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Development of oxidation in Zn-Pb deposits in Olkusz area
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
Smithsonite, cerussite, goethite, and lepidocrocite forming limonite accumulations belong to the group of minerals that have developed in the secondary process. Also monheoimite, hydrozincite, jarosite, thallium jarosite, gypsum, epsomite, copiapite and unstable sulphates such as melanterite and goslarite are typical for oxidized zones.
Analysis on Spontaneous Combustion Characteristics of Adding Associated Sulfur Minerals in Coal
Published in Combustion Science and Technology, 2019
Hailin Jia, Hedi Shen, Chenguang Zhai
Melanterite and copiapite are one of the hydrates formed by the reaction of iron sulfate with oxygen in a humid environment (Ackermann et al., 2009; Majzlan et al., 2006). Melanterite and copiapite can be co-existed with pyrite, elemental sulfur, and other substances in the coal seam or coal seam roof rock. Melanterite, copiapite, pyrite, and elemental sulfur will undergo a series of chemical reactions in a humid environment with sufficient oxygen:
Appraisal of environmental, ecological and carcinogenic risk due to heavy metals in a sewage and solid waste contaminated area
Published in Soil and Sediment Contamination: An International Journal, 2023
Shreya Das, Sudip Sengupta, Prasanta Kumar Patra, Pravat Utpal Acharjee, Susanta Kumar Pal
The DTPA-extractable heavy metal content of the studied soil, presented in Table 1, revealed that the available Cd, Pb, Ni and Cr content ranged from 0.72 to 3.76, 28.59 to 87.29, 3.11 to 8.73 and 2.23 to 8.43 mg kg−1 with a mean value of 1.53, 58.48, 6.02 and 4.35 mg kg−1, respectively. Such higher concentrations of the heavy metals above the threshold limit (Supplementary Table 1) in most cases of these soils may be attributed not only to the continuous incorporation of municipal solid wastes and wastewater into agricultural soils but also to the atmospheric pollution as evident from the metal containing aerosols at the roadside of cultivation areas. Similar findings were reported by earlier researchers (Das et al. 2014; Li et al. 2016; Mani et al. 2021; Ripin et al. 2014; Silva et al. 2021). In a study conducted at the same solid-waste disposal ground of Dhapa, Kolkata, West Bengal, Banerjee et al. (2010) reported higher concentration of available Cd, Pb and Cr in soil with the average concentration of 0.72, 11.59 and 2.95 mg kg−1, respectively. In another study conducted at long-term sewage irrigated areas of Kolkata, Saha et al. (2018) found that the concentration of DTPA-extractable Cd, Pb and Ni in soil ranged from 0.34 to 0.49, 6.3 to 10.0, and 1.26 to 3.27 mg kg−1, respectively, which confirms our study findings as well. Such elevated levels of heavy metal content in history-long metal contamination sites is well known (Banerjee et al. 2010; Li et al. 2016; Mani et al. 2021; Silva et al. 2021) and thus our finding finds relevant background. Climate also plays an important role in distribution of heavy metals (Chen et al., 2019). In wet/humid areas like the current study area, high precipitation leads to leaching of heavy metals leading to substantial accumulation in upper as well as lower layers of soil and thereby may enter groundwater sources and thus contaminate ground/surface water resources and soil in the downstream (Sun et al. 2018; Wang et al. 2019). Apart from this during the dry season, several types of efflorescent sulfate group salts such as melanterite, rozenite, chalcanthite, halotrichite, copiapite, jarosite, and schwertmannite groups are found on the upper surface of soil which dissolve quickly during the rainfall and contaminate the surroundings (Punia 2021).