Soda Ash Production with Low Energy Consumption Using Proton Cycled Membrane Electrolysis

Abstract

Soda ash, as one of the most important chemicals, is mainly manufactured by the Solvay process. However, the Solvay process consumes energy at a rate of up to 9.7–13.6 GJ/ton Na2CO3. Here, we present an energy-saving method to produce soda ash in a proton cycled membrane electrolysis (PCME) process. After forming H+ and OH– at the anode and cathode in electrolysis process, respectively. The H+-containing solution is used to react with CaCO3 to obtain pure CO2, which is absorbed by the OH–-containing catholyte to generate soda ash with a purity of 99.2%. Our experiments found that the voltage required for PCME was 0.538–0.765 V at 10 mA/cm2, and the average current efficiency was up to 93.7%. Therefore, the energy consumption in soda ash production can be reduced to 5.32 GJ/ton soda ash, a decrease of about 60.9% compared with the Solvay process.

Unraveling a Sustainable Process for the Production of High-Strength α-Gypsum Using Soda Residues and H2SO4

“…Chloride salt solutions such as CaCl 2 , MgCl 2 , KCl, AlCl 3 , ZnCl 2 , and BaCl 2 are all desirable candidates to foster the phase transition process from DH to HH. ,,− In this experiment, a solution containing 25 wt % CaCl 2 , 3 wt % MgCl 2 , 1% KCl, along with 0.125‰ succinic acid and 0.0625‰ ethylenediaminetetraacetic acid disodium salt dihydrate (C 10 H 14 N 2 Na 2 O 8 , EDTA-2Na) was added to the soda residue slurry under atmospheric pressure. The transition process was controlled at 368 K, solids were filtered at each hour up to 6 h, and, thus, six samples were taken for XRD analysis.…”

“…These rules forbid stockpiling soda residues after clarifying the wasted liquor, forming “white walls” overtime or contaminating nearby waterways if flooded. Instead of relocating them site to site, innovations for comprehensive utilization of soda waste need to be result-driven …”

“…Calcium sulfate is often processed and used as building materials for the construction of false ceilings, road sub-bases, fire resistants, etc. − It was projected that the global gypsum demand is expected to grow for CAGR by 10% on average, to reach 870 Mt by 2026. As known, CaSO 4 is associated with two hydrate forms: α-HH and β-HH; ,, the dehydration temperature and the transformation kinetics of CaSO 4 ·2H 2 O (dihydrate, DH) directly influence the polymorph formed, provided that CaSO 4 ·0.5H 2 O (α-HH) demonstrates greater value-added utilization due to higher mechanical strength than β-HH . Two of the most successful commercialized production processes for α-HH are the patented SICOWA-ProMineral autoclaving process and the Omega process .…”

Decarbonisation of calcium carbonate at atmospheric temperatures and pressures, with simultaneous CO2 capture, through production of sodium carbonate

“…Up to 1.43 kg of Na 2 CO 3 is produced alongside every kg of Ca(OH) 2 ; if the conventional processes are considered, the production of these combined can demand 23 648 kJ (13 600 kJ per kg Na 2 CO 3 Â 1.43 kg Na 2 CO 3 + 4200 kJ per kg Ca(OH) 2 Â 1.00 kg Ca(OH) 2 ). 24,25 Using the technology presented in this work, the Fig. 4 Thermogravimetric and derivative thermogravimetric analyses of the Samples 1L (solid lines) and 5L (dashed lines).…”

Prospects for the use of liquid waste from the production of sodium carbonate as a coolant based on the ternary system CaCl2-K2Cr2O7-H2O

“…Таблица 1. Состав исходной смеси компонентов, равновесной жидкой и твердой фаз [13,14]. Высокое содержание бихромат-иона в твердой фазе говорит о возможности образования твердых растворов или двойных соединений на основе системы СaСr2О7 -К2Сr2О7.…”