Tennessee, Georgia, and Alabama. Although now of limited economic importance in the United States, bog iron is still a significant source of iron ore in northern Europe.
Minerals
Published in F.G.H. Blyth, M. H. de Freitas, A Geology for Engineers, 2017
F.G.H. Blyth, M. H. de Freitas
The name limonite is used as a field term to denote hydrated oxides of iron which are poorly crystallized. They are brown in colour, yellowish brown to yellow when earthy, and form coatings on rock joints and weathered surfaces, and concretions. The principal constituent is goethite which results from the alteration of Fe-bearing minerals, and in residual deposits may be mixed with clay and other materials (cf. laterite, p. 38). Goethite produces the ‘iron-hat’, or gossan that mantles a weathered exposure of sulphide ores (see p. 89). It may form the iron-pan in bogs and tropical soils.
Pelletization characteristics of artificial and natural magnetite and their mixtures
Published in Mineral Processing and Extractive Metallurgy, 2021
Manman Lu, Hanquan Zhang, Hong Yu, Zeqiang Zhang
Samples of artificial magnetite were obtained from a mining company in Datian (Fujian province, China). The manufacturing technique of this company is depicted in Figure 1. A sample of natural magnetite concentrate dy was obtained from the Chengchao iron mine of Wuhan Iron and Steel (Group) Corp. (WISCO). As shown in Table 1, the total iron content of the low-grade limonite (Fe2O3·nH2O) was 41.31%. The iron content of the artificial magnetite concentrate obtained by magnetising roasting − magnetic separation was 61.34%. The iron content of natural magnetite concentration was 64.33%, while the content of harmful elements such as S and P was very low. On the other hand, the SiO2 content of the artificial magnetite concentrate was 8.09%. The iron mineral phases of the raw materials are shown in Table 2. After magnetic roasting, the low-grade limonite was converted to magnetite.
Antibacterial, UV protection, flame retardancy and coloration properties of cotton fabrics coated with polyacrylate polymer containing various iron ores
Published in The Journal of The Textile Institute, 2018
Nurhan Onar Camlibel, Buket Arik, Ozan Avinc, Arzu Yavas
Iron(III) oxides make a pigment called ochre and iron ores are named differently according to the color of the ochre; for instance hematite, limonite, and goethite are known as red, yellow, and brown ochres and are crystalline iron minerals, respectively (Roelofs & Petillion, 2012; Xu, Xu, Li, & Deng, 2017). Among those, Hematite (Fe2O3) is the most known and the most commonly used iron ore. Goethite (α-FeOOH) is the second most common natural ore and generally contains approximately 80 to 90% Fe2O3. Limonite (α-FeOOH.n(H2O)) is one of principal iron ores and commonly composed from the hydration of hematite and magnetite. China, Australia, Brazil, India, and Russia are known to be leading countries in iron ore production (U.S. Geological Survey, 2015). In the case of Turkey, it is estimated that 82.5 million tons of iron ore reserves exist in Turkey (IBP, 2015). Iron ores capture great attention for many different application fields such as magnetic, catalytic, pigments, drug carriers, adsorption, waste water treatment recently due to their high availability, low cost, ease of application, and versatile properties. Moreover investigations regarding their potential usage have recently increased (Abbasi, Ghanbari, Salavati-Niasari, & Hamadanian, 2016; Ahmadi Golsefidi, Abbasi, Abrodi, & Abbasi, 2016; Kirwan, Fawell, & Van Bronswijk, 2003, 2004; Omoike & Chorover, 2006; Parikh & Chorover, 2006).
Enhancement of anti-corrosion and mechanical properties of alkyd-based protective paints for steel petroleum structures incorporating natural limonite pigment
Published in Cogent Engineering, 2018
M.I. Abdou, Hany El-Sayed Ahmed, M.A. Wahab Gaber, A.M. Fadl
Earthy pigments varying from dull yellow to red and brown are commonly called ochre’s in the economic geology, mining industry, and painting. Ochre’s are defined as clays used to make the earth colors; in pigment terminology, the word ochre is predominantly used as a synonym for yellow ochre (Hradil, Grygar, Hradilová, & Bezdička, 2003). Limonite is the significant colored mineral found in a natural state suitable for use as a pigment after being pulverized to the desired size. The name “limonite” was given to many of the yellowish to yellowish brown iron oxides produced during the weathering of iron-bearing rocks or deposited as bog, lake, and shallow marine sediments. The global production of iron oxide pigments in 2000 was estimated to be 1,500,000 Mt., and 87% of the total market is attributed to industrial applications (Will, 2004). Limonite is an iron ore consisting of a mixture of hydrated iron (III) oxide-hydroxides in varying composition. The generic formula is frequently written as FeO (OH)·nH2O, although this is not entirely accurate as the ratio of oxide to hydroxide can vary quite widely. Iron oxides pigments have the advantage of low cost, permanency, and non-toxicity. In the last century, the chemical industry improved on nature by developing a complete range of synthetic iron oxide pigments (IOPs) that surpass the pigments produced from natural iron ores in uniformity, color quality, and chemical purity. An important characteristic of a pigment is its color.