INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Siqian Zhang,Cheng Zhang,Qiang Wang,Wha-Seung Ahn
A series of ZSM-5 catalysts were synthesized using fly ash from power plants and red mud from aluminum production in different weight ratios. The ZSM-5 was subsequently coimpregnated with Co and Mn and tested for the low-temperature selective catalytic reduction of NOx by NH3 (NH3-SCR). These catalysts were characterized by XRD, N2-adsorption isotherms, SEM, XPS, and H2-TPR. Among all the prepared catalysts, 5 wt % Co 10 wt % Mn/ZSM-5 had shown the best catalytic activity, with 98.8% conversion of NOx and 90.7% selectivity toward N2 at 150 °C. This is comparable to the performance of a similar ZSM-5 catalyst prepared using chemical reagents. The high ratio of Mn4+/(Mn4+ + Mn3+ + Mn2+) in the catalyst improved the NOx conversion, whereas the moderate redox property imparted by Co3+ led to high N2 selectivity. This catalyst also showed strong resistance against poisoning in 100 ppm SO2 and 5% H2O. This work demonstrates that effective NOx removal treatment with high N2 selectivity and sufficient stability for either cement plants or incinerators can be achieved by using a porous catalyst/support material produced from industrial solid wastes.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2025
·
IF 8.4
Xinyao Li,Liangzhong Li,Zhichao Huang,Zhaofeng Chang,Zhuo Tu,Luping Tian,Wei Du,Hao Li,Peng Zhang,Bo Pan
In the research on the preparation of biochar from co-pyrolysis of red mud (RM) and biomass, the synergistic mechanism of immobilizing heavy metals (HMs) and enhancing the stability of biochar is seldom reported. In this study, the effects of different mass ratios of corn stalks (CS) and RM (9:1, 3:1, 2:1, 1:1) and pyrolysis temperatures (300 °C, 450 °C, 600 °C) on the physicochemical properties, carbon stability, HMs speciation, and their potential risks were investigated. Furthermore, the mechanism of the co-pyrolysis process to enhance biochar stability and facilitate transformation of HMs speciation was analyzed. The results showed that co-pyrolysis of CS with RM significantly enhanced biochar's oxidation resistance (I D /I G = 0.61, R 50,biochar = 0.52), and simultaneously increased the stabilized state proportion of Ni, Cr, and Cd that exceed standard limits, thereby reduced the biochar phytotoxicity (GI = 193.20%). During the co-pyrolysis process, the metals and metal minerals in RM catalyzed the cleavage of CS, promoting the formation of condensed aromatic carbon structures in biochar, which adsorbed the free HMs to form organic carbon-metal/metal oxide complexes through coordination, achieving the dual roles of immobilizing HMs and enhancing the stability of biochar. In addition, the formation of large aggregates and the conversion of free HMs into metal oxides are important mechanisms for co-pyrolysis to enhance the biochar stability and HMs immobilization, respectively. This study provides a feasible and promising direction for the synergistic and efficient resource utilization of industrial and agricultural waste.
研究领域:
环境科学
·
土壤修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RESOURCES CONSERVATION AND RECYCLING
·
2024
·
IF 11.2
Hong Yu,Long Liu,Mingxia Liu,Hanquan Zhang,Run Mao
Red mud (RM) and phosphogypsum (PG) are both large-scale industrial solid wastes, which cause waste of resources reserved in them and pose a huge threat to the environment if not treated appropriately. Guide by the concept of “waste control by waste”, the individual and cooperated effect of PG and sodium sulfate (Na 2 SO 4 ) on iron recovering from RM through reductive roasting-magnetic separation process was comparably investigated. Systematical factorial tests verified the advantage of binary additive. An iron concentrate with iron grade and recovery of 89.02 % and 87.46 % was obtained under the optimized conditions. Mechanistic studies demonstrated that iron oxides were converted to metallic iron through reductive roasting, along with which PG was beneficial for the releasing of iron from complex iron-hosting minerals to a certain extent while binary additive was even more efficient for the reducing, decomposing and grain growing processes. This work realizes the simultaneous utilization of both waste resources.
