Experimental Data on Solubility of the Two Calcium Sulfates Gypsum and Anhydrite in Aqueous Solutions

Abstract

Calcium sulfate exists in three forms, namely dihydrate or gypsum (CaSO4·2H2O), anhydrite (CaSO4), and hemihydrate or bassanite (CaSO4·0.5H2O) depending on temperature, pressure, pH, and formation conditions. The formation of calcium sulfates occurs widely in nature and in many engineering settings. Herein, a dataset containing the experimental solubility data of calcium sulfate minerals, i.e., gypsum and anhydrite, in aqueous solutions is presented. The compiled dataset contains calcium sulfates solubility values extracted from 42 papers published between 1906 and 2019. The dataset can be used for various scientific and engineering purposes such as environmental applications (e.g., gas treatment, wastewater treatment, and chemical disposal), geotechnical applications (e.g., clay-sulfate rock swelling), separation processes (e.g., crystallization, extractive distillation, and seawater desalination), and electrochemical processes (e.g., corrosion and electrolysis).

Initial Laboratory Measurements Probing Hydrogen Interactions with Eagle Ford Shale and Pyrite: Potential Implications for Subsurface Hydrogen Storage

“…Pure gypsum has a solubility of 2041 mg/L in water at 25 °C, which is similar to the ranges observed in this study . Taherdangkoo et al reported that the solubility of gypsum decreases with an increase in temperature; thus, elevated temperatures and pressures in this work will likely decrease the solubility of gypsum . Arcos et al further discussed the solubility of gypsum in groundwater with a log K value at 25 °C of −4.85 in nuclear waste applications …”

“…37 Taherdangkoo et al reported that the solubility of gypsum decreases with an increase in temperature; thus, elevated temperatures and pressures in this work will likely decrease the solubility of gypsum. 38 Arcos et al further discussed the solubility of gypsum in groundwater with a log K value at 25 °C of −4.85 in nuclear waste applications. 39 It is unlikely that the pyrite framboid clusters within the Eagle Ford Shale samples reacted significantly with H 2 , even though pure pyrite showed reactivity with H 2 gas alone (see eq 1) (vide supra).…”

Optimizing the Sulfates Content of Cement Using Neural Networks and Uncertainty Analysis

“…During cement grinding, elevated temperatures partially dehydrate gypsum into hemihydrate form or bassanite (CaSO 4 .0.5H 2 O or Cs.0.5H) [2]. Copeland et al [3] and a recent systematic review [4] clarify the solubility of the three phases of CaSO 4 .…”