Waste tire pyrolytic carbon black (CBp) is characterized by high ash content, while conventional demineralization processes often suffer from incomplete impurity removal or fluorinated wastewater generation, limiting its large-scale reutilization. To address these challenges, a fluorine-free deep demineralization strategy coupling stepwise acid–alkali treatment with controlled mechanical activation was developed. The process enabled efficient purification while preserving the carbon framework, with a 46% increase in specific surface area. Compared with acid–alkali treatment alone, moderate ball milling promoted particle deagglomeration, enhanced mineral exposure, and improved mass transfer, thereby facilitating siliceous impurity removal. However, excessive milling led to secondary agglomeration and structural densification, which negatively affected demineralization efficiency, as evidenced by an increase in residual ash to 1.98% at 80 min. Under optimized conditions (300 rpm, 40 min, ball-to-powder ratio of 10:1), the ash content was reduced from 17.93% to 0.69%, outperforming acid–alkali treatment alone (1.40%). The proposed fluorine-free process satisfied the industrial requirement for rubber-grade carbon black while offering improved environmental compatibility, providing a sustainable route for CBp valorization.

To address the issues of high acid consumption, hydrogen sulfide release, and poor solubility associated with conventional acid leaching of iron-bearing ores containing Fe, Fe3C, and FeS, this study proposes a combined process involving hydrogen peroxide-directed pre-oxidation and electric field-enhanced acid leaching. Theoretical analysis was conducted using thermodynamic calculations, Eh-pH diagrams, and first-principles simulations. Additionally, XRD, BET, and EDS characterization was employed to investigate the physicochemical properties of the leaching process and the mechanism of electric field enhancement, and process parameters were optimized through single-factor experiments. The results indicate that pre-oxidation converts sulfides into oxides, thereby mitigating hydrogen sulfide generation; the electric field creates a high-oxidation-potential environment through anode polarization, alters the dissolution pathway, and promotes the selective conversion of sulfur and sulfides into sulfate ions, while simultaneously enhancing ion migration and driving dissociation. Under optimal conditions (20% sulfuric acid, 90°C, solid-liquid ratio of 160 g/L, current density of 70 mA/cm², and leaching for 2 h), the iron leaching rate reached 92.31%, acid consumption was reduced by 42.9% compared to conventional leaching, and precious metals such as platinum and rhenium were concentrated in the leaching residue. This process enables the efficient and clean leaching of complex iron-bearing materials, providing technical support for resource recycling.

The high-value utilization of waste tire pyrolysis carbon black (CBp) is hindered by its high ash content, especially high zinc, sulfur and silicon content. However, the existing removal method generates a large amount of waste acid and alkali and fails to directly recover zinc. Based on the high-efficiency and green characteristics of microwaves, without the need to add additional reagents, this study efficiently removed and recovered zinc and sulfur by using the spontaneous reaction of substances inside the raw materials as well as the dissociation and regeneration of minerals. Moreover, sodium hydroxide (NaOH) was used to remove silicon. In this process, 99.94 % of zinc and 89.82 % of sulfur can be removed and recovered, and silicon is removed simultaneously. The fixed carbon content of CBp increased from 80.22 % to 94.02 %. The mechanism of dezincification and desulfurization via microwave treatment was investigated. It was found that CBp exhibits excellent dielectric properties, with a dielectric constant as high as 36.3 F/M. In the microwave field, the heat generated by the conductive polarization of carbon powder serves as the primary heat source for zinc and sulfur removal. During the entire process, zinc is removed in the form of ZnS and ZnO, while sulfur is removed as ZnS. Compared to conventional heating, microwave heating can achieve superior sulfur-removal and Zinc-removal efficiency at lower temperatures. The process offers a scalable, acid-free route for UNSDG-12 compliant valorisation of CBp, which is conducive to the effective utilization of solid waste resources.