研究领域:
环境科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
Crystals
·
2025
·Vol. 15
·期 2
·180
·
IF 2.4
Junchi Weng,Xiulin Shen,Yixian Yang,Xuejia Zhang,Mengke Fan,Ge Gao,Zeming Guo,Zhenfei Lv,Xiujuan Feng
Due to the lack of effective utilization, fly ash and red mud accumulate in large quantities and cause serious harm to the environment. In this experiment, a low-cost preparation of foamed ceramics was realized by applying the foaming agent addition method using fly ash and red mud. The results indicated that temperature and foaming agent content significantly affected the macrostructure, microstructure, crystalline phases, and properties of the foamed ceramics. Specifically, a formulation comprising 45 wt.% fly ash, 45 wt.% red mud, 10 wt.% clay, and 1 wt.% SiC (addition), sintered at 1210 °C, yielded a compressive strength of 8.2 MPa, a bulk density of 1.17 g/cm3, a water absorption rate of 32.05%, and an apparent porosity of 37.59%. The as-prepared materials demonstrate potential as cost-effective building materials, putting forward an effective approach for the high-value utilization of fly ash and red mud.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Qiannan Wang,Aaron S. Pittman,Yan Cao
Red mud (RM) is a solid waste generated in the aluminum industry after the extraction of alumina oxide; its multiple elements and higher pH value likely pose a severe threat to the environment after treatment. However, RM's higher concentrations of metal components, particularly Fe 2 O 3 and rare earth elements (REEs), render RM promising for catalytic application. Hence, this work showed an efficient high-speed RM to catalyze electrocatalytic nitrate-to-ammonia reduction reaction (NARR). RM calcined at 500 °C (RM-500) exhibited excellent catalytic performance. Faradaic efficiency of ammonia ( FE NH 3 ) in an electrolyte solution containing 1 mol⋅L − 1 NO 3 − achieved a maximum value of 92.3% at −0.8 V ( vs . RHE). Additionally, 24-h cycle testing and post-reaction PXRD and SEM indicated that the RM-500 electrocatalyst is stable during NARR. The RM-500 demonstrated a high FE of NH 3 -to-NO 3 − of 89.7% at 1.85 V ( vs . RHE), showing great potential in the ammonia fuel cells technology and achieving the nitrogen cycle.
研究领域:
环境科学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
·
IF 7.139
Sulong Geng,Zhanguo Zhang,Junjie Li,Jianguo Qian,Jiao Liu,Jian Yu,Guangwen Xu
Catalyst samples for CH 4 decomposition were prepared from red mud (RM) by an acid-leaching neutralization precipitation approach. Water-washing the resultant precipitates multiple times, followed by drying at 105 °C and calcination at 500 °C, resulted in a threshold of residual Na 2 O, equivalent to 96% Na 2 O removal. Drying the precipitate at a higher temperature of 200 °C, followed by repeated water washing, provided a deeper Na 2 O removal of 99% and made the resultant samples more active for the targeted reaction. Subsequently, four catalyst samples with a simulated red mud composition and NaOH contents from 0 to 0.3 wt% were prepared and the catalytic test results revealed that the Na 2 O remaining in the RM-derived catalysts did not only inhibit their activation in CH 4 but also lower their maximal activities for CH 4 decomposition. Finally, two catalysts with the same simulated red mud composition and their Na impregnated respectively on Fe 2 O 3 and a mixture support of Al 2 O 3 -SiO 2 -TiO 2 were prepared and tested to explore the effect of Na distribution on the activation behavior of RM-derived catalysts for CH 4 decomposition. The activity testing results showed that it was the Na residual dispersed on iron oxides in the RM-derived samples to significantly inhibit the activation of CH 4 decomposition.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Qin Liang,Menghan Zhang,Cai Liang,Huichao Chen
The modified red mud was prepared by thermal reduction with coconut shell for Cr(VI) contaminated soil remediation . Significant reduction of Cr(VI) in soil was achieved for the modified red mud with an efficiency up to 100%. The mass ratio of the modified red mud to soil presents the greatest impact on Cr(VI) reduction in soil, followed by pH, and then the soil moisture. Under the conditions of pH = 4%, and 40% water content, the reduction of Cr(VI) in soil reached 99.37%with 10 wt% of the modified red mud (RM1C-T800(1 h)). Based on the X-ray diffraction spectrum, zero valence iron (ZVI) was detected in RM1C-T800(1 h). The characterization analysis showed that the originally tight and porous surface of RM1C-T800(1 h) became loose and flocculation state after the soil remediation . It implied that internal ZVI particles had recombined with Cr and gradually separated from the parent by exposing to the external surface of RM1C-T800(1 h). The decrease of Cr(VI)in soil was probably attributed to the adsorption and reduction of the ZVI in RM1C-T800(1 h) when mixing the Cr(VI) contaminated soil with RM1C-T800(1 h). The work offers an effective strategy for the resource utilization of solid waste and contaminated site remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Yuan Zhang,Yongshuai Wang,Hongyou Cui,Fang Wang,Zhihe Li,Changhua Sun,Yun Jia,Yujiao Xie,Feng Song,Jiangang Wang,Weiming Yi
Co-pyrolysis of biomass with Red Mud was used to boost up the quality of the produced bio-oil and recover iron from Red Mud. The influences of five different biomass species and impregnation pretreatment were investigated. It was found that co-pyrolysis could significantly improve the bio-oil quality, decreasing the acidity from 173.28 to 1.18 mg KOH/g due to the decarboxylation of carboxylic acids into ketones under the catalysis of Red Mud and boosting up the HHV from 20.05 to 31.80 MJ/kg with an energy efficiency of 72.56%. Meanwhile, the soluble alkalinity of Red Mud declined from 65.34 to 5.26 mg HCl/g, which is very crucial to mitigate the harmfulness and perniciousness to the environment. The characterizations of XRD, 57 Fe Mössbauer spectroscopy and XPS confirmed that the weak magnetic Fe 2 O 3 and FeOOH in Red Mud could be completely transformed into stronger magnetic Fe 3 O 4 . For this reason, the magnetic separation iron recovery reached up to 92.25% with iron grade of 66.12%. The findings in the research not only open the avenue for efficient biomass conversion to high quality fuels, but also provide an efficient approach to resourceful utilization of Red Mud.
研究领域:
能源与环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 6
·826
·
IF 4.9
Jiahao Wang,Huali Zhang,Nenghao Wang,Han Mo,Zhen Yang,Yangyang Dong,Qingwei Liu,Xiao Huang,Baoyi Han
The sustainable management of industrial byproducts represents a critical challenge for the aluminum industry. This study developed a cost-effective adsorbent (SA@RM) derived from sodium alginate and red mud for fluoride removal, addressing both solid waste utilization and water purification needs. Systematic adsorption experiments revealed optimal performance under conditions of 15 g/L dosage and pH 5, achieving adsorption equilibrium within 40 min for initial fluoride concentrations of 11.7 mg/L. Notably, the adsorbent demonstrated exceptional cyclic stability, maintaining 54.8% adsorption capacity through three regeneration cycles. The adsorption process followed the Langmuir isotherm model (R2= 0.994) and pseudo-second-order kinetics (R2= 0.975), indicating monolayer chemisorption as the dominant mechanism. Advanced characterization techniques (SEM-EDS, FT-IR, XPS) elucidated three main mechanisms: fluoride complexation with aluminum oxides, ligand exchange with surface hydroxyl groups, and ion exchange with chloride species. This material achieves 92% fluoride removal while valorizing industrial waste, reducing adsorbent production costs by 60–70% compared to conventional materials. The detailed mechanism analysis provides fundamental insights for designing waste-derived adsorbents, offering a practical solution for sustainable industrial development and water treatment applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
·
2019
·
IF 6.395
Wuming Xie,Fengping Zhou,Jingyong Liu,Xiaolin Bi,Zijun Huang,Yuhui Li,Dongdong Chen,Haiyuan Zou,Shuiyu Sun
A large amounts of red mud (RM) and spent pot lining (SPL) produced during aluminum extraction and electrolysis are restricting the sustainable development of aluminum industry. In this study, an integrated route for synergistic reutilization of RM and SPL was proposed to deal with this dilemma. To improve the recovery efficiency of metallic Fe, Si and Al were firstly extracted from RM to synthesize 4A-zeolite. Afterwards, reductive roasting process was employed for iron recovery using SPL as reducing agent. Metallic Fe obtained from the reductive roasting were collected by wet magnetic separation to yield valuable iron concentrate from nonmagnetic residues. Thermodynamic studies using Factsage 7.1 software were implemented to determine the transformation of mineral phases, and orthogonal design experiments containing various parameters like SPL blend ratio, temperature, and retention time were investigated to optimize the conditions. The reductive process performed at blend ratio of 7 wt%, temperatures of 900 °C and 240 min retention time under N 2 atmosphere induced higher conversion yield of metallic Fe (88.84 wt%). Soluble fluorides in SPL resulted in its hazardous properties, but the formation of cuspidine (Ca 4 Si 2 F 2 O 7 ) in nonmagnetic residues suggested that the route not only reutilized valuable components, but also stabilized the hazardous element.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
Minerals
·
2023
·Vol. 13
·期 3
·452
·
IF 2.5
Rui Chen,Lin Shi,Haoyong Huang,Jie Yuan
Red mud, which could cause numerous problems to the environment, is a hazardous waste generated from the alumina smelting industry. In general, the storage and harmless utilization of red mud are hard to implement due to its fine particle size and high alkalinity. This study put forward a novel process to separate iron (MgFe2O4) and alumina (Al2O3) in red mud by a magnetization sintering method. The magnesium oxide was added to transform the nonmagnetic Fe2O3into magnetic MgFe2O4to achieve physical separation of iron-bearing minerals, and the alumina-bearing minerals were converted into dissoluble NaAlO2minerals in a one-step reaction. The atmospheric pressure leaching process was adopted in this study for alumina resource recovery. To achieve clean alumina production, the silicate in the leaching solution was removed by adding the slightly soluble CaSO4, and the entire process becomes clean and harmless. The feasibility of the process was verified by thermodynamic analysis, and a series of experiments were performed to detect the optimum MgO/(Fe2O3+ MgO) ratio and the calcining and leaching conditions. The morphological and mineralogical characteristics of modified red mud, leaching red mud, and magnetic separation product were studied by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS). It was observed that under the optimal conditions with MgO/(Fe2O3+ MgO) of 14.89% to recover iron and aluminum, the corresponding recovery rates were 67.54% and 73.01% respectively, and the iron grade was 30.46%. The EDS results showed that the obtained Mg/Fe ratio of the magnetic separation product was 0.4677–0.528, which is slightly different from that of the standard MgFe2O4at 0.5. This new method can promote the development of comprehensive utilization of red mud and iron production.Keywords:red mud;harmless utilization;mineralogical analysis;MgFe2O4;leaching parameter
研究领域:
冶金工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xinyue Liu,Yongyu Ren,Zengqi Zhang,Xiaoming Liu,Yaguang Wang
The ammonia nitrogen in electrolytic manganese residue (EMR) is easily transferred to water source, polluting the environment and endangering biological health. In this study, the ammonia nitrogen in EMR is removed by slaked lime, carbide slag (CS) and red mud (RM). The removal of ammonia nitrogen is influenced by the liquid–solid ratio, stirring time, and additives dosage. The removal efficiency of ammonia nitrogen of EMR pretreated with 7.4 % fresh CS for 15 min can reach 98.5 % when the liquid–solid ratio is 1.50. Under the synergistic effect of CS and RM, the ammonia nitrogen in EMR is quickly removed within 15 min, and the removal efficiency of ammonia nitrogen reaches 98.2 %. It is feasible to replace slaked lime with CS and RM to achieve the removal of ammonia nitrogen in EMR. Struvite has high quantity and good purity when the molar ratio of N, P and Mg is 1:1.6:1.6 and pH = 8.0. The remaining EMR after removal of ammonia nitrogen, blast furnace slag, Portland cement and aggregates was used as raw materials to prepare nonsintered bricks (NSB). The NSB according to the optimal formula after curing for 7 days had no free ammonia nitrogen detected. This study provided a new way to remove ammonium nitrogen in EMR by CS and RM, and demonstrated a solution to prepare struvite and nonsintered bricks.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）