Dehydroxylation of serpentine minerals: Implications for mineral carbonation

Abstract

This review examines studies on the dehydroxylation of serpentine minerals published in the open literature from 1945 to 2013, with brief description of earlier work.Presently, the energy cost and technological complications, required to amorphise serpentine minerals by dehydroxylation, prevent their large-scale application for sequestering of CO 2 . The focus of the review is on thermal dehydroxylation, although mechanical dehydroxylation by grinding and shock, as well as thermomechanical dehydroxylation are also covered. We discuss the chemical and physical transformations involving the proposed mechanisms, thermal stability, reaction kinetics, the formation of intermediates and products, associated heat requirements, factors that influence the reaction, as well as associated enhancements in both dissolution and carbonation. The primary factor controlling the availability of Mg for either extraction or carbonation is structural disorder. The review demonstrates that activation processes must avoid recrystallisation of disordered phases to fosterite and enstatite, and minimise the partial pressure of water vapour that engenders reverse reaction.

Dioctahedral Phyllosilicates Versus Zeolites and Carbonates Versus Zeolites Competitions as Constraints to Understanding Early Mars Alteration Conditions

“…This band could be linked to (Fe,Mg) 3 ‐OH liaisons of Fe‐rich trioctahedral chlorite (King & Clark, ). Note that this XRD and NIR behavior could not be attributed to serpentine (while the XRD peak position could correspond to serpentine) because its dehydration temperature is at 600°C (Dlugogorski & Balucan, ). Therefore, from the XRD behavior and the NIR analysis, this clay mineral is a Fe‐rich chlorite/smectite MLM with a low amount of smectite layers.…”

Alkali-Activated Binder Based on Milled Antigorite

“…It was found that MA caused this peak to shift to a lower temperature region. The exothermic peak at 830 • C corresponds to crystallisation of forsterite and/or enstatite [7,11,12]. Its position did not change with increased milling time.…”

“…This is mainly due to the fact that achieving the desired binding properties requires the calcination of large 2 of 14 volumes of raw materials within a narrow temperature range (depending on serpentinite composition), with strictly fixed residence. Recently, the increased reactivity of dehydroxylated serpentine minerals has been extensively studied with respect to their aqueous dissolution and carbonation (reviewed in [7,8]). This research has been driven by current interests in the extraction of metals from serpentine, and the reduction of anthropogenic CO 2 emissions.…”

“…This research has been driven by current interests in the extraction of metals from serpentine, and the reduction of anthropogenic CO 2 emissions. Mechanical activation of serpentine and other kinds of pre-treatment can have similar effects as thermal treatment with regards to dehydroxylation and reactivity [7][8][9][10][11][12].…”

Geochemical study of ultramafic rocks from Latowu area of North Kolaka, Southeast Sulawesi and its implication for CO2 sequestration

“…Chemically bound water in serpentine structure may also has an influence in increase of chemical reactivity (Lackner et al, 1995). Dehydroxilation of serpentine may take place at the temperature above 550 o C, leading to produce amorphous material (Dlugogorski and Balucan, 2014).…”