POWDER TECHNOLOGY
·
2024
·
IF 4.5
Xiaoqing Liang,Xinying Zhou,Xiner Lu,Aihua Liu
Exploring the application of slag in methane explosion suppression can contribute to its waste resource utilization. In this study, waste slag was subjected to high-temperature scorching and modified using the sol-gel method. Subsequently, a mechanochemical technology was employed to create a composite powder consisting of KHCO 3 and modified slag. A 20 L explosion ball was also used to assess the features of explosion suppression, and pyrolysis characteristics and explosion products were analyzed to clarify the underlying mechanism. The best explosion suppression was shown by adding 0.1 g/L 40 wt% of KHCO 3 /modified slag composite powder. It reduced P max and (d P /d t ) max by 42.35% and 89.47%, respectively, while extending the time for the flame to reach the edge of the transparent window by a factor of 7.1 in 9.5% methane explosion. The KHCO 3 /modified slag composite powder efficiently suppresses explosions by absorbing heat, creating barriers, and adsorbing and consuming free radicals.
研究领域:
材料科学
·
能源安全
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CEMENT & CONCRETE COMPOSITES
·
2020
·
IF 6.257
Woo Sung Yum,Jung-Il Suh,Dongho Jeon,Jae Eun Oh
This study investigated the effect of calcium formate (CF) on the strength development and microstructure of the CaO-activated ground granulated blast furnace slag (GGBFS) system. The main activator (i.e., CaO) was fixed at 4 wt%, and the GGBFS was replaced with CF at 0, 1, 3, and 5 wt%. The use of CF significantly increased the strength of the binder system by inducing (1) more dissolution of GGBFS, (2) greater C–S–H formation although when CF was used over a certain limit (i.e., 3 wt%), the formation of C–S–H began to be disturbed, and most importantly, (3) an increase in C2AH8 formation. In this study, although the greater formation of C2AH8 was the main cause of the strength enhancement, the C2AH8 phase also likely increased porosity and reduced strength as it was metastable; thus, strength increasing effect and reducing effect likely offset each other; thus, with increasing CF dosage, when the former was more dominant, the strength was enhanced (e.g., up to 3 wt%), but when the latter was larger, the strength enhancement decreased (e.g., at 5 wt%).
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2022
·Vol. 105
·期 9
·5929-5943
·
IF 4.186
Jie Ren,Hongfang Sun,Qun Li,Zhenming Li,Xiaogang Zhang,Yanshuai Wang,Linfei Li,Feng Xing
In this research, the effects of natural seawater (SW) on the properties of alkali-activated slag/fly ash (AASF) are studied. AASF prepared with deionized water is set as the reference mixture. The results showed that the use of natural SW resulted in a prolonged setting time and lower heat release, but no obvious impact on the flowability of AASF specimens. The long-term compressive strength became higher when SW was used, whereas the corresponding flexural strength and fractural toughness turned lower. The use of SW induced the formation of new products that were not identified in the reference mixture, such as Cl–hydrocalumite and gypsum. In addition, it is evidenced that the dissolution of fly ash (FA) particles was significantly delayed with the incorporation of SW. All these results were related to the various ions introduced by the natural SW and their interactions with the alkaline activator as well as the precipitation of salts on slag and FA surfaces or in the matrix.
