Carbon minerals

Secondary minerals. As weathering of primary minerals proceeds, ions are released into solution, and new minerals are formed. These new minerals, called secondary minerals, include layer silicate clay minerals, carbonates, phosphates, sulfates and sulfides, different hydroxides and oxyhydroxides of Al, Fe, Mn, Ti, and Si, and non-crystalline minerals such as allophane and imogolite. Secondary minerals, such as the clay minerals, may have a specific surface area in the range of 20-800 m /g and up to 1000 m /g in the case of imogolite (Wada, 1985). Surface area is very important because most chemical reactions in soil are surface reactions occurring at the interface of solids and the soil solution. Layer-silicate clays, oxides, and carbonates are the most widespread secondary minerals. 

In eomparison, the Te-type deposits contain fine-grained quartz, chalcedonic quartz, sericite, barite, adularia, ehlorite/smectite interstratified mixed layer clay mineral and rarely anatase. Carbonates and Mn-minerals are very poor in the Te-type deposits and they do not coexist with Te-minerals. Carbonates are abundant and barite is absent in the Se-type deposits. The grain size of quartz in the Te-type deposits is very fine, while large quartz crystals are common in the Se-type deposits although they formed in a late stage and do not coexist with Au-Ag minerals. 

Calcium carbonate is also the main constituent of the shells of sea animals, which make their shells from elements acquired from the surrounding waters. Now, the degree of fractionation of the oxygen isotopes as well as the formation of mineral carbonates and of animal shells in sea waters are determined on the basis of the temperature-dependent fractionation of the isotopes of oxygen the oxygen isotope composition of these materials reflects, therefore, the temperature at the time of their formation. Thus determining the isotope ratio between the stable isotopes of oxygen... 

Allen D.J. and Brent G.F. Sequestering C02 by mineral carbonation stability against acid rain exposure. 2010 Environmental Science Technology 44(7) 2735-2739. 

Mineral carbonation is a new and, consequently, less studied method of sequestration. Mineral resources are plentiful for storing all the carbon that could ever be released in the consumption of fossil fuels. This sequestration process offers a safe and permanent method of C02 disposal, since there is almost no possibility of accidental release of C02 from the disposal site as C02 is chemically incorporated into the mineral and immobilized. Furthermore, the reactions that bind C02 to the mineral are exothermic in nature leading to the formation of thermodynamically stable carbonate forms (IPCC, 2005). 

C02 sequestration by mineral carbonation. (From Goldberg, P., Mineral Sequestration Team Activities, Introduction, Issues Plans, Powerpoint Presentation for Mineral Carbonation Workshop August 8, 2001 sponsored byNETL. http //www.netl.doe.gov/publications/proceedings/01/minecarb/goldberg.pdf, 2001. With permission.)... 

Vreca, P., Pirc, S., Sajn, R., 2001. Natural and anthropogenic influences on geochemistry of soils in the terrains of barren and mineralized carbonate rocks in the Pb - Zn mining district of Mezica, Slovenia. Journal of Geochemistry Exploration, 74, 99-108. 

Chen, Y.-W., et al. 2005. Photochemical behavior of inorganic and organic selenium compounds in various aqueous solutions. Analytica Chi mica Acta, 545(2), 142-148. Chester, R. Hughes, M.J. 1967. A chemical technique for the separation of ferromanganese minerals, carbonate minerals... 

The fact that the carbonates of foraminifera burried in marine sediments can be used as a "memory storage" for Cd2+ present in the sea when the foraminifera were formed (Delaney and Boyle, 1987) is evidence for the non-reversibility or extremely slow reversibility of biogenic mineral carbonates. 

Because samples of suspended, sinking, and sedimentary marine particles often contain appreciable amounts of clay minerals, carbonate, and opal, any quantification method for organic elements must avoid interference from these mineral types. 

