Red Mud Research Articles

Durability evaluation of a high-performance red mud-based composite material

The industrial solid waste red mud (RM) was served as a raw material, supplemented with high activity of high-calcium fly ash (HCFA) and low-calcium fly ash (LCFA), a red mud-based composite material (RBC) was obtained. Through the activation of a mixed solution (MS) of NaOH and water glass and the optimization of the preparation process, the prepared RBC possessed a high-performance with high strength and environmental protection. The chemical corrosion and freeze-thaw properties of the RBC were investigated by full immersion and rapid freeze-thaw methods. The strength and durability mechanisms of the RBC were explored by micro-testing techniques. The results indicated that adjusting the operated temperature of the alkaline activator can ensure paste compatibility and shorten the initial setting time. According to the integrity, economy and mechanics properties of the RBC, it is comprehensively determined that the method of wrapped steam-cured, the optimum curing time of RM-HCFA-MS and RM-LCFA-MS was 14 d and 21 d, respectively, and the corresponding compressive strength was 52.8 MPa and 58.9 MPa, respectively. When immersed in acidic, alkaline, or saline environments, the RBC consistently maintained its original structural morphology exhibiting strong corrosion resistance performance. Additionally, the maximum compressive strength was decreased by 19.5%, the maximum mass loss rate was 1.74%, and the corrosion resistance coefficients exceeded 75% after corrosion. The RBC was freeze-swelled and ruptured under repeated actions of hydrostatic and infiltration pressures, and the frost resistance ratings of RM-HCFA-MS and RM-LCFA-MS were F105 and F120, respectively. In conclusion, the RBC has good corrosion resistance and frost-thaw resistance.

The role of different ratios of biochar in the artificial lightweight cold-bonded aggregates (ALCBAs) containing high volume of red mud (RM)

To explore new channels for the effective recycling of red mud (RM) in the field of construction-related materials, and study the feasibility of applying biochar (BC) and RM into capturing CO2, this study developed the artificial lightweight cold-bonded aggregates mixed with high volume of RM (RM-ALCBAs). Different amount of BC (0%, 5%, 10% and 15%) was also added to the RM-ALCBAs, and a set of quantitative devices for assessing carbon absorption of RM-ALCBAs was innovatively developed. Meanwhile, its compressive strength, water absorption rate and apparent density were tested, and then the microscopic properties of RM-ALCBAs were also investigated by using TGA, XRD, SEM-EDS, MIP. Finally, the sustainability and heavy metal leaning behavior of RM-ALCBAs were assessed. It was found that the total carbon uptake of RM-ALCBAs was about 30.58–33.06 kg/tons, indicating that RM-ALCBAs show the obvious carbon-capturing potential, and when the biochar dosage was increased from 0% to 15%, its compressive strength was 1.28 MPa-1.98 MPa, and the water absorption rate and apparent density of RM-ALCBAs before carbonation were 17.96%-20.46% and 1.85 g/cm3-1.98 g/cm3, while the water absorption rate and apparent density of RM-ALCBAs after carbonation were 16.71%-17.04% and 2.02 g/cm3-1.83 g/cm3, respectively, which is in accordance with the specification of LWAs in China. With the increase of BC doping, the porosity in RM-ALCBAs gradually increased, the proportion of micropores gradually decreased, and the proportion of macropores gradually increased. More importantly, converting RM into RM-ALCBAs can effectively lower the toxic leaching and the concentration of heavy metals is also meet the Chinese requirements. RM-ALCBAs mixed with 5% BC has the lowest energy consumption per-unit compressive strength, carbon emission per-unit compressive strength with about 26.0–29.1 kg/t, and cost per-unit compressive strength with much lower than that of FA-ALCBAs and GGBFS-ALCBAs. Overall, the RM-ALCBAs have obvious eco-friendly potentials and belong to the carbon-negative construction materials that can effectively recycle solid waste of RM, which can provide some new insights and useful data for the development path of low-carbon ALCBAs.

