Recently, a study of stable isotope patterns of coexisting pyrite and gypsum at another methane seep site in the northern South China Sea also linked the formation of authigenic gypsum to the oxidation of pyrite and an associated increase in porewater sulfate and acidity (Z.Y. Lin et al., 2016).

Exports In 2018, Pakistan exported $381k in Gypsum, making it the 72nd largest exporter of Gypsum in the world. At the same year, Gypsum was the 608th most exported product in Pakistan. The main destination of Gypsum exports from Pakistan are: China ($291k), South Korea ($31.4k), Chinese Taipei ($28.5k), Sri Lanka ($12.2k), and Bangladesh …

A maximum lithium extraction of approximately 84% was obtained using gypsum at 1050°C. Sodium sulphate produced a superior lithium extraction of up to 97% at 850°C. In all cases iron extraction ...

The sequential batch extraction process is performed by regularly adding fresh leaching medium in the process of the leaching experiment to simulate the leaching …

In the above two medicines, there is one kind of mineral medicine–gypsum. The history of Chinese medicine in China is long and profound. Chinese medicinal materials are divided into three categories according to raw materials: Plants, minerals and animals. Mineral medicine has been used to treat diseases for more than 2000 years.

The pristine gypsum was yellow (Fig. 1 a) with a moisture content of 25%, and the pH of it was 8.The XRD patterns indicated that CaSO 4 ·2H 2 O, CaSO 4 ·0·5H 2 O, NaClO 3 and NaCl were the major crystal phases of the pristine gypsum (Fig. 1 c). SEM images (Fig. 1 b) showed that the particles were rod-like and block-shaped with the sizes …

Gypsum and its products are economical materials in their respective fields. Lime and hydraulic cement plasters compete to a limited extent with gypsum in the plaster field. ... This decrease in the volume of backcast material has eliminated the need for berm walls and has increased extraction 3 to 5 percent. The maximum haul for spoil in the ...

Four Asian countries (Iran, China, Thailand and Japan) produced 43.1Mt of gypsum (29%) in 2022. Two North American countries (the US and Mexico) produced …

Enhanced extraction of heavy metals from gypsum-based hazardous waste by nanoscale sulfuric acid film at ambient conditions J Hazard Mater. ... Beijing 101408, PR China; National Engineering Laboratory for VOCs Pollution Control Materials & Technology, University of Chinese Academy of Sciences, Beijing 101408, PR China; Binzhou Institute ...

Through controlling the phase transformation and chromium species under hydrothermal condition, the Cr(VI) was extracted fully from hazardous Cr(VI)-containing gypsum sludge, with a very high efficiency of more than 99.5%. Scanning transmission electron microscopy, X-ray absorption fine structure, and density functional theory …

Heavy metal-containing gypsum is a widespread hazardous waste. In this work, H + was found to be the most essential factor of the mineralizers in hydrothermal treatment to completely (≥99.8%) extract Cr(VI) from gypsum waste to the supernatant, where the significant growth (from several μm to several hundreds of μm) and perfection …

In 2020, world production was estimated at 270 million tons, the top five producers (in million tons) being China (60.0), United States (39.0), India (28.0), Germany (14.0), and Australia (12.0 ...

Phosphogypsum, as a byproduct of wet-process phosphoric acid reaction, has caused many environmental pollution problems. To improve the property and purity of phosphogypsum in the wet-process phosphoric acid process, a liquid–solid–liquid three-phase acid hydrolysis synergistic extraction reaction system was established by adding …

Materials and chemicals. The raw PG material used in this study was obtained from Sinochem Fuling Chemical Industry Co, Ltd. (Chongqing, China). After this, PG was dried at 40 °C for 12 h to ...

The gypsum concentrate reached the first-grade national standard of PG in China (GB/T 23456–2018), which not only broadened the utilisation and enhanced the application value of PG, but also provided a new insights for the purification of PG. CRediT authorship contribution statement. Mengyao Qi: Conceptualization, Investigation, Formal …

During Jul-Mar FY21, its contribution to GDP remained at 2.38% (Economic Survey FY21). While Pakistan's mineral exports are only about 0.1 % of the world's total exports. In year 2020, Pakistan's total mineral and metals exports were around $ 1.18 Bn as compared to the world's $ 1,490 Bn (UN Comtrade).

Ephedra-Gypsum extract and asprin were administered orally 6 h after the injection of yeast solution and body temperature was measured every 1 h for 8 h. ... China). Plant Material and Ephedra ...

