Solid Transformation Research Articles

Mechanochemical Transformations of Pharmaceutical Cocrystals: Polymorphs and Coformer Exchange.

Transformations of solid samples under solvent-free or minimal solvent conditions set the future trend and define a modern strategy for the production of new materials. Of the various technologies tested in recent years, the mechanochemical approach seems to be the most promising.The aim of this review article is to present the current state of art in solid state research on binary systems, which have found numerous applications in the pharmaceutical and materials science industries. This article is divided into three sections. In the first part, we describe the new equipment improvements.A brief description of techniques dedicated to ex-situ and in-situ studies of progress and the mechanism of solid matter transformation is presented. In the second section, we discuss the problem of cocrystal polymorphism highlighting the issue related with correlation between mechanochemical parameters (time, temperature, energy, molar ratio,liquid assistant, surface energy, crystal size, crystal shape) and preference for the formation of requested polymorph. The last part is devoted to the description of the processes of coformer exchange in binary systems forced by mechanical and/or thermal stimuli. The influence of the thermodynamic factor on the selection of the best-suited partner for the formation of a two-component structure is presented.

A variational framework for Cahn–Hilliard-type diffusion coupled with Allen–Cahn-type multi-phase transformations in elastic and dissipative solids

This article presents a variational framework for coupled chemo-mechanical solids undergoing irreversible micro-structural changes at infinitesimal strains. The coupled problem is characterised by phenomena such as phase transitions, micro-structure coarsening and swelling. It is an extension of our previous work on variational inelasticity for a conserved chemo-mechanical setting to a unified conserved and non-conserved setting which include multi-phase transformations. The variational framework, again governed by continuous-time, discrete-time and discrete-space–time incremental variational principles, is outlined for coupled diffusion-phase transformation phenomena in elastic and dissipative solids. For the sake of simplicity, focus is restricted to isothermal conditions. It is shown that the governing macro- and micro-balance equations of the coupled problem appear as Euler equations of these minimisation and saddle point principles. In contrast to our previous work, extended variational principles (with the gradient of the chemical potential and phase fractions) are constructed that account for diffusion-phase transformation coupling. This is achieved by Legendre transformations. Note that the local–global solution strategy is still preserved and the resulting system of symmetric non-linear algebraic equations are solved by Newton–Raphson-type iterative methods. The applicability of the proposed framework is demonstrated by numerical simulations that qualitatively characterise lower bainitic micro-structure.

Steel mill solid waste transformation: Optimizing converter sludge recycling through RHF technology

Current methods for treating converter sludge include reintroducing it into the sintering or pelletizing process. However, this method leads to the enrichment of zinc in the blast furnace, which affects the stability of the production operation. To solve this problem, a direct reduction process utilizing multi-solid waste collaborative rotary hearth furnace (RHF) has been implemented in steel plants to recover and safely dispose of valuable components in waste. The laboratory results show that the dezincization rate of the metallized pellets is 99.12 % and the metallization rate is 80.51 % under the premise of reducing 50 °C by calcination at 1200 °C for 15 min in the nitrogen atmosphere. In the industrial test conducted in RHF production line of Shagang from March 2022 to August 2023, the temperature in the high temperature zone was reduced by 50 °C, and the time in the high temperature zone was controlled to 15 min. The industrial test results showed that the residual zinc content in the metallized pellets was 0.63 %, and the metallization rate was about 75.12 %. These particles can be used as feedstock or coolant in the steelmaking process. The average grade of by-product zinc oxide coarse powder can reach 65.88 %, which can be further processed into zinc products with remarkable economic benefit. Through RHF integrated management of converter sludge and other solid waste in steel mills, metallized pellets and high-value products can be produced, which can effectively reduce solid waste in steel enterprises and improve resource utilization.

A novel microgroove-based absorber for sorption heat transformation systems: Analytical modeling and experimental investigation

This study proposes a novel sorber bed design, a stationary thin film microgroove-based absorber, that can address the low specific power and oversized sorber bed issues in existing oscillatory solid sorption heat transformation systems. An analytical heat and mass transfer model is developed for the proposed stationary thin film microgroove-based absorber. A highly-wettable microgrooved aluminum substrate is fabricated by the deposition of a hybrid Al2O3/TiO2 layer, and experimental water uptake measurements are obtained using a custom-built gravimetric large pressure jump setup to validate the analytical model. The model examines how key design parameters affect specific cooling power, cooling power density, and energy storage density. Findings indicate that cycle time and groove depth significantly impact system performance. Also, it is found that there is an optimum groove depth, or film thickness, to achieve maximum power. Trapezoidal grooves achieve higher specific cooling power and cooling power density, while rectangular grooves yield a higher maximum energy storage density. It is experimentally shown that a specific cooling power enhancement of up to 600 % can be obtained compared to the experimental data available for oscillatory sorber beds. Also, the absorption rate of the present sorber bed is up to three times higher than that of falling film absorbers.