Synthesis characterization and sorption properties of nanoscale zero valent iron using red mud as the iron source: cadmium removal from spiked aqueous solutions

<p>The aim of the present study was to synthesize a sorbent material, nanoscale zero valent iron (n ZVI), using red mud as the iron source in the framework of circular economy. The sorbent synthesized was tested for Cd removal from spiked aqueous solutions. For the synthesis of the sorbent, iron reductive precipitation was used. The specific surface area (BET method) of the sorbent prepared was determined, while its surface composition, morphology, and texture were examined by powder X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM-EDX). The sorption efficiency of the sorbent produced was inve-1stigated with kinetic and equilibrium experiments, performed in batch conditions. MATLAB software was used to fit experimental data to Langmuir and Freundlich equations. The results of the study showed that with the described process, nanoscale zero valent iron was prepared with grain size 81 and 89 nm and specific surface area of 36.59 and 28.9 m2·g-1 depended on the synthesis procedure followed. The sorbent appeared to be efficient for Cd removal from spiked aqueous solutions. Kinetic experiments proved that equilibrium was achieved within 24h while the maximum sorption capacity as evidenced by equilibrium experiments was 65 mg·g-1. Data proved to follow the pseudo second order model and to fit better to the Langmuir equation.</p>

Red mud supported Ni-Cu bimetallic material for hydrothermal production of hydrogen from biomass

Exploring efficient and reliable catalysts to achieve gasification of biomass waste is a promising research endeavour. In this study solid waste red mud (RM, an inexpensive and efficient support) loaded Ni-Cu metals (Ni-Cu/RM) was used to catalyze hydrothermal gasification of cotton stalk at 340–400 ℃ and 16–30 MPa. In the presence of Ni-Cu/RM catalyst, 21.88 mmol/g H2 yield with 79.89% carbon balance was achieved, increased by 22.8 times under the optimized conditions (380 ℃ for 5 min) based on orthogonal experiments. Under the optimal conditions, H2 yield with neat Ni and Ni/RM loaded on RM is 0.96 and 12.94 mmol/g, respectively due to the specific surface area soaring by 72.0 times from 0.7 to 50.5 m2/g. With Ni-Cu/RM bimetallic catalyst, H2 yield jumped from 3.41 to 21.88 mmol/g, 6.7 times higher than that neat Ni, or reached 84% with Ni-Cu/Al2O3 if Al2O3 was as support. It is further found that Cu promoted the dispersion of Ni on red mud with surface area rising from 50.47 to 73.42 m2/g together with forming Ni-Cu alloy (alkalinity of Ni-Cu/RM rose to 285.65 from 172.21 μmol/g for Ni/RM) enhanced H2 generation. When temperature grew from 340 ℃ to 400 ℃ (supercritical), H2 yield improved by 3 times from 9.21 to 28.50 mmol/g. Red mud is an ideal candidate for replacing the commercial support Al2O3.

Lanthanum-Modified Phosphogypsum Red Mud Composite for the Co-Adsorption of Cadmium and Arsenic: Mechanism Study and Soil Remediation

Lanthanum-Modified Phosphogypsum Red Mud Composite for the Co-Adsorption of Cadmium and Arsenic: Mechanism Study and Soil Remediation

In-situ preparation of porous metal-ceramic composite from secondary aluminum dross and red mud for adsorption of organic pollutant

Secondary aluminum dross (SAD) and red mud (RM) are solid waste discharged from aluminum industry. SAD contains 10–25 wt% aluminum nitride (AlN) and RM contains 20–50 wt% iron oxide. In this work, porous metal-ceramic composite was in-situ made from SAD and RM. Iron oxide was reduced into Fe2Si by AlN, and the generated nitrogen created pores. It was studied that effect of raw material and thermal treatment on pore structure and properties of the composite. Porosity, bulk density and compressive strength of composite were 65.78%, 1.03 g/cm3 and 17.77 MPa, when SAD content was 40 wt% and sintering temperature was 1450 °C. About 95.9% of malachite green in waste water was adsorbed by composite after 24 h. The composite could be recycled by magnetic separation after adsorption, attributed to the magnetic Fe2Si. This work proposed a novel idea of making recyclable porous material for adsorption of organics in waste water.

