Simultaneous mineralization of CO2 and recovery of soluble potassium using earth-abundant potassium feldspar

Abstract

CO 2 capture and storage (CCS) is an important strategy in combatting anthropogenic climate change. However, commercial application of the CCS technique is currently hampered by its high energy expenditure and costs. To overcome this issue, CO 2 capture and utilization (CCU) is a promising CO 2 disposal method. We, for the first time, developed a promising method to mineralize CO 2 using earth-abundant potassium feldspar in order to effectively reduce CO 2 emissions. Our experiments demonstrate that, after adding calcium chloride hexahydrate as an additive, the K-feldspar can be transformed to Ca-silicates at 800C, which can easily mineralize CO 2 to form stable calcium carbonate and recover soluble potassium. The conversion of this process reached 84.7%. With further study, the pretreatment temperature can be reduced to 250C using hydrothermal method by adding the solution of triethanolamine (TEA). The highest conversion can be reached 40.1%. The process of simultaneous mineralization of CO 2 and recovery of soluble potassium can be easily implemented in practice and may provide an economically feasible way to tackle global anthropogenic climate change. CCU, mineralization, potassium feldspar, potassium salts, CCS Citation:Xie H P, Wang Y F, Ju Y, et al. Simultaneous mineralization of CO 2 and recovery of soluble potassium using earth-abundant potassium feldspar. Chin Sci Bull, 2013Bull, , 58: 128132, doi: 10.1007 Carbon dioxide (CO 2 ), produced from the combustion of fossil minerals, is considered to be one of the main factors responsible for global climate change. CO 2 emission reduction has become a significant issue of common concern worldwide. CO 2 capture and storage (CCS) is currently considered one of the most effective techniques for reducing emissions, maintaining the current atmospheric CO 2 concentration, and alleviating greenhouse gas effects [1,2]. While a number of countries or regions have carried out field demonstration projects related to CO 2 geological storage to test CCS, wide application of the CCS is mainly hampered by its high costs. To alleviate the associated costs, appropriate strategy should be focused on carbon capture and utilization (CCU) [3][4][5][6]. By CCU, we mean CO 2 being captured and used as raw material to produce high-value products (or related by-products) thereby reducing CO 2 emissions. In industry, one of method of utilization of CO 2 is transforming CO 2 into organic chemicals or polymers. Another method was regenerate methanol and hydrocarbon from CO 2 and H 2 O which can be used as fuel. These two methods confronted the problem of high material cost, high energy consuming and short lifetime of product. Therefore, many people considered that the CCU method can only transforming small amount of CO 2 , which has little effect on reducing the emission of CO 2 , and the CCU cannot be regarded as the main CO 2 disposal method. CO 2 mineralization is a relatively new technology in the field of CO 2 geological sequestration [7]. Compared with

Extraction of potassium from K-feldspar via the CaCl2 calcination route

“…Han et al [33] regarded the high temperature reaction as a cation exchange reaction between potassium ions in the silica-alumina-oxygen network structure of K-feldspar and calcium ions in the calcium chloride melt. Recently, Xie et al [34] and Ye et al [35] proposed a novel approach for the simultaneous extraction of potassium via the calcination of A C C E P T E D M A N U S C R I P T…”

Aqueous carbonation of the potassium-depleted residue from potassium feldspar–CaCl2 calcination for CO2 fixation

“…Our previous studies (Xie et al 2013b;Ye et al 2014) revealed that wollastonite (CaSiO 3 ), pseudowollastonite (Ca 3 Si 3 O 9 ), Cl-mayenite (Ca 12 Al 14 O 32 Cl 2 ), anorthite (CaAl 2 Si 2 O 8 ), and quartz (SiO 2 ) are the main components in the potassium-depleted residue. Theoretically, all the Cabearing phases in the residue can be utilized for CO 2 fixation.…”

Effect of water on carbonation of mineral aerosol surface models of kaolinite: a density functional theory study

“…wollastonite, olivine) in a proper humidity may interact with high-purity CO 2 in a comparatively short time. Additionally, a new framework has been suggested for CO 2 capture and utilization (CCU), under which the captured CO 2 is taken as initial material to gain high-value products thus reducing CO 2 emissions (Xie 2010a, b;Xie et al 2012aXie et al , b, 2013.…”