Flue gas desulfurized gypsum (FGD gypsum), mainly originates from thermal power plants, smelters, and large-scale enterprise boilers.This article reviews the production in China and the latest beneficial utilizations of FGD gypsum. China is a large coal-consuming country and has always had serious SO 2 emissions. Therefore, the …

Published: 13 March 2023. Preparation of gypsum with high purity and whiteness from phosphogypsum for CO 2 mineral sequestration. Man Zhang & Xing Fan. Scientific …

China has the worlds largest proven gypsum (CaSO4.2H(2)O) resources in the world. The gypsum ranges from pre-Cambrian to Quaternary in age and occurs in varied geological …

A novel process that includes selective reduction roasting followed by hydrolysis was proposed in this work to recover zinc, and efficiently extract calcium and sulfur from hazardous zinc-rich gypsum residue (ZGR) waste for high-purity of CaCO 3 and sulfur production. The selective reduction behaviors of ZGR during the reduction roasting …

China has the worlds largest proven gypsum (CaSO4.2H (2)O) resources in the world. The gypsum ranges from pre-Cambrian to Quaternary in age and occurs in varied geological environments. The...

The total average Hg emitted due to FGD gypsum resource utilization in China in 2017 was estimated to be 11.42 tons (ranging between 2.15 and 38.35 tons), which accounted for about 23.8 % (ranging ...

The FGD gypsum of Shanxi province of China contained 77.4% of Mn, 25% of total Pb, and 51.8% of Zn as easily-soluble forms showing higher mobility 21. …

In this study, Temperature Programmed Decomposition (TPD) and Sequential Chemical Extraction (SCE) were applied to FGD gypsum to identify the Hg species in it. The FGD gypsum samples were collected from seven coal-fired power plants in China, with Hg concentrations ranging from 0.19 to 3.27μg/g. A series of pure Hg compounds were used …

An abandoned gypsum mine has been discovered beneath the route of a highway construction in Hunan province, south China. Due to the highway construction and operations safety, there is an urgent need for a comprehensive stability analysis of the abandoned mining area. The 3D laser scanning detection technique has been adopted, …

The criteria for MRAC and CLR are crucial to quantitatively evaluate fly ash and gypsum risk from trace elements. In this study, the evaluation criteria for MRAC and CLR (Tables 1 and S8) were set based on trace elements contents in soil quality standard, disposal site characteristics and existing researches (Zhu et al., 2012; Liu et al., 2018; …

Rare earth-bearing gypsum tailings from the fertilizer industry are a potential source for an economically viable and sustainable production of rare earth elements. Large quantities are generated inter alia in Catalão, Brazil, as a by-product in a fertilizer production plant. Hitherto, the gypsum has been used as soil conditioner in agriculture or was dumped. …

Effects of applying flue gas desulfurization gypsum and humic acid on soil physicochemical properties and rapeseed yield of a saline-sodic cropland in the eastern coastal area of China J. Soils Sediments, 16 ( 2016 ), pp. 38 - …

In this study, by regulating gypsum crystal and P species in CaCl 2 –HCl solutions under mild conditions, efficient removal of P impurities (leaching efficiency of 97.78%) and synchronous preparation of high-strength α-CaSO 4 ·0.5H 2 O (α-HH) (compressive strength of 35.2 MPa) from PG were achieved during the phase transition …

gypsum was 18.0 million tons. Synthetic gypsum is mainly produced as a byproduct in flue gas desulfurization (FGD) systems. Calcined gypsum is produced domestically from crude gypsum by heating selenite. In the United States, gypsum is primarily used to manufacture wallboard and plaster for homes, offices, and commercial buildings.

Extraction in 10% NaCl, 50% H 2 SO 4 with pre-concentration using a C18 column: 45: 40: Signal to noise ratio of 3:1 (Almeida et al., 2016; Eiden et al., 1997) ... China. It was stated that Hg was introduced to the study area via contaminated irrigation water, with Hg bound to particulate matter. For natural unfarmed soils, positive ...

"Shigao" is one of the Chinese mineral drugs, derived from calcium sulfate dihydrate (Gypsum, CaSO 4 ×2H 2 0), which has been used as antipyretic for heat in the lung with high fever and dire thirst In general, Japanese Kampo or Chinese medical doctors have made allowance for the amount of gypsum according to symptom complex of patients …

The life cycle of gypsum plasterboard typically begins with the extraction and processing of raw materials, continues with the manufacture and use of the plasterboard, and then reaches end-of-life (EoL) that involves either landfilling, recycling or other forms of recovery (Fig. 1).These life cycle processes are described in the following Sections 2.1–2.4.

The results reveal that calcium sulfoaluminate–belite cement can be produced by burning a raw mixture contains in weight percent (25% kaolin, 20% gypsum and 55% marble sludge waste) at firing ...

Heavy metal-containing gypsum is a widespread hazardous waste. In this work, H + was found to be the most essential factor of the mineralizers in hydrothermal treatment to completely (≥99.8%) extract Cr(VI) from gypsum waste to the supernatant, where the significant growth (from several μm to several hundreds of μm) and perfection …

tive sequential extraction method (SSEM) analyzed the chemical speciation of trace elements in FGD gypsum ... (50.1–73.7%) in FGD gypsum of China 24. Other factors a˚ecting the leaching