Waste-derived catalysts for tar cracking in hot syngas cleaning

Catalytic tar cracking is a promising technique for hot syngas cleaning unit in gasification plants because it can preserve tars chemical energy, so increasing the syngas heating value. The cost associated with catalyst preparation is a key issue, together with its deactivation induced by coke deposition. Iron is a cheap and frequently used catalyst, which can also be found in some industrial wastes. The study aims to assess the catalytic efficiency for tar cracking of two waste-derived materials (red mud and sewage sludge) having high content of iron. The catalysts were supported on spheres of γ-Al2O3, and their efficiency was compared to that of a pure iron catalyst. The role of support was investigated by testing pure red mud, with and without the support. A series of long-term tests using naphthalene as tar model compound were carried out under different values of process temperatures (750 °C-800 °C) and steam concentrations (0 %-7.5 %). The waste derived catalysts showed lower hydrogen yields compared to pure iron catalyst, due to their lower content of iron. On the other hand, the conversion efficiencies of all the tested catalysts resulted rather similar, since the Alkali and Alkaline-Earth Metallic species present on the surface of waste-derived catalyst help in preventing coke deposition. The iron oxidation state appears to play an important role, with reduced iron more active than its oxidised form in the tar cracking reactions. This indicates the importance of tuning steam concentration to keep constant the reduced state of iron while limiting coke deposition.

Recovery of Iron and Alumina from Iron-Rich Bauxite, Red Mud, and Fly Ash by Reduction Smelting with Steel Slag

Recovery of Iron and Alumina from Iron-Rich Bauxite, Red Mud, and Fly Ash by Reduction Smelting with Steel Slag

Ultrasonic-enhanced phosphorus sludge excited O3 coupled red mud simultaneous desulfurization and denitrification

The SO2/NOX pollution in the flue gas of non-ferrous smelting is increasingly serious. At the same time, the accumulation of red mud (RM) in the aluminum industry and phosphorus sludge (PS) in the yellow phosphorus industry has caused serious harm to the environment. To remove SO2 and NOX from the non-ferrous smelting flue gas and realize the resource utilization of the above two solid wastes, an ultrasonic field was used in this study to strengthen the PS excited O3 process and RM wet desulfurization and denitrification process. In the process of O3 excitation, the response surface method (RSM) is used to obtain the optimal O3 excitation concentration, and the optimal reaction conditions are designed based on the response surface optimization model: T is 53.226 °C, power density is 0.4 W/cm2, PS concentration is 51.433 g/L, O3 formation concentration up to 250 ppm or more, which provides a theoretical basis for subsequent desulfurization and denitrification steps. It is proved that this study can replace the expensive traditional O3 generator and provide a basis for NOX removal in the following process. In addition, the optimum experimental conditions of ultrasonic enhanced RM desulfurization and denitrification process were also explored. Under ultrasonic frequency of 28 kHz, ultrasonic power density of 0.4 W/cm2, T of 50 °C, RM concentration of 15 g/L, and stirring intensity of 1000 rpm, the desulfurization efficiency of the reaction system can be maintained above 95 % within 250 min, and the denitrification efficiency can be maintained above 90 % within 250 min. The effect of desulfurization and denitrification in this study is much better than that of traditional methods. Finally, the reaction mechanism of ultrasonic enhanced O3 excitation and RM wet desulfurization and nitrogen removal was discussed by combining adsorption thermodynamics, isotherm, and kinetics. The results showed that the OH· free radicals generated by ultrasonic cavitation and the physical effects brought by emulsification had significant promoting effects.

Chromium immobilization from wastewater via iron-modified hydrochar: Different iron fabricants and practicality assessment

The recycling of industrial solid by-products such as red mud (RM) has become an urgent priority, due to their large quantities and lack of reutilization methods can lead to resource wastage. In this work, RM was employed to fabricate green hydrochar (HC) to prepare zero-valent iron (ZVI) modified carbonous materials, and conventional iron salts (IS, FeCl3) was applied as comparison, fabricated HC labeled as RM/HC and IS/HC, respectively. The physicochemical properties of these HC were comprehensively characterized. Further, hexavalent chromium (Cr(VI)) removal performance was assessed (375.66 and 337.19 mg/g for RM/HC and IS/HC, respectively). The influence of dosage and initial pH were evaluated, while isotherms, kinetics, and thermodynamics analysis were also conducted, to mimic the surface interactions. The stability and recyclability of adsorbents also verified, while the practical feasibility was assessed by bok choy-planting experiment. This work revealed that RM can be used as a high value and green fabricant for HC the effective removal of chromium contaminants from the wastewater.