Solid carbonaceous materials transformation during pulverised coal and natural gas co-injection

Co-injection of coal and gaseous fuel, such as natural gas (NG), is common practice promoting pulverised coal gasification in blast furnace (BF) ironmaking. The high hydrogen content in NG makes it possible to act as cleaner reductant to reduce iron ore to produce hot metal, which will result in reduced CO2 emissions during the ironmaking process. In this work, selected parameters affecting the overall performance of the pulverised coal and natural gas co-injection system were studied using the CanmetENERGY injection test rig, including coal injection rate, natural gas rate and blast oxygen enrichment. Increase in combustion intensity promotes conversion of injected coal into solid carbonaceous material with relatively low reactivity with CO2. Hence, it reduces the competitiveness of combustion residues for oxygen in the raceway to continue the gasification process. NG co-injection reduces the coal combustion intensity but enhances the reactivity of combustion residues by competing the oxygen in the raceway.

Development of All Solid State Nanosecond Pulse Transformer Fault Detection Device Based on Marx Circuit

Abstract a nanosecond pulse generator with a fast leading edge for transformer fault diagnosis is developed. The device is composed of a full solid-state nanosecond pulse generator based on Marx circuit and with a tail cut switch and a field programmable logic gate array (FPGA) device. Among them, the nanosecond pulse source is mainly composed of DC power supply, control circuit and main circuit. The main circuit is a 9-level modular Marx circuit, using MOSFET as the main switch and tail cut switch; The control circuit generates a synchronous trigger pulse signal, which drives the MOSFET to work synchronously after being isolated through the optical fiber. The output nanosecond pulse voltage parameters are adjustable amplitude 0-8kv, pulse width 100˜1000ns, repetition frequency 1hz˜1000hz, rising edge 30ns and falling edge 40ns. The transformer fault diagnosis platform is built, and the transformer off-line and on-line fault diagnosis is carried out, which paves the way for further exploration of transformer fault diagnosis technology.

Solid waste slurry grouting transformation mechanism of loose sand layer based on slurry-water replacement effect

During coal mining, when loose water-bearing sand layers are exposed and connected, it is extremely easy to cause water and sand inrush accidents, threatening the lives and properties in mines. Because of the intricate and tortuous internal structure of the sand layer, the diffusion pattern of grouting slurry within the loose sand layer has not been accurately characterized. Improving the efficiency of grouting and reducing the cost of grouting are common difficulties faced by industrial and mining enterprises in the grouting renovation of loose water-bearing sand layers. This paper innovatively proposes the mechanism of slurry-water displacement effect based on the diffusion characteristics of grouting slurry within the water-bearing sand layer. It studies the power-law fluid seepage and diffusion mechanism of porous media tortuosity effect and slurry-water displacement effect and derives the spherical diffusion equation of power-law fluid seepage grouting considering the coupling of porous media tortuosity effect and slurry-water displacement effect. At the same time, an indoor experimental device considering the slurry-water displacement effect is designed to verify the rationality of the spherical seepage grouting diffusion equation considering the superimposed effects of the two. Furthermore, relying on the COMSOL Multiphysics platform, a three-dimensional numerical calculation model of the power-law fluid spherical seepage grouting mechanism considering the porous media tortuosity effect and slurry-water displacement effect is constructed. It analyzes the seepage and diffusion characteristics of power-law grouting slurry in water-bearing sand layers, and studies the influence of different porosity of loose water-bearing sand layers, spacing between slurry and water holes, grouting pressure, and slurry viscosity on the volume of loose water-bearing sand layers. The key factors affecting the volume of loose water-bearing sand layers are grouting pressure > spacing between slurry and water holes > porosity of sand layer > slurry viscosity. Compared with previous grouting technologies and processes, the slurry-water displacement grouting technology can solve the problems of small grouting diffusion range and poor grouting effect in high-pressure underwater water-bearing sand layers to a certain extent.

