Decoupling type carbon dioxide mineralization membrane electrolysis system for producing high-purity carbonate

Abstract

The invention belongs to the technical field of electrochemistry, and particularly relates to a decoupling type CO2 mineralization membrane electrolysis system for producing high-purity carbonate. According to the system, energy is supplied through an external power supply, the pH environment of a solution is changed through an electrochemical proton coupled electron transfer (PCET) reaction, high-concentration acid is extracted and purified through an efficient extraction separating agent so as to treat natural minerals or alkali liquor solid waste, and organic PCET reactants are reduced and regenerated through a non-electrochemical reaction, so that low-cost, high-efficiency and energy-saving effects are achieved. The invention relates to a stable operation process of a CO2 mineralization membrane electrolysis system with high resource conversion rate. According to the invention, the organic PCET reactant is adopted at the anode, so that the use of an H2 gas diffusion electrode is avoided; and CO2 is absorbed while hydrogen evolution reaction occurs on the cathode side, so that the influence of O2 and dissolved oxygen in CO2 on an anode organic PCET reactant is thoroughly avoided. And meanwhile, H2 generated by the cathode can be used as a reducing agent to realize reduction regeneration of an organic PCET reactant, so that continuous and stable operation of the CO2 mineralization membrane electrolysis system is realized.

Description

technical field [0001] The invention belongs to the technical field of electrochemistry, and specifically relates to a decoupled CO 2 Mineralized membrane electrolysis system. Background technique [0002] CO 2 Mineralization refers to the CO 2 The process of transforming into inorganic carbonate is CO 2 One of the key technologies for emission reduction utilization (CCU). At present, many domestic and foreign researches have carried out the use of bulk calcium and magnesium salt ores (serpentine, olivine, wollastonite) or solid waste (calcium carbide slag, steel slag, red mud) etc. 2 mineralization studies. [0003] However, the current CO 2 Mineralization utilization technologies generally face the technical problems of high energy consumption for mineralization reaction activation, high cost, and low economic value of products, which limit the CO 2 Feasibility of large-scale application of mineralization technology. However, using the proton cycle driven technolog...

AI Technical Summary

Problems solved by technology

Among them, using cycle H 2 A major difficulty is that the H 2 The electrochemical oxidation reaction requires the use of gas diffusion electrodes, and the difficult-to-control three-phase reaction interface will easily cause the electrode to "flood" and cause the electrode failure reaction to be difficult to operate stably.

And adopting a big core difficult problem of organic PCET reactant is that O 2 Impact on System Stability

Especially absorbing CO 2 on the cathode side, a small amount of O 2 The presence of (gas oxygen or dissolved oxygen) will cause the rapid attenuation of electrochemical proton-coupled electron transfer reactants, making it difficult for the system to operate stably

In addition, CO 2 The mineralized membrane electrolysis system needs to use acidic anolyte to directly treat natural minerals or alkaline solid waste. If PCET reactants are used as electrochemical redox carriers, it will cause irreversible loss of organic PCET reactants and increase treatment costs.

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