The widespread industrial adoption of metal-organic frameworks (MOFs) is hindered by limitations inherent to conventional syntheses, such as high energy demands, reliance on toxic solvents, and poor scalability. This comprehensive review establishes ultrasonic synthesis (US) as a green and efficient alternative, systematically analyzing the fundamental mechanisms by which ultrasonic cavitation governs MOFs nucleation and growth kinetics, enabling rapid reactions, reduced crystal dimensions, and tailored defect densities. Critical advances in structural control strategies are examined, particle size/morphology optimization through US parameters; defect engineering for active site/pore functionality enhancement; and crystal facet regulation synergized with surface engineering. Breakthrough applications of US-synthesized MOFs are highlighted across domains: enhanced catalysis (electro-, photo-, enzyme); superior molecular recognition (gas adsorption/separation, water purification); high-capacity electrodes (supercapacitors, batteries); and targeted drug delivery/biosensing. Prospects for industrial scale-up of US-synthesized MOFs are analyzed. Persistent challenges in acoustic field uniformity and defect-property predictability are noted. Future perspectives emphasize in situ characterization and AI-guided optimization to unlock MOFs potential. By linking fundamental insights with practical applications, this review guides the development of high-performance MOFs for industry. We underscore US synthesis as a transformative platform for MOFs industrialization, aligning with UN Sustainable Development Goals through sustainable, cost-effective manufacturing.

Cr-coated Zr alloys suffer from severe oxidative dissolution in high-temperature oxygenated water, which restricts their widespread application in various reactor systems. Herein, an additional Zr outer coating is proposed to overcome this limitation. Long-term hydrothermal tests (300 days, 360 degrees C, 18.6 MPa) reveal that the Zr/Cr bilayer coating provides excellent corrosion resistance in both hydrogenated (3 ppm dissolved hydrogen) and highly oxygenated (1 ppm dissolved oxygen) environments, significantly outperforming uncoated and Cr-coated Zr alloys. A dense ZrO2 layer and an underlying (Zr,Cr)Ox amorphous layer form at the Zr/Cr interface, acting as effective protective barriers. The stability of the dense ZrO2 layer is attributed to grain refinement, which suppresses the tetragonal-to-monoclinic phase transformation. Driven by disparities in oxygen affinity, the amorphous layer develops a multilayered segregation of Cr-rich and (Zr,O)-rich regions, which arrests the oxidation front.

In order to effectively alleviate the environmental pressure, in this paper, FeTi/C nanomaterials were prepared by microwave-catalysed pyrolysis of PVC pretreated with dechlorination using homemade FeTiOx catalysts and applied in the field of phenol degradation. The dechlorinated pre-treated PVC contains only 0.41 wt

Sulfide precipitation is the most widely applied technology for treating acidic arsenic-laden wastewater, yet its practical implementation is plagued by intractable challenges: low reactivity between As (V) and S2−, excessive consumption of sulfiding agents, and insufficient arsenic removal that results in high residual arsenic in the effluent. To address these limitations, this study proposes a novel ultraviolet-formic acid synergistic sulfidation process. Under UV irradiation, formic acid undergoes photolysis to generate highly reactive hydrogen radicals (H•) and carboxyl radicals (•COOH). H• selectively reduces inert As (V) to the more reactive As (III), significantly lowering the activation energy for subsequent sulfide precipitation. Meanwhile, •COOH scavenges dissolved oxidative species, effectively inhibiting As (III) re-oxidation and ensuring the sulfidation reaction proceeds directionally. Additionally, these radicals modulate electrostatic and hydrogen bonding interactions in nascent As2S3 clusters, mitigating explosive nucleation and irregular agglomeration, and forming denser, more uniform precipitates that boost mass transfer and arsenic capture efficiency. This efficient, cost-effective and safe technology is ideal for copper smelting's high‑arsenic acidic wastewater and applicable to other strong acidic industrial arsenic wastewater, providing robust support for the green transformation of non-ferrous metallurgy.

