Petroleum Reservoir Evaluation and Development ›› 2022, Vol. 12 ›› Issue (5): 777-783.doi: 10.13809/j.cnki.cn32-1825/te.2022.05.009

• Methodological and Theory • Previous Articles     Next Articles

Experimental study on reaction of chlorite with CO2 aqueous solution

DENG Jiasheng1(),WANG Ziyi2,HE Wangda1,PENG Dongyu3(),YU Bo1,TANG Hongming2   

  1. 1. Baikouquan Oil Production Plant of CNPC Xinjiang Oilfield Company, Karamay, Xinjiang 834000, China
    2. Southwest Petroleum University, Chengdu, Sichuan 610500, China
    3. Zhanjiang Branch of CNOOC(China), Zhanjiang, Guangdong 524057, China
  • Received:2021-11-09 Online:2022-10-26 Published:2022-09-27
  • Contact: PENG Dongyu;


During the reaction between CO2 and rocks, there is a synergistic/coupling effect among minerals because the rocks contain quartz, potassium feldspar, albite and other components, which promotes or inhibits the reaction process to a certain extent. The chlorite is an important clay mineral of sedimentary rocks. In order to clarify the chemical behavior and change process of the chlorite in the CO2 aqueous solution, the state of chlorite reacting with CO2 respectively for 7 and 30 days at 10 MPa and 60 ℃ are systematically evaluated by means of XRD(X-Ray Diffraction), XRF(X-Ray Fluorescence), ICP(Inductively Coupled Plasma), and SEM(Scanning Electron Microscopy), focusing on the comparison of the change of the solid elements, the crystal structure and the ion concentration in the reaction solution before and after chlorite powder reaction. Combined with the structural characteristics of chlorite, the mechanism of chlorite change is clarified. The results show that the concentrations of Ca2+, Mg2+ and Al3+ in the liquid phase firstly increase and then decrease after the reaction of the chlorite with CO2. The concentration of Si4+ firstly increases and then is stabilized. The crystal planes corresponding to chlorite d(002) and d (004) peaks in the solid phase are destroyed after the reaction, and the mass ratio of Si and Al in the solid element increase from 4.82 to 5.39. Under the acidic conditions, hydroxyl groups in brucite flakes are easier to combine with H+ and release cations such as Fe2+, Mg2+, Al3+, etc. Because the brucite octahedron is more prone to ion exchange than silica tetrahedron and alumina octahedron, Mg, Al, Fe and other elements in brucite flakes are dissolved before Si and Al in silica tetrahedron and alumina octahedron.

Key words: chlorite, CO2 flooding, XRD analysis, element analysis, ion concentration

CLC Number: 

  • TE357