Cu and Zn enter sedimentary material in substantial proportions, both in the structure of minerals (carbonates, clays) and adsorbed on surfaces. Boyle (1981) showed that foraminiferal tests may contain Zn in excess of a few ppm. Partitioning of Cu and Zn between water and carbonates has been investigated by Rimstidt et al. (1998). The crystal chemistry of Cu and Zn in goethite has been investigated by EXAFS by Manceau et al. (2000). Typical Zn and Cu concentrations in FeMn nodules and encrustations are 500-1000 ppm and 800-6000 ppm, respectively (e.g., Albarede et al. 1997b). 

This information is reported as the percentage that each of the clay mineral type contributes to total identifiable clay mineral content of the noncarbonate clay-sized fraction of the surface sediments. These percentages were determined by x-ray diffraction, which is luiable to identify noncrystalline solids. Using this technique, clay minerals were found to comprise about 60% of the mass of carbonate-free fine-grained fraction. Most of the noncrystalline soUds are probably mixed-layer clay minerals. Carbonate was removed to facilitate the x-ray diffraction characterization of the clay minerals. In some cases, roimd off errors cause the sum of the percentages of kaolinite, illite, montmorillonite, and chlorite to deviate slightly from 100%. 

Also in the testing phase is mineral carbonation in which CO2 is reacted with a calcium or magnesium oxide to form the carbonate salt. 

Synonyms Plumbago black lead mineral carbon... 

Coal contains detrital minerals that were deposited along with the plant material, and authigenic minerals that were formed during coalification. The abundance of mineral matter in coal varies considerably with its source, and is reported to range between 9.05 and 32.26 wt% (Valkovic 1983). Minerals found in coal include (Table 2) aluminosilicates, mainly clay minerals carbonates, such as, calcite, ankerite, siderite, and dolomite sulphides, mainly pyrite (FeS2) chlorides and silicates, principally quartz. Trace elements in coal are commonly associated with one or more of these minerals (see Table 2). 

Mild Mercury Chloride Milk Acid Mineral Carbon Mineral Charcoal Mineral Colza Oil Mineral Oil Mineral Seal Oil Mineral Spirits Mitis Green... 

Borg and Drake (2005) have determined the timing of aqueous alteration events in Martian meteorites from the ages of secondary minerals. Carbonates in ALH 84001 formed at 3.9 Ga, iddingsite in nakhlites formed -630 Myr ago, and salts in shergottites formed sometime after the crystallization of these rocks, 170 Myr ago. 

The classical approach to mineralisation, conducted openly in a fume-hood in the presence of acidic vapours, lends itself to cross-contamination. This operation is long and fastidious and has not changed in over a century. Beyond the practical problems involved, it is impossible to treat some matrices under these conditions (e.g. refractory or volatile materials, certain minerals, carbons and heavy oils). 

From the vertical distributions of various components, the mineralized carbon (Miner. C) and nitrogen (Miner. N) at various depths were calculated according to the following equations ... 

The calculated values are summarized in Table III. The amounts of total mineralized carbon and nitrogen in a vertical water column of Lake Kizald-ko, with a sectional area of 100 sq. cm. and with the same depth as the lake s are as follows ... 

From the vertical distributions of various components, the mineralized carbon (Miner. C) and nitrogen (Miner. N) at various depths were calculated. On the basis of the calculated values, the ratio of Miner. C/Miner. N in a vertical water column of Lake Kizaki-ko was estimated to be 2.83, which is considerably smaller than that of plankton. 

As expected, gaseous hydrocarbon yields and mineral carbonate decomposition increase with increases in temperature (Figure 9). The results are very encouraging—in all tests, over 90% of the organic carbon was recovered as gaseous and liquid products. At 1200°F, over 80% of the organic carbon was converted to liquids at 1400°F, over 60% was converted to gas. 

More organic carbon could probably have been removed at 1200°F if a longer residence time had been provided. This higher space velocity probably also caused a relatively lower mineral carbonate decomposition. 

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