The widespread use of benzophenone (BP)-type ultraviolet absorbers has raised growing concerns on the potential risks to both ecosystems and human health. In this study, a novel ionic liquid functionalized polymer (PS-CH2-[BrMim][Cl]) was prepared by chemical grafting and its performance to selectively remove benzophenone-5 (BP-5) from water was studied. It was shown that PS-CH2-[BrMim][Cl] not only exhibited an ultrahigh adsorption capacity of 834.7 mg/g for BP-5 at 3200 ppm, but also effectively enriched 85.9% of trace BP-5 (2.5 ppb) from high-salinity water, with an enrichment factor as high as 859.0. The adsorbent demonstrated rapid adsorption kinetics and 10 min was enough to achieve equilibrium. Even the content of coexisting inorganic ions such as Na+, K+, Ca2+, Mg2+, Cl-and NO3-in water was 50,000 times higher than that of BP-5, the removal efficiency remained almost unaffected. Notably, PS-CH2-[BrMim][Cl] also demonstrated good adsorption performance for benzophenone-type ultraviolet absorbers with similar structure to BP-5 and exhibited excellent recycling durability. Mechanism study indicated that the multiple interactions of hydrogen bonding, electrostatic attraction and ion exchange significantly contributed to the ultra-high adsorption of BP-5. As such, this work provides a new perspective for the removal of benzophenone-type ultraviolet absorbers from real environmental samples.

Persulfate-based advanced oxidation processes (PS-AOPs) represent a green and sustainable approach for degrading environmental contaminants like bisphenol A (BPA). However, the practical application of conventional heterogeneous iron-based catalysts in PS-AOPs is often hindered by their low atom-utilization efficiency, complex active sites, and suboptimal catalytic performance. To address these limitations, this study reports the successful synthesis of a single-atom iron catalyst anchored on 3D N-doped porous carbon (SAC-Fe) for efficient activation of peroxydisulfate (PDS) to degrade BPA. The SAC-Fe catalyst demonstrated superior performance, achieving 100% BPA degradation with an impressive turnover frequency of 13.62 Lmin-1g-1. The system demonstrated good robustness, maintaining high performance across a broad pH window (3-9) and in the presence of common inorganic anions and complex water matrices. Mechanistic investigations including scavenging tests, probe experiments, and electron paramagnetic resonance (EPR) spectroscopy revealed that the catalytic degradation of BPA by SAC-Fe/PDS follows a synergistic nonradical pathway. In this pathway, PDS first reacts with atomically dispersed Fe-N X active sites on SAC-Fe to generate a surface-bound, high-valent iron-oxo intermediates, which is followed by the degradation of BPA by this active species. Additionally, the NC support in SAC-Fe also participates in PDS activation, promoting BPA degradation synergistically following the electron transfer process. Further investigation indicated this pathway also possesses superior selectivity toward representative emerging contaminants containing electron-donating groups.

Hard carbon stands out as a prime candidate material for high-performance lithium-ion battery anodes because of its distinctive structure. Yet, reconciling high capacity with superior rate capability in materials derived from low-cost precursors remains a significant challenge. In this study, we successfully synthesized a porous carbon material characterized by “bulk disorder and surface reconstruction” using anthracene oil pyrolysis carbon (AOPC) as a precursor. This porous material served as an electrode for lithium-ion batteries and was evaluated against commercial graphite under identical conditions. And the structure-activity relationship between its high capacity, superior rate capability and material is clarified. The results indicate that porous carbon materials demonstrate superior electrochemical performance compared to commercial graphite. Specifically, at 50 mA g⁻¹, it achieved a discharge capacity of 619.81 mAh g⁻¹(Second cycle discharge capacity), surpassing graphite’s 335.98 mAh g⁻¹. At 1 A g⁻¹, it maintained a capacity of 192.12 mAh g⁻¹, superior to graphite’s 53.53 mAh g⁻¹, showing excellent rate capability. The high reversible capacity and superior rate capability stem from the synergistic interplay among its unique disordered microstructure, large interlayer spacing, and extensive pore network, all of which synergistically support the lithium storage mechanism of hard carbon materials. The study converted low-value anthracene oil pyrolysis residue into hard carbon anode material, offering a scalable approach for producing cost-effective and effective lithium-ion battery anodes.