Sonodegradation of Sulfamethoxazole in Water Using Red Mud and Rice Husk Biochar Catalysis

This research evaluated the effectiveness of sulfamethoxazole (SMX) antibiotic degradation in aqueous solution using red mud and rice husk biochar (RMC) as catalytic material for ultrasound-supported degradation process. Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), and Energy-dispersive X-ray spectroscopy (EDX) were applied to study the characteristics of the catalytic material. The results demonstrated that the main components of RMC catalytic material are C, O, Si, and Fe elements with high weight percentage of 26.56%, 50.89%, 1.86% and 10.26%, respectively, and with high crystallized mix ratio. These are beneficial for SMX degradation reactions in water under the effect of ultrasound irradiation. The SMX degradation products were analyzed using High-performance liquid chromatography (HPLC). The effect of pH, contact time, initial concentration, and catalyst weight on degradation effectiveness were also investigated. The highest degradation efficiency of 75% at the treated rate of 15 mg SMX/g RMC was observed at pH = 3, contact time of 180 minutes, initial concentration of 20 mg SMX/L. This suggested a new solution to utilize the waste resources for waste treatment.
  

Experimental Study and Effectiveness Evaluation on the Rapid Antiquing of Red Sandstone in Ancient Buildings Restoration

As there are few cases of red sandstone rapid antiquing in ancient buildings and as it is difficult to reproduce, this paper carried out an experimental study and effect evaluation assessment on red sandstone rapid antiquing in the restoration of ancient buildings, based on a restoration project of an ancient town in Ganzhou. The method and the implementation process of red sandstone rapid antiquing are proposed by starting from color antiquing and texture antiquing. By controlling the concentration of red mud, grass ash, and carbon black in color coatings as variables, using the HSV (hue, saturation, value) color space and Tamura texture features (roughness, contrast, orientation) to quantitatively analyze the antiquing effect, an analytical model for evaluating the red sandstone antiquing effect based on image processing was established. The results showed that among all the antiquing groups, the group that used white cement, green zeolite, imitation greenery, red clay, grass ash, and 5 mL/L carbon black liquid at the same time had the best effect, with a qualified rate of 90%. The analytical model can improve the evaluation efficiency of red sandstone antiquing and avoid errors caused by subjective factors. With feasibility and practicability, the model is conducive for new red sandstone to meet the requirements of ancient building restoration through rapid antiquing. It provides a scientific basis and technical reference for red sandstone antiquing in stone cultural relics and ancient building restoration.

A simple but effective method for the enrichment of Al in red mud waste

This study proposes transforming red mud, an abundant byproduct from the aluminum industry, into minerals using Na2CO3 activation for efficient water leaching. It was aimed at breaking down the rigid Al-Si network structure. The investigation compares the effects of sodium salts, with Na2CO3 achieving an 88.90 % aluminum leaching rate crucial for activating katoite and cancrinite in red mud. Using XRD, FT-IR, SEM-EDS, in situ hot-stage microscopy, FactSage, and Material Flow Analysis, the study explores changes in Na2CO3-loaded red mud, elucidating its role in converting aluminum-bearing minerals into water-soluble aluminates at a low temperature of 900 °C for an optimum activation duration of 90 min, with a preferred loading of 32 % Na2CO3. Introducing a new cyclic aluminum extraction method from red mud, utilizing sodium salts, especially Na2CO3, the study optimizes the activation process through a comprehensive exploration of thermal and mineral transformation behaviors. Quantitative analysis of Na and Al elements ensures successful recovery and cyclic utilization of Na2CO3, maintaining aluminum extraction efficiency above 82 % after six cycles. This economically feasible closed-loop system aligns with principles of industrial efficiency and climate change mitigation. Na2CO3, acting as an activator and a carbon sink, showcases significant potential for sustainable aluminum production.

Properties of Fluorine-Free Steelmaking Flux Prepared Using Red Mud

The basic oxygen steelmaking process is based on the CaO-FeO-SiO2 ternary slag system, characterized by a high melting point and low lime dissolution rate, often becoming one of the key factors limiting the efficiency of the converter. The bulk solid waste red mud, produced by the Bayer alumina process and rich in Fe2O3/Al2O3/Na2O, significantly reduces the melting point of the steelmaking slag system and enhances the efficiency of lime dissolution. This study utilized red mud as the main raw material to prepare a fluoride-free flux. An in situ online observation system was used to measure the melting point of the flux and the dissolution rate of lime in the flux. The results indicate that the melting point of the red mud-based flux is below 1200 °C, and under the same conditions, the lime dissolution rate is 10 to 15 times higher than when this flux is not used. Experiments in a 10 kg induction furnace show that using this flux, the dephosphorization rate under conditions without oxygen blowing is close to 40%, far higher than the rate achieved using CaF2. Under oxygen-blowing conditions, the dephosphorization rate using the red mud-based flux is comparable to that of CaF2, and significantly higher than without any flux, especially under high [C] content conditions. The data show that the red mud-based flux has the potential to be widely used as a fluoride-free flux in the steelmaking process.

