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In the pursuit of shifting technology towards sustainable, environmentally benign processes, post-combustion carbon capture technology is recognised to be a timely mitigation option. This paper presents the development of a novel sodium carbonate-based post combustion carbon capture process utilising the carbonate mineral trona (trisodium hydrogendicarbonate dihydrate) as main sorbent feedstock source. The energy penalty, the fraction of energy sacrificed to capture CO 2 relative to the net energy produced serves as main performance indicator. Investigations on the correlative relationship between energy penalty as a function of capture efficiency are carried out by retrofitting the process to a 600 M W reference coal-fired power plant. The energy penalty of the global system features a distinct local minimum of 3.99 %, corresponding to a CO 2 capture efficiency of 90.00 % and a CO 2 outlet purity of 99.90%. The Specific Primary Energy Consumption for CO 2 Avoided (SPECCA) index corresponding to this minimum is evaluated to be SPECCA = 0.514 M J kg CO −1 2 . Sensitivity analyses on the effect of increasingly high SO 2 flue gas volume fractions y SO 2 show that the capture efficiency is virtually unimpaired for calcination temperatures of 190 ≤ T ≤ 280 • C and y SO 2 ranging from 0.50 to 0.70 %. Whilst commercially available CO 2 capture technology is energy intense and prone to sorbent degradation, the process developed retains high capture efficiencies of calcium oxide-based looping cycles at low operating temperatures and eliminates the predisposition of amine-based sorbents utilised in scrubbing capture schemes to deplete due to the presence of SO 2 in the inlet flue gas stream. It can be concluded that sodium carbonate based post-combustion capture processes are a competitive alternative to existing CO 2 capture technologies.

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This study explored the application of mineral carbonation products in the form of monohydrocalcite (MHC) as a Portland cement additive. This work studied the effect of adding monohydrocalcite on the microstructural change in cement hydration. We investigated the hydration and microstructure development of MHC−cement at different aging times and different MHC mass % values. Chemical composition changes over time were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The hydration behaviors of MHC blended with cement were monitored using thermogravimetric analysis and differential thermal analysis (TGA−DTA). The results indicated that the role of MHC in the hydrated cement was enhancing the cement hydration process with may increase the long term strength gain. We also discovered the effect of MHC in term of the long-term chemical reaction and forming the new phase formation of tilleyite in the hydrated MHC cement at long curing ages that was not present in the ordinary Portland cement (OPC) system.

The authorship has changed: Wanawan Pragot regrettably published the work that she carried out during her Ph.D. at the University of Aberdeen under the supervision of Waheed Afzal where this work had been assisted by (then) post-doc Ara Carballo-Meilan and (then Ph.D. student) Lewis McDonald. Wanawan Pragot regrets her action and wants to correct it. She notes that Chaiwat Photong helped her in proofreading the manuscript before she submitted. We believe that the contribution of Chaiwat Photong does not merit being the first author. The revised order and new additions reflect the contributions.The Acknowledgment and Author contributions have also been revised as given here.