Heavy-metal contamination poses a significant global threat to soil environments, underscoring the necessity for effective and sustainable remediation technologies. This review methodically summarizes advances in the field of microbial remediation of heavy metal-contaminated soils, organized around four major dimensions: remediation mechanisms, synergistic technologies, field applications, and future prospects. Firstly, the remediation mechanisms are elucidated, encompassing molecular interactions, cellular adaptation, and community-level cooperative responses. Secondly, the integration of microbes with functional materials and bioelectrochemical systems (BESs) is evaluated, with these materials providing support, electron mediation, and micro-environment regulation that markedly improve remediation efficiency and stability. Moreover, illustrative field cases demonstrate pivotal technological pathways and cost-effectiveness when transitioning from laboratory- to field-scale applications. Finally, emerging frontiers such as synthetic biology-engineered microbes, AI-driven microbial design, circular-economy value recovery, and policy-governance innovations are discussed, proposing essential elements for building a “predictable-controllable-sustainable” microbial remediation platform. This review aims to provide a comprehensive knowledge framework for researchers and to offer decision-making guidance for practitioners and policymakers, thereby advancing microbial remediation toward higher efficiency, reliability, and scalability.

The production process of antimony produces a large amount of solid waste, such as waste rock in mining, tailings in the beneficiation, metallurgical slag in the smelting, and so on. At present, most of these solid wastes are currently in storage, and the storage of a large amount of solid wastes is not only harmful to the local ecological environment but also a waste of resources. In view of this situation, this paper will take antimony tailings and metallurgical slag as examples and summarize them according to their different treatment methods. The comprehensive utilization of antimony tailings is mainly recovering metals by beneficiation and metallurgy and using antimony tailings as building materials and underground filling materials, while the comprehensive utilization method of antimony metallurgical slag is mainly the recovery of valuable metals by pyrometallurgy or hydrometallurgy or the stabilization technology. This paper summarizes the advantages and disadvantages of different treatment methods and puts forward the prospect of future research directions for the treatment of different metallurgical slags and tailings.

In response to the pressing environmental challenges posed by electrolytic manganese residue (EMR) and red mud (RM), this study proposes an innovative cementitious material technology for the synergistic co-utilization of these industrial wastes. By employing steel slag (SS) as a calcium-rich skeleton, the system effectively immobilizes sulfates from EMR and alkalinity from RM, converting hazardous wastes into value-added construction materials. Through orthogonal experimentation, an optimal mix proportion was established—30% RM, 20% EMR, and 50% SS at a water-to-binder ratio of 0.28—which achieved a 28-day compressive strength of 20.40 MPa, meeting relevant industry standards for auxiliary cementitious materials. Microstructural analysis unveiled a multi-stage alkali-sulfate synergistic activation mechanism: (1) the high alkalinity derived from RM rapidly activates the dissolution of aluminosilicate phases in both SS and EMR; (2) sulfate ions released from EMR promote extensive formation of ettringite (AFt), enhancing early-age structural integrity; and (3) calcium ions from SS facilitate the development of a dense C-S-H gel matrix, which serves as the primary binding phase. More profoundly, this process exemplifies a self-stabilizing waste-to-resource conversion mechanism, whereby harmful constituents (sulfates and free alkalis) are constructively incorporated into stable hydration products. This work not only elucidates a coherent scientific framework for the safe and efficient reclamation of multi-source solid wastes, but also demonstrates a scalable and ecologically viable pathway for million-ton-scale valorization of EMR and RM. Furthermore, it presents feasibility insights for the application of high-dosage steel slag-based material systems, thereby unifying significant environmental and economic advantages.

Exploring efficient methods to enhance leaching efficiency is critical for bioleaching technology to deal with sulfide concentrate. In our study, a novel artificial microbial community was established to augment the bioleaching efficiency and recovery of copper (Cu) and zinc (Zn). The optimum parameters in bioleaching experiments were explored according to compare a series of conditions from gradient experiments: the pH value was 1.2, temperature was 45 °C, and rotation speed was 160 r/min, which were different with pure microorganism growth conditions. Under optimal conditions, the result of recovery for Cu and Zn indicated that the average leaching rate reached to 80% and 100% respectively, which almost increased 1.8 times and 1.2 times more than control (aseptic condition) group. Therefore, this method of Cu and Zn recovery using a new-type artificial microbial community is expected to be an environmentally-friendly and efficient bioleaching technology solution, which has the potential of large-field engineering application in the future.

Natural silicate minerals have a wide range of applications as green, non-toxic and low-cost materials. In this paper, hydrophilic anti-fog films of silicate minerals were generated via a vacuum evaporation coating method using natural feldspar minerals as raw material. Thermogravimetric analysis shows that the feldspar changes its structure during the coating process, which in turn changes the roughness of the film and improves the hydrophilicity of the film. The hydrophilicity, anti-fogging properties, optical properties and surface morphology of the films were characterized by contact angle measurements, the hydrothermal method, UV-VIS spectrophotometer and atomic force microscopy, respectively. The results show that the mineral films have excellent hydrophilicity. The best anti-fog effect was achieved at a minimum contact angle of 22.3° with water when the thickness of the film was 100 nm. The anti-fog effect gradually decreased with the increasing thickness of the film. The optical transmittance test showed that the film material had a negligible effect on the transmittance of the substrate. When the film thickness was 100 nm, the maximum optical transmittance was 92.2%. This is 4.5% higher than when the film was uncoated, which has a specific visual transmittance effect.

Fly ash is a kind of industrial solid waste that is considered “hazardous waste”. In this study, a supporting matrix of modified fly ash (MFA) was employed to package lauric acid (LA) via a facile direct impregnation method involving less experimental error. A low-cost and eco-friendly form-stable phase change material (PCM) of LA/MFA/graphene (G) was fabricated, with G as the thermal conductivity enhancer. The preparation and leakage testing of an LA/MFA/G form-stable PCM (FSPCM) were investigated in detail. The leakage test results indicated that good package efficiency was obtained using MFA with a higher specific surface area and richer pore structure to pack the LA. Then, LA/MFA/G composites were characterized via scanning electronic microscope (SEM), Fourier transform infrared spectroscope (FTIR), differential scanning calorimeter (DSC), and thermal gravimetric analyzer (TGA). The results showed that excellent form stability was obtained by adding MFA as the supporting matrix. The SEM analysis indicated that LA could be well dispersed into the structure of MFA. The FTIR analysis demonstrated that the components of the FSPCM were quite compatible. The results of the DSC illustrated that LA/MFA/G (5 wt. %) had a melting point of 45.38 °C and a latent heat of 41.08 J/g. The TGA analysis revealed that the prepared FSPCM had better thermal stability compared with LA within its working temperature range. In addition, the effects of G on the heat transfer performance of the prepared FSPCM were examined. In short, using MFA with a higher specific surface area and richer pore structure to pack the LA via a simple preparation process with less experimental error can contribute to good performance. The research not only improved the comprehensive utilization of solid waste, but also promotes the application of FSPCM in the field of building energy conservation.