The chlorine content in PVC has a significant impact on the preparation of carbon nanocomposites through its pyrolysis. In this study, PVC was dechlorinated to different degrees, and Pre-treated PVC was mixed with a selfmade FeTiOx catalyst, and then subjected to catalytic pyrolysis in a microwave field, and FeTi/C nanomaterials with different carbon morphologic profiles were successfully prepared. Firstly, the kinetics of dechlorination during PVC pyrolysis was studied to reveal the nature of the dechlorination reaction and provide a scientific basis for the preparation of Pre-treated PVC with different chlorine content. The results show that the dechlorination process of PVC follows the first-order reaction model, and the average value of activation energy Ea of dechlorination stage is 142.70 kJ & sdot;mol- 1, and the average value of prefactor A is 1.67 x 1016 s- 1. Secondly, during the pyrolysis process, it was found that FeTiOx catalyst containing low-valent iron oxides after hydrogen reduction had better microwave absorption and heating performance than FeTiOx catalyst containing only high-valent iron oxides, which was more likely to promote the microwave pyrolysis process. When the chlorine content of Pretreated PVC was 0.41 wt%, the carbon material in FeTi/C was mainly carbon nanotubes, and the carbon yield was 33 wt%. As the chlorine content increased to 6.7 wt% and 13.78 wt%, the aromatization during pyrolysis was greater than the dehydrogenation of polyolefins, and the surface of the FeTiOx catalyst was passivated by an FeClx layer. The carbon material in FeTi/C was transformed into spheroidal amorphous carbon with a lower degree of graphitization, and the carbon yield was reduced to 20.69 wt% and 12.39 wt%, respectively. This paper proposes a method to prepare FeTi/C nanomaterials with different carbon morphologies by controlling the chlorine content in PVC under microwave catalytic pyrolysis conditions, providing a new idea for the efficient and harmless recycling of PVC.

In this study, a FeTi/CNT (FeTi/C-350) nanomaterial was prepared via pyrolysis of pre-treated PVC with a low chlorine content (0.41 wt%). It exhibited excellent phenol degradation performance in the Fenton-like system, achieving a degradation efficiency of 95.33% within 30 min under optimal conditions and retaining 91.11% efficiency after five cycles. The performance was significantly superior to that of spherical amorphous carbonbased FeTi/C materials obtained under high chlorine contents (6.7 and 13.78 wt%). Systematic characterization and mechanism investigation revealed that chlorine content could precisely regulate the morphology and graphitization degree of the carbon support. A low chlorine content induced the formation of FeTi/C-350 with a CNT support, which possessed advantages in specific surface area and pore structure. Benefiting from the high electrical conductivity of carbon nanotubes, the Fe2+/Fe3+ redox cycle was accelerated, and center dot OH and center dot O-2(-) were efficiently generated. Phenol mineralization was realized through the heterogeneous synergism among carbon nanotubes, Fe/Ti active sites, and reactive radicals. This study realized the synergy between high-value utilization of PVC solid waste and treatment of phenol-containing wastewater, providing theoretical support for the design of high-efficiency Fenton-like catalysts. The as-prepared FeTi/CNT nanomaterial shows promising application prospects in the treatment of organic pollutants such as phenol-containing coking wastewater.

The emerging field of contact-electro-catalysis (CEC) harnesses mechanical energy to drive chemical reactions via interfacial electron transfer triggered by contact electrification (CE). When integrated with ultrasound (US), US-initiated CEC achieves high efficiency under ambient conditions, presenting a sustainable alternative to conventional catalytic methods. This review provides a systematic analysis of US-initiated CEC, beginning with its fundamental electron-transfer-dominated mechanisms at liquid-solid interfaces, underpinned by key models such as the electron-cloud-potential-well and Wang’s hybrid electric double layer. Key factors governing performance, including catalyst properties, solution parameters, and US conditions, are critically evaluated. We further elucidate the synergistic physical and chemical effects of US, which enhances interfacial contact, mass transfer, and in-situ radical generation. Material design strategies progress from classic polymers and oxides to advanced composites, aimed at optimizing charge utilization. The significant applications in environmental remediation, resource recovery, chemical synthesis, and biomedical therapy are summarized, demonstrating the versatility and green chemistry attributes of this technology. Finally, persistent challenges in mechanistic understanding, material stability, and reactor scalability are discussed, alongside future directions centered on in-situ characterization, rational catalyst design, and process intensification. This review aims to advance US-initiated CEC from conceptual innovation toward practical implementation.

Historical gold-bearing metallurgical residues are increasingly important secondary resources as readily treatable gold ores become depleted. This study investigated an ancient ash-blowing slag containing 1.45 g/t Au, with gold recovery limited by dense silicate/iron-oxide encapsulation, residual carbonaceous matter, and coexisting heavy metals. To improve gold leachability, a NaOH–Na2SO3 assisted roasting pretreatment followed by leaching with a Jinchan lixiviant was evaluated. During roasting, NaOH promoted silicate/aluminosilicate network depolymerization, while Na2SO3 participated in sodium-assisted phase transformation. The dense slag matrix was partly converted into sodium-silicate-related phases, forming a porous roasted product and improving gold accessibility. BET analysis confirmed pore development, with the surface area increasing from 1.0191 to 2.6679 m2/g and the total pore volume from 0.004878 to 0.016910 cm3/g after roasting. Response surface optimization showed that roasting at 650 °C for 90 min with 15 wt% NaOH and 5 wt% Na2SO3 produced a gold leaching efficiency of 87.12 %. Further optimization of leaching conditions increased gold recovery to 91.09 % at 2 wt% lixiviant dosage, 50 °C, and 36 h. XRD, SEM–EDS, and BET analyses indicated that the improvement was mainly associated with roasting-induced phase transformation, pore development, and enhanced gold accessibility rather than simple thermal activation. Overall, the enhanced gold recovery was mainly attributed to sodium-assisted phase transformation, pore development, and improved accessibility of encapsulated gold to the lixiviant.

Indium and germanium are rare elements and contribute to supporting materials for contemporary high technology new materials. Research and development of efficient separation and extraction of indium and germanium have important practical significance. A new process of "one step extraction and stepwise stripping" is proposed in this work to coextract indium and germanium with D2EHPA-YW100 synergistic system of Di(2ethylhexyl) phosphoric acid (D2EHPA) and C7-9 hydroxamic acid (YW100) denoted by D2EHPA-YW100. In the coextraction process, 98.9 % of indium and 99.9 % germanium were extracted utilizing an organic phase consisting of YW100 (1.4 %), D2EHPA (15 %) and sulfonated kerosene (83.6 %). During the two-step stripping process, 99.9 % of indium was selectively stripped from the loaded organic phase in step-1 using 4 M HCl. In step-2, 99.5% of germanium was stripped using a 1 M NH4F solution. This separation resulted the enrichment of germanium concentration by 6-7 fold and indium concentration by 19 fold. This method has four advantages: (i) simplifies the separation process, (ii) reduces equipment investment by nearly 50 %, (iii) minimizes extraction agent loss, and (iv) reduces management and labor costs.

The study introduces a microwave-assisted rutile seed crystal (RS) method to synthesise mixed-phase TiO2 nanoparticles, controlling the rutile TiO2 (TiO2-R) phase content (gamma R) from 33.0 % to 99.3 % by adjusting the doping level of RS to 20.0 wt% in the metatitanic acid (MA). The sample, designated as MA-20, with the highest oxygen vacancy (Ov) concentration of 38.56 %, demonstrated over 99 % microwave absorption (minimum reflection loss (RL) -56.8 dB) and a heating rate of 0.836 degrees C/s under 2000 W and 20 g. RS enhanced the dielectric property of MA, facilitating phase transition from anatase TiO2 (TiO2-A) to TiO2-R above 600 degrees C, with critical temperatures between 800 and 1000 degrees C. MA-20, with a surface area of 1.9226 m2/g and pore size distribution of 9.0851 nm, showed that higher RS doping levels promoted phase transition and grain growth, thereby enhancing the crystallinity and charge transfer efficiency. More than 50 % of MA-20 particles were under 10 nm, and 94 % were below 100 nm, confirming the synthesis of TiO2 nanomaterials. MA-20 exhibited excellent electromagnetic wave storage and conversion properties. Adjusting microwave parameters and RS levels controls gamma R, offering an efficient approach for preparing mixed phase TiO2 catalysts, essential for semiconductor photocatalysis and overcoming TiO2-A limitations.

The presence of formaldehyde (HCHO) generally has a detrimental impact on the NH3-SCR process, leading to significant formation of the by-product HCN, which remains a major challenge. It was discovered that Mn-Co bimetallic oxides exhibited a very low HCN yield, with a maximum selectivity of only 5.4 % at 100 degrees C. Above 175 degrees C, almost no HCN was detected. Furthermore, HCHO exerts dual-temperature effects on the Mn-Co catalysts in NH3-SCR process. NOx conversion was minimally affected between 150-200 degrees C, a typical temperature range for most natural gas boilers. Above 250 degrees C, HCHO greatly facilitated NOx conversion, with the Mn1Co2Ox catalyst showing the highest increase in this range. Water vapor could mitigate the inhibitory effect of HCHO, promoting the catalytic hydrolysis of intermediate products and enhancing NOx conversion. Characterizations demonstrate that the superior redox ability, Lewis acidity, and abundant surface hydroxyl sites are essential for achieving efficient NOx conversion while suppressing HCN formation under the HCHO-laden NH3-SCR conditions. The inhibitory behavior at low temperatures stems from the blockage of the active sites by the intermediates such as HMTA, HCONH2 and formate, whereas its promotional effect at elevated temperatures originates from the catalytic hydrolysis of HCN into NH3 that subsequently reintegrates into SCR cycles. This work systematically deciphers the temperature-dependent mechanistic interplay between HCHO and NH3-SCR reactions, while identifying critical catalyst characteristics that mitigate HCN generation.

This study explores the coordination of Ethylenediamine Triacetic Acid chelating resin with U(VI)/Nd(III) via potentiometric titration, determining the protonation constants of H₃L and stability constants of H₃L—U(VI)/Nd(III) complexes. Batch experiments confirm complexes like UO₂HL, UO₂L⁻, UO₂(OH)L2⁻, NdHL⁺, and NdL. Fixed H₃L differs from free H₃L; adjacent carboxylic groups may form hydrogen bonds, enhancing lgβ₃. H₃L forms a tridentate coordination with U(VI). The competitive adsorption of U(VI) and Nd(III) within a pH range is calculated and verified. Additionally, U(VI) adsorption in the presence of citric acid is calculated, supporting practical applications.

Metal-organic frameworks (MOFs) are promising adsorption materials for emerging organic contaminants. However, their structure-activity relationship studies are often simplified, which hinders their broader environmental applications. In this work, Zr-MOF (MOF-808) was selected as a representative adsorbent to study its structure-activity relationship toward the adsorption of various emerging organic contaminants containing different functional groups such as carboxyl (-COOH), sulfonic acid (-SO3H), hydroxyl (-OH), and amino group (-NH2). It was found that the structure of organic functional groups in the contaminants significantly affected the adsorption selectivity of MOF-808, with the adsorption capacity decreasing in the order of -COOH > -SO3H > -OH ≈ -NH2. Linear solvation energy relation (LSER) was employed to analyze the adsorption mechanism and estimate the contribution of each descriptor. It was shown that the adsorption was governed by interactions in the order: electrostatic > π-π stacking, while hydrogen bonding was relatively weaker. This work provides insights into the structure-activity relationship between MOFs and emerging organic contaminants and may be useful for designing porous adsorbents.