In-Depth Insight into the Effects of Steel Slag and Calcium Hydroxide on the Properties of a Fly Ash-Red Mud Geopolymer.

The low mechanical strength of a low-calcium fly ash (FA)-red mud (RM) geopolymer severely limits its application. Steel slag (SS) and Ca(OH)2 can provide calcium and alkali for the hydration process of a low-calcium FA-based geopolymer. In this study, SS was used to replace part of the RM, and Ca(OH)2 was introduced. The effects of SS and Ca(OH)2 on the properties of the FA-RM geopolymer were investigated. The experimental results show that SS promoted the matrix to generate more C(N)-A-S-H and C-S-H gels and optimized the pore structure, thereby improving the mechanical properties of the FA-based geopolymer. The addition of 4 wt.% Ca(OH)2 increased the hydration products of the FA-based geopolymer, the microstructure was denser, and the mechanical properties were significantly improved. The 28 d compressive strength of the FA-based ternary composite geopolymer prepared by replacing part of the RM with SS and adding Ca(OH)2 reached 30.6 MPa, which provided an experimental basis for the resource utilization of various bulk solid wastes.

A Novel Method of Synthesizing Polymeric Aluminum Ferric Sulfate Flocculant and Preparing Red Mud-Based Ceramsite.

A synthetic flocculant of aluminum (Al) and iron (Fe) extracted from red mud (RM) has been widely used in sewage treatment, while the remaining RM residue has been ignored. This study aimed to synthesize polymeric aluminum ferric sulfate (PAFS) flocculant from RM by acid leaching and then use the acidified RM residue to produce an acid RM-based ceramsite (ARMC) by mixing bentonite, hydroxypropyl methylcellulose, and starch. Our results showed that sintering, reaction temperature, H2SO4 concentration, reaction time, and liquid-to-solid ratio had an obvious effect on the leaching of Al and Fe in RM, which was a necessary prerequisite for the efficient PAFS flocculants. At a PAFS dosage of 60 mg/L, turbidity and phosphate removal rates were 95.21 ± 0.64% and 89.17 ± 0.52%, respectively. When the pH value was 8.0, the turbidity and phosphate removal efficiency were 99.22 ± 0.66% and 95.98 ± 1.63%, respectively. Considering the adsorption capacity and mechanical properties, the best conditions for ARMC production included using 60% ARM and ceramsite calcination at 600 °C, with the BET surface area 56.16 m2/g and a pore volume of 0.167 cm3/g. Thermogravimetric analysis indicated that 400 °C was a reasonable preheating temperature to enhance the ARMC mechanical strength, as this temperature allows the removal of surface-adsorbed and constituent water. Under a scanning electron microscope, the ARMC appeared rough before adsorption, while relatively uniform pores occupied it after adsorption. Our conclusion will help to improve the zero-waste strategy of RM and speed up the industrial production of RM in flocculants as well as utilizing ARMC as a new type of adsorbent for phosphorus adsorption in sewage treatment.

Silica Fume-Red Mud Based Geopolymer Stabilized Organic Soil

Organic soil presents significant challenges for construction due to its unsuitability as a soil type, often necessitating stabilization using conventional agents like cement. The Silica Fume (SF)-Red Mud (RM) binder mix emerges as a promising alternative stabilizer due to its low carbon footprint coupled with its superior strength-enhancing properties. In this study,we explore the feasibility of employing SF-RM based geopolymer to stabilize organic soil. To activate the collected samples, a solution of sodium hydroxide (NaOH) with molarity (M) of 6, 9, and 12 were utilized, as well as binder (SF + RM) proportions of 10%, 20%, 30%, and 40% relative to dried organic soil and alkali-to-binder (A/B) proportions of 0.5, 0.7, and 0.9, respectively. The experimental results reveal that a variety of factors, including NaOH molarity, A/B proportions, pH, and curing duration, have an effect on the unconfined compressive strength (UCS) of treated organic soil. The best combination was obtained with a binder concentration of 30%, a NaOH molarity of 9M, and an A/B proportion of 0.7. After 28 days of curing, the UCS of the treated organic soil (1714 kPa) was found to be 168 times that of the untreated organic soil (10.2kPa). Further, the production of compounds such as aluminium silicate, sodium aluminosilicate, and potassium aluminosilicate, which have been found by X-ray diffraction (XRD) research, can be ascribed to the increase in strength. Furthermore, when subjected to analysis through Field Emission Scanning Electron Microscopy (FESEM), it becomes evident that these items play a pivotal role in filling the voids within the soil-binder composite. As a consequence, they facilitate the creation of a more smoother, compact and denser structure.

