Mineral carbonation of red gypsum via pH-swing process: Effect of CO2 pressure on the efficiency and products characteristics

Amin Azdarpour, Mohammad Asadullah, Erfan Mohammadian, Radzuan Junin, Hossein Hamidi, Muhammad Manan, Ahmad Rafizan Mohamad Daud

Research output: Contribution to journalArticle

35 Citations (Scopus)

Abstract

The objective of this study was to investigate the feasibility of indirect carbonation of red gypsum through pH swing process. The effect of CO2 pressure as one of the major controlling parameters in carbonation process was investigated in details. The dissolution of red gypsum was performed using 2 M H2SO4 at 70 °C for 60 min reaction time. The pH was regulated using NH4OH, which also precipitated out the impurities from the solution. Finally, the calcium rich solution was poured in an autoclave reactor and CO2 was injected into the reactor for carbonate precipitation. The experimental results showed that the Fe, the main impurity can be effectively separated prior to carbonation stage (92–95%). At low pH the Fe was separated while at high pH Ca was precipitated as carbonate. The carbonation efficiency was directly affected by the CO2 pressure and the maximum efficiency (100%) was achieved when 8 bar CO2 pressure was used. In addition, carbonation experiments resulted in CaCO3 production in the form of calcite, aragonite, and vaterite with 98% purity.
Original languageEnglish
Pages (from-to)425-436
Number of pages12
JournalChemical Engineering Journal
Volume264
Early online date1 Dec 2014
DOIs
Publication statusPublished - 15 Mar 2015

Keywords

  • carbon capture and storage
  • mineral carbonation
  • pH swing
  • calcium carbonate
  • red gypsum

Fingerprint Dive into the research topics of 'Mineral carbonation of red gypsum via pH-swing process: Effect of CO2 pressure on the efficiency and products characteristics'. Together they form a unique fingerprint.

  • Cite this