研究领域:
土木工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
GLASS PHYSICS AND CHEMISTRY
·
2023
·Vol. 49
·期 5
·463-477
·
IF 0.7
Wence Xu,Cao Zhao,Ma Rui,Zhang Yuxuan,Wu Nannan,Ouyang Shunli
Abstract Utilizing mining and metallurgical waste as a resource is one of the effective methods to tackle the issue of solid waste accumulation. In this study, the CaO–MgO–Al 2 O 3 –SiO 2 system glass–ceramics were prepared based on the traditional melt-casting technique using iron ore slag as the main raw material. Investigations were done on how different iron ion concentrations affected glass–ceramics properties. And the migration pattern of iron ions was explored deeply using Raman spectroscopy and FTIR. XRD revealed the crystallization ability of augite and magnetite increasing as the iron ions grew. The combination of vibrating sample magnetometer, electron backscatter diffraction, and MFM techniques indicates that the distribution of magnetite, grain size, and structure are connected to the magnetic performances of glass–ceramics. Glass–ceramics has outstanding magnetic properties and flexural strength. Therefore, it has vast potential for future development in electronic devices, wear-resistant applications, and electromagnetic shielding.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Woo Sung Yum,Jung-Il Suh,Do Hoon Kim,Jae Eun Oh
Recently, the combined use of calcium oxide (CaO) and calcium formate (Ca(HCOO) 2 ) has been proposed as an alternative activator for ground granulated blast furnace slag (GGBFS) (referred to as CaO-Ca(HCOO) 2 -activated GGBFS system). However, this clinker-free binder system produces calcium aluminate hydrate (C 2 AH 8 ), generally leading to the degradation of cementitious binder systems by its conversion to other phases. Thus, in this study, attempts to remove C 2 AH 8 from this system without losing the strength are suggested by the use of two additives (i.e., calcium sulfate (CaSO 4 ) and calcium nitrate (Ca(NO 3 ) 2 ), respectively). Results revealed that the above-mentioned additives completely remove C 2 AH 8 in the initial curing stage via its conversion to ettringite or NO 3 - and NO 2 -AFm, respectively. In addition, the additives reduced the extent of the total shrinkage and the standard deviation of strength results of triplicate samples. However, CaSO 4 exerted a beneficial effect on the strength, while Ca(NO 3 ) 2 exerted a marginal or detrimental effect on the strength. Therefore, this study suggested a new mixture form of an activator, comprising CaO , Ca(HCOO) 2 , and CaSO 4 , to activate GGBFS for maintaining strength without the conversion issue of C 2 AH 8 .
研究领域:
建筑材料学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2021
·
IF 9.297
Zhenhai Xu,Jianming Gao,Yasong Zhao,Shujun Li,Zhaoheng Guo,Xu Luo,Gaofeng Chen
Utilization of high volume ground granulated blast furnace slag (GGBS) to produce cement-based materials (CBMs) meets the requirements of sustainable development. However, high volume GGBS will significantly reduce some properties of CBMs. Incorporation of nanosilica is a potentially feasible approach to solve the problem. In present paper, effects of nanosilica (1 wt%, 2 wt% and 3 wt%) on hydration and microstructure of blended cement incorporating high volume GGBS (80 wt%) have been studied by testing setting time, compressive strength , hydration heat, hydration products and pore structure . Results reveal that nanosilica shortens the initial and final setting time of blended cement by 10.75%–20.56% and 10.45%–23.00%, respectively. Furthermore, nanosilica enhances early hydration heat release rate of cement and GGBS. Meanwhile, nanosilica increases cumulative heat release of blended cement by 23.40%–26.46%. However, nanosilica hinders cement hydration after curing for 7 d. Results of thermal analysis indicate that 80 wt% GGBS significantly reduces the content of chemically bound water, while nanosilica improves the parameter by 1.32%–5.91% at 56 d. Additionally, 80 wt% GGBS increases cumulative porosity by 31.89% at 28 d, but nanosilica decreases cumulative porosity by 3.05% at 28 d. Both high volume GGBS and nanosilica can decrease average pore diameter and enhance microstructure of cement paste . Ultimately, nanosilica increases the 28 d compressive strength by 8.27%–19.23%, which partially compensates for the reduction of compressive strength caused by high volume GGBS. This paper can provide the essential foundation for the theory of nanosilica-modified CBMs with high volume GGBS, help to improve the effective utilization rate of GGBS and realize sustainable development of CBMs.
