Enhancement of aragonite mineralization with a chelating agent for CO2 storage and utilization at low to moderate temperatures

Abstract

Among the CaCO3 polymorphs, aragonite demonstrates a better performance as a filler material in the paper and plastic industries. Despite being ideal from the environmental protection perspective, the production of aragonite particles via CO2 mineralization of rocks is hindered by the difficulty in achieving high production efficiencies and purities, which, however, can be mitigated by exploiting the potential ability of chelating agents on metal ions extraction and carbonation controlling. Herein, chelating agent N,N-dicarboxymethyl glutamic acid (GLDA) was used to enhance the extraction of Ca from calcium silicate and facilitate the production of aragonite particles during the subsequent Ca carbonation. CO2 mineralization was promoted in the presence of 0.01–0.1 M GLDA at ≤ 80 °C, with the maximal CaCO3 production efficiency reached 308 g/kg of calcium silicate in 60 min using 0.03 M GLDA, which is 15.5 times higher than that without GLDA. In addition, GLDA showed excellent effects on promoting aragonite precipitation, e.g., the content of aragonite was only 5.1% in the absence of GLDA at 50 °C, whereas highly pure (> 90%, increased by a factor of 18) and morphologically uniform aragonite was obtained using ≥ 0.05 M GLDA under identical conditions. Aragonite particle morphologies could also be controlled by varying the GLDA concentration and carbonation temperature. This study proposed a carbon-negative aragonite production method, demonstrated the possibility of enhanced and controlled aragonite particle production during the CO2 mineralization of calcium silicates in the presence of chelating agents.

NaHCO3 as a carrier of CO2 and its enhancement effect on mineralization during hydrothermal alteration of basalt

“…The preferred dissolution of plagioclase over clinopyroxene from basalt was consistent with the result of Nesbitt and Wilson (1992) (Nesbitt and Wilson, 1992). Calcite is the main product of basalt carbonation, as evidenced by the characteristic calcite peak at 29.6 °(2θ, CuKα) (Wang et al, 2021) after reaction of basalt in NaHCO 3 solution, and the calcite peak showed higher intensity when the reaction time increased from 5 to 10 days, suggesting an increase in calcite concentration in the reacted sample. Meanwhile, peaks of analcime (e.g., 15.8 °, 26.0 °), a Na-Al silicate with the general chemical formula of NaAlSi 2 O 6 •H₂O, and smectite (in the range of 6.3 °-8.0 °), a clay mineral contains Mg, Fe, Si, as well as Al (Yamashita et al, 2019), were also detected.…”

“…The urgent need to reduce the amount of carbon dioxide (CO 2 ) for creating a carbon neutral society has driven the development of various CO 2 capture, utilization, and storage (CCUS) techniques (Voigt et al, 2021). Among the CCUS techniques, mineralization of CO 2 to water-insoluble carbonates using Mg or Ca-rich rocks such as basalt (Goldberg et al, 2008;Okoko and Olaka, 2021), peridotite (Oelkers et al, 2008) and wollastonite (Wang et al, 2021) is a promising method for large-scale and long-term CO 2 storage with low risk of releasing stored CO 2 into the atmosphere (Zhao et al, 2015) and probably a relative acceptable cost (National Academies of Sciences, 2018; Kelemen et al, 2019). Basalt is one of the optimum rocks for CO 2 storage because of its chemical composition, abundant distribution and easy availability.…”

New Chemical Systems for the Removal of Calcareous Encrustations on Monumental Fountains: A Case Study of the Nymphaeum of Cerriglio

“…However, Ethylenediaminetetraacetic acid (EDTA) is widely used in several applications, and its persistence in aquatic systems is leading to serious environmental consequences. GLDA salts are biodegradable candidates that can replace EDTA [30,31]. They showed a strong capability of chelating calcium ions at pH values in a certain range [32,33].…”