The Digital Evolution Strategies for Overcoming Cybersecurity and Adoption Challenges in French SMEs

French Small and Medium-sized Enterprises (SMEs) face a crucial juncture in their path towards digital transformation. They encounter notable obstacles in embracing digital technologies and bolstering cybersecurity measures. This integrative literature review examines the complex relationship between digitalization and cybersecurity, highlighting their importance for enterprises' ongoing competitiveness and operational security. The study is focused on two primary areas: the integration of digital technologies and the establishment of robust cybersecurity frameworks. This review thoroughly examines existing research to offer strategic insights for leaders of French SMEs and IT policymakers. It employs rigorous inclusion and exclusion criteria, detailed data extraction, and comprehensive synthesis to ensure a systematic analysis. The findings emphasize the critical roles of organizational culture and innovation diffusion in shaping the adoption of technology and the implementation of security practices. The review puts forward practical suggestions to address the digital divide, strengthen cybersecurity readiness, and promote a digital environment accessible to all sectors of French SMEs. These recommendations focus on enhancing operational efficiency, minimizing expenses, and fortifying the security framework to bolster a solid national digital transformation. The study's conclusions highlight the significance of these findings for future research and practice, providing a thorough guide for incorporating digital transformation and cybersecurity in the context of French SMEs.

The impact of ammonifying microorganisms on the stabilization and carbon conversion of cow manure and wheat husk co-composting

Ammonifying microorganisms (Amm) play a crucial role in the global utilization of agricultural solid residue, but the mechanism of their action in the stabilization and carbon transformation of agricultural solid residue composting remains unclear. In this work, different treatments, including Control, Amm-1, Amm-2, Amm-3, and Amm-4, were established for co-composting of cow manure and wheat husk to investigate the action mechanism of Amm in composting stabilization and carbon conversion. The findings indicated that the Amm inoculation facilitated the decrease of total organic carbon, dissolved organic carbon, CO2 productions, and CH4 emissions by 35.13 ∼ 37.28 %, 15.61 ∼ 16.78 %, 1.75 % ∼ 32.38 %, and 10.30 %∼ 18.01 %, respectively. Among the treatments. The inoculation of Amm-4 immensely showed the highest improvement effect on the organic solid residue humification and carbon transformation process, with the final compost product showed high stability and favorable performance on improving crop growth. Further mechanism analysis suggested that the Amm inoculation optimized humification-related enzyme activity and fungal community structure, enhanced the humus formation, increased the humification index, and promoted the stabilization of final product. In conclusion, this investigation verified the Amm inoculation can improve compost carbon conversion and promote the green application of agricultural solid residue as resource.

Reversible shape transformations through continuous deformations in soft responsive self-repairing solids using voxel techniques

Voxel modeling is a technique in which an object is represented by an array of cubes. One advantage in design-for-manufacturing is that selected voxels may be assigned desired responsive properties through additive manufacturing. It allows for achieving reversible shape transformation in soft responsive self-repairing solids within a strategic sequence. The first step in the sequence involves selecting an equivalent geometric shape. The second step involves mapping shapes to preserve properties during continuous deformation. The third step involves transforming the shape from one form to another. The fourth step involves defining changes in dimensions. The final step involves correlating the flow of stress with the stretch of the solid. This research also considers self-repair or self-healing as part of the transformation process because the splitting or joining of solids involves continuous deformation. The newly transformed shape can also be considered as the intermediate shape, or first shape for next transformation. This leads to a chain of shapes that are topologically equivalent, and interchangeable. The iterative steps involved in shape transformation finds applications in topology optimization, generative design, metastructures, among others. One application of shape transformation in these domains is that it serves as an alternative to material reduction techniques.

Multiscale modeling of non-catalytic gas-solid reactions applied to the hydrogen direct reduction of iron ore in moving-bed reactor

Direct hydrogen reduction (H-DR) is a promising technology for green ironmaking. Given the absence of commercial H-DR data, computational simulation is a powerful tool for engineering and overcoming the complexity of the system. This study develops a multiscale moving-bed reactor model to simulate non-catalytic gas-solid reactions and evaluate parameters at the pellet scale that hierarchically impact the performance at reactor scale. The reactor and solid particles are treated as coupled physical domains, enabling the computation of the solid transformations along both scales. Predictions for H-DR process highlight the substantial supply of H2 molar flow in enhancing reactor performance. A sensitivity multivariate analysis revealed the significant effect of pellet structural characteristics and gas inