Developing high-activity and low-cost desulfurizers is crucial for treating the steel industry low-temperature and highly volatile low-sulfur flue gas. This study proposes a simple and effective additive engineering strategy to convert traditional quicklime into Ca(OH) 2 desulfurizer with high activity via synergistic modification with triethanolamine (TEA), diethylene glycol (DEG), and sodium silicate (Na 2 SiO 3 ). The optimized Ca@TDS has a highly porous microstructure, characterized by a specific surface area as high as 42.19 m 2 /g, and pore volume reaching 0.186 cm 3 /g. It exhibited an elevated sulfur capacity at 37.97 mg/g, with breakthrough time extended to 93.8 min at 100°C, and excellent adaptability under high SO 2 concentrations and CO 2 -containing atmospheres. Comprehensive characterization and kinetic models indicated that the synergistic effect of additives enhanced pore connectivity, promoted internal diffusion, and suppressed surface carbonate deposition. This study also successfully employed 10 tons of industrial products Ind-Ca@TDS to control SO 2 emissions below the ultra-low standard of 35 mg/m 3 in the steel plant pilot test, which fully verified the scalability and industrial feasibility of the method. This work provided an expandable and cost-effective way for the production of high specific surface Ca(OH) 2 , providing practical reference for the development of dry low-temperature FGD technology in the steel industry.
Sulfadiazine (SDZ), a type of antibiotics with refractory and high-mobile characteristics, can accumulate and be detected out in aquatic ecosystems all over the world. SDZ can be destroyed by ozonation, but the degradation effect is easily and negatively affected by carbonate ions (CO 3 2- ) which be eliminated by introduction of Ca 2+ in ozonation systems. Experimental results manifested that the maximum removal rate of 100 % and 94.15 % corresponding to SDZ and chemical oxygen demand (COD) were achieved under the optimum Ca(OH) 2 addition without pH adjustment. In addition, the presence of Cl - and humic acid inhibited the SDZ degradation to some extent. It could be found that Ca 2+ and OH - jointly played great roles in increased oxidation of ozonation. For one thing, quenching effect of CO 3 2- on •OH was eliminated through combination of Ca 2+ and CO 3 2- and low molecular intermediate forming insoluble precipitates. For another, OH - caused alkaline condition which was instrumental in existence of •OH. Moreover, successive addition of Ca(OH) 2 was proposed and proved to be feasible to elevate the •OH generation and oxidizing ability in O 3 /Ca(OH) 2 system. Ultimately, the three potential degradation pathways of SDZ were speculated basing on density function theory (DFT) calculations and identification of several intermediate products. Overall, this study provided promising insights for promotion of antibiotics removal and ozonation efficiency by alleviating the inhibitory effect of carbonate ions in aqueous environment.
危险品化学品经营许可证（带存储）