Mechanistic study on the promotion of Ca2+ leaching in steel slag through high-temperature solid waste modification.

Indirect carbonation of steel slag is an effective method for CO2 storage, reducing emissions, and promoting cleaner production in the steel industry. However, challenges remain, such as low Ca2+ leaching rates and slag management complexities arising from variations in mineral compositions. To address this, a high-temperature modification process is proposed to alter the mineral composition and facilitate the synergistic utilization of calcium and iron. This study delves into the effects of various solid waste modifications on the leaching of Ca2+ and the total iron content within steel slag. Results show that high-basicity modified slag forms Ca2(Al, Fe)2O5, reducing calcium leaching. Low-alkalinity modified slag produces calcium-rich aluminum minerals and also reduces the leaching of Ca2+ ions. At a basicity of 2.5, coal gangue, fly ash, and blast slag achieve maximum Ca2+ leaching rates of 88.93%, 89.46%, and 90.17%, respectively, with corresponding total iron contents of 41.46%, 37.72%, and 35.29%. Upgraded coal gangue exhibits a 50.02% increase in calcium leaching and a 15.58% increase in total iron content compared to the original slag. This enhances CO2 fixation and iron resource utilization. Overall, the proposed indirect carbonation and iron enrichment modification offer a novel approach for the resource utilization and environmental stability of steel slag.

Comparison of 8spheres polyvinyl alcohol microsphere and gelatin sponge particle efficacy for transcatheter arterial chemoembolization in stages A to B patients with hepatocellular carcinoma.

Purpose: This study aimed to compare the clinical efficacy and prognostic analysis results of 8spheres polyvinyl alcohol (PVA) microspheres (8SM) with gelatin sponge (GS) particles for transcatheter arterial chemoembolization (TACE) in patients with stages A-B hepatocellular carcinoma (HCC). Methods: Data were collected from 172 patients who underwent TACE at Harbin Medical University Cancer Hospital from January 2014 to July 2020. Patients were divided into two groups: TACE group using 8SM plus lipiodol (8spheres PVA group, N = 89) and TACE group using GS particles plus lipiodol (the GS group, N = 83). Subsequently, we compared the liver function, blood count, alpha-fetoprotein (AFP), and other parameters of patients in each group before and after interventional embolization. We also calculated the patient's progression-free survival and overall survival in these groups. Results: The postoperative liver function indices, such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in the 8spheres PVA group, were worse than in the GS group. The postoperative median survival time was 19 ± 3.06 months and no significant difference in survival time was observed in GS group (26 ± 3.19 months) (P = 0.509). Multivariate analysis showed that targeted therapy (P = 0.051), maximum tumor diameter <5 cm (P = 0.018), age ≥60 years (P = 0.018), and AFP <120.5 µg/L (P = 0.007) significantly improved the overall survival rate of patients. Conclusion: Postoperative liver function indices of patients with HCC treated with GS particles were better than those treated with 8SM; thus, GS particles are more suitable for patients with poor liver function.

Research status and future challenge for CO2 sequestration by mineral carbonation strategy using iron and steel slag.

Mineral carbonation can simultaneously realize the effective treatment of CO2 and iron and steel slag; thus, it is of great significance for the low carbon and sustainable development of iron and steel industry. In this article, the researches of mineral carbonation process using iron and steel slag as feedstock are reviewed, and the carbonation reaction mechanism and the parameters affecting the reaction rate and carbonation degree are analyzed. Furthermore, the effect of different enforcement approaches, such as ultrasonic enhancement, mixed calcination, microbial enhancement, and cyclic coprocessing on mineral carbonation reaction, is introduced. The additional effects of mineral carbonation, such as solving the problem of poor volume stability of steel slag, weakening the leaching of heavy metal ions, and reducing the pH of the leachate, are also illustrated. Moreover, issues related to mineral carbonation technology that should be emphasized upon soon, such as the production of valuable products, use of industrial wastewater, aqueous phase recycling use, multiparameter coupling analysis, and research on the properties of carbonation residues, are also discussed, which contribute some perspectives to the future development of mineral carbonation of iron and steel slag.