Enhancing kitchen waste anaerobic digestion by recycled aluminum industry waste: Alkali treatment and potential electron transfer mechanism

Kitchen waste has become a significant environmental concern worldwide. Red mud, an industrial solid waste characterized by its porous structure and high iron oxide content, exhibits potential as a conductive conduit in the direct interspecies electron transfer (DIET) pathway. In this study, red mud pretreatment of kitchen waste was conducted to enhance anaerobic digestion (AD). The effect and mechanism of enhancing kitchen waste AD by red mud pretreatment was studied for the first time. Results indicated that red mud pretreatment could accelerate the hydrolysis of organic compounds and alleviate the acid inhibition. Consequently, the methane production rate was increased from 260.7 mL/g VS to 402.3 mL/g VS, i.e., up to 54.3%. And volatile solids removal efficiency was increased from 53.9% to 73.1%, i.e., up to 35.6%. Furthermore, microbial community analysis revealed the enrichment of electrochemically active bacteria (Synergistaceae), acetogenic bacteria (Syntrophomonadaceae) and methanogens (Methanobacterium and Methanosarcina), which played essential roles in interspecies hydrogen transfer (IHT) and DIET. This study showed that red mud pretreatment has the potential to enhance kitchen waste AD which contributes to carbon mitigation. It also threw the potential new insights to the relative mechanism.

Efficient removal of 17α-ethinylestradiol by algae-based red mud catalyst activated persulfate: Removal mechanism and defect of quenching

The synthesis and optimization of carbon-based materials, derived from various solid waste sources to activate peroxydisulfate (PDS), offer a practical approach that addresses both the recycling of solid waste resources and the removal of recalcitrant organic pollutants. In this study, stacked algae sludge and discarded red mud solid waste were repurposed to synthesize an algae-based red mud catalyst (AR-BC) using the carbon-thermal reduction technique. The obtained AR-BC catalyst exhibited efficient adsorption and degradation capabilities for 17α-ethinylestradiol (EE2). The results showed that AR-BC can adsorb 42.67 % of EE2 at equilibrium, with a maximum capacity of 8.0 mg/g. After the activation of PDS by the AR-BC catalyst, it was observed that EE2 was completely degraded within 20 min. The superior activation ability is mainly attributed to the presence of Fe3O4 and oxygen-containing functional groups in AR-BC. Both free radicals and non-free radicals coexisted in the AR-BC/PDS system, with the former predominantly influencing the EE2 degradation process. And hydroxyl radical was identified as the primary reactive oxygen species. Moreover, AR-BC exhibited robust adaptability and reusability in real water for efficient adsorption and degradation of EE2. This study presents a viable solution by seamlessly integrating resource recycling with pollutant removal, offering an innovation approach.

Upcycling use of red mud-based solid waste in engineered cementitious composites: Properties, activation mechanism, and life-cycle assessment

In this study, a low-carbon engineered cementitious composite (ECC) was produced by combining alkali-activated red mud (RM)/ground granulated blast-furnace slag (GGBS) with polyvinyl alcohol (PVA) fibers as the reinforcement. Both calcium aluminosilicate hydrate (C-A-S-H) and sodium aluminosilicate hydrate (N-A-S-H) gels are detected in the reaction products. A higher modulus of sodium silicate in the activator results in a higher degree of reaction of silicates in the samples, but not promising a higher mechanical property. The potential mechanism of iron activation in the alkali-activation RM-based ECC system was revealed. The four-point bending test results indicate a large deflection ability and multiple cracking characteristics of the composite. Life cycle assessment of this system is also presented by calculating energy consumption and carbon emissions. This study not only sheds light on the feasibility of using RM in the preparation of high-toughness alkali-activated ECC but also provides a promising method to upcycle industrial solid wastes in a highly effective way.