研究领域:
建筑材料学
·
可持续发展工程
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
·
2024
·
IF 2.2
Fengrong Zhang,Cuilan Zhang,Binghan Zhang,Dandan Han,Longwei Du,Lishun Wu
Blast furnace slag (BFS) is a kind of waste produced in industrial production, as well as a valuable secondary resource. In this paper, layered double hydroxides composites (BFS/LDHs) were prepared by aqueous polymerization, with industrial waste BFS as modifier and magnesium nitrate, aluminium nitrate, and urea as raw materials. BFS/LDHs have been characterized by using scanning electron microscopy (SEM), fourier infrared spectrometer (FT IR), x-ray diffraction (XRD), and the specific surface area analyser (BET). The adsorption of BFS/LDHs on Cu (II) and methylene blue (MB) was investigated by batch experiments. The results showed that the adsorption capacity of BFS/LDHs to Cu (II) is stronger than that of MB. What’s more, the solid concentration effect was found in the process of sorption kinetics and sorption isotherms. The sorption kinetics curves of Cu (II) and MB on BFS/LDHs were well fitted by the quasi-second-order kinetics under different adsorbent concentrations. Langmuir and Freundlich sorption isotherm models were used to analyse the adsorption. It showed that the adsorption conforms to Langmuir and Freundlich’s adsorption isotherm models. The BFS/LDHs composites have good recycling availability in this adsorption process of Cu (II) and MB, the removal capacity of which was reduced by 16.1% and 3.8% after being recycled for six times, respectively. More importantly, BFS/LDHs composites are not only expected to become a sewage treatment agent, but also to solve the problem of industrial waste treatment, which is a win–win strategy.
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
Sustainability
·
2021
·Vol. 13
·期 20
·11144
·
IF 3.251
Wei Zhao,Xiaofeng Huang,Bingji Yan,Shaoyan Hu,Hongwei Guo,Dong Chen
Diopside-based glass-ceramics are successfully produced by recycling blast furnace slag and fluorite tailing with the addition of supplementary elements such as TiO2, Fe2O3and Cr2O3as nucleation agents, using a conventional melting method. The effects of various nucleating agents on the phase components and structure of the prepared glass-ceramics were evaluated by a differential scanning calorimeter, X-ray diffraction and scanning electron microscope–energy disperse spectrometer methods to determine the optimal dosage of nucleating agents. The results show that, in the preparation of diopside-based glass-ceramics, the suitable percentages of blast furnace and fluorite tailing are 55% and 45%, and the recommended composite nucleating agents consist of 1.5% Cr2O3, 2% TiO2and 3% Fe2O3. Heat treatment was conducted at a nucleation temperature of 720 °C and a crystallization temperature of 920 °C, and the nucleation and crystallization durations were 1.0 h and 1.5 h, respectively. Under the abovementioned parameters, the obtained diopside-based glass-ceramics displayed a Vickers hardness of 7.12 GPa, density of 2.95 g·cm−3, water absorption of 0.02%, acid resistance of 0.23% and alkali resistance of 0.02%.Keywords:blast furnace slag;fluorite tailing;diopside;glass-ceramics;nucleating agent
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 17
·4409
·
IF 3.1
Yuxiang Chen,Shengping Wu,Hanhui Huang,Feng Rao,Lang Yang
This study aims to compare the effects of three calcium compounds on the workability, setting time and mechanical properties of red mud (RM)–blast furnace slag (BFS)-based geopolymers. The crystalline phase, hydration process and microstructure of RM-BFS-based geopolymers were characterized by X-ray diffraction (XRD), heat evolution, X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) tests. The results showed that an appropriate amount of calcium compounds can improve the flowability and compressive strength of the geopolymers, but the excessiveness causes a decrease in strength due to rapid hardening. Other than calcium carbonate, both calcium oxide and calcium chloride played important roles in accelerating the setting times of RM-BFS-based geopolymers. The acceleration in the setting times of geopolymers could be attributed to the calcium hydroxide produced by the dissolution of the calcium compounds, which also provides nucleation sites for the geopolymerization reaction. This study gives new insights into the effect of calcium on the setting times and mechanical properties of geopolymers in the geopolymerization process.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2021
·
IF 6.141
Jie Ren,Hongfang Sun,Kun Cao,Zhili Ren,Bo Zhou,Wenshen Wu,Feng Xing
A series of experiments were conducted to investigate the effect of seawater on the properties of alkali-activated slag (AAS) binders to seek further potentiality of these binders in marine environments. The experimental results show that on the one hand, seawater may lead to increased setting time, reduced compressive strength after 3 days and a less compact microstructure. On the other hand, however, it could also slightly improve the early age strength, flexural bending strength (after 28 and 56 days) and fractural toughness, and shows almost no impact on the fluidity of AAS binders. Moreover, with the formation of some new hydration products due to seawater mixing, the water absorption and volume of permeable voids had small decreases while the capillary sorptivity obtained a small increase. The concomitant of the acceleration effect due to the presence of salts and hindrance caused by the interaction between the seawater-based alkaline activator and slag make the AAS binding system more complex compared to the distilled water mixed counterparts. The findings of this study reveal the possibility of seawater used as the mixing water for AAS binders in marine or coastal areas.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Yun Li,Haotian Xue,Pekka Taskinen,Shenghai Yang,Chaobo Tang,Wei Jin,Yongming Chen,Ari Jokilaakso
This work proposes a novel environmentally-friendly, low temperature phase-conversion method for antimony extraction and studies its experimental application and feasibility in pyrite cinder waste co-treatment. The detailed phase transformations and microstructural evolution mechanisms during antimony extraction and sulfur fixation process were investigated. The results show that stibnite (Sb 2 S 3 ) can quickly transform to senarmontite (Sb 2 O 3 ) in the presence of Fe 2 O 3 and Na 2 CO 3 , and then Sb 2 O 3 will be continuously reduced into metallic Sb. Sulfur in Sb 2 S 3 was conserved as FeS and Na 2 S x O y (Na 2 S, Na 2 SO 4 and/or Na 2 S 2 O 3 ). As a result, sulfur was immobilized and recycled in the solid state resource, instead of emitting SO 2 gas. Laboratory-scale batch experiments employed pyrite cinder as sulfur-fixing agent indicate that more than 92.6% of antimony can be extracted and recovered by one step conversion from stibnite at 1123 K (850 °C) by this new technique. 97.3% of sulfur was fixed and converted to sulfide as matte and sulfate. In other words, SO 2 emissions were reduced by 97.3%. By-product elemental sulfur was produced after the water-leaching step, and finally producing industrial H 2 SO 4 . Iron contained in pyrite cinder waste will also be recycled. This novel method is an energy-saving, environmentally friendly and promising alternative for antimony extraction and waste treatment .
研究领域:
冶金学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Water
·
2021
·Vol. 13
·期 19
·2735
·
IF 3.103
Yali Wang,Huining Li,Suping Cui,Qi Wei
The potential possibility of blast furnace slag as a low-cost adsorbent to remove lead ions from wastewater was investigated in detail in the present work. Both single factor experiment and orthogonal experiment were performed to reveal the effect of pH, adsorption temperature, contact time and initial concentration of lead ions on the adsorption performance of pristine slag. In order to make clear the correlation between the lead ion adsorption performance and the structure of slag, solid state nuclear magnetic resonance (NMR) was conducted to reveal the network structure and X-ray fluorescence (XRF) was used to calculate the nonbridging oxygen in the network-forming tetrahedra. For the purpose of improving the adsorption performance, γ-aminopropyltriethoxysilane (APTES) was adopted to modify the slag via post-grafting method. The results show that the slag is predominately composed of SiO2, Al2O3, CaO and MgO, exhibiting an amorphous network structure based on SiO4and AlO4tetrahedra. The conditions for adsorption can be optimized as follows: a pH of 7, an adsorption temperature of 60 °C, a contact time of 120 min and an initial lead ion concentration of 40 mg·L−1. Under the optimal conditions, a removal rate of 99.98% and an adsorption capacity of 49.99 mg·g−1are obtained for the pristine slag. The adsorption complies with the Langmuir model thermodynamically and conforms to the pseudo-second order model kinetically. It is noted that aminopropyl-modification has considerably enhanced the removal rate of lead ions from 20.71 to 64.32% and the adsorption capacity from 29.01 to 96.48 mg·g−1since amino groups (-NH2) are more inclined to form a complex with lead ions than hydroxyl groups due to the higher nucleophilicity of amino groups than that of hydroxyl groups. However, it is necessary to develop more low-cost modification agents in the future work.Keywords:blast furnace slag;lead ions;adsorption;surface modification;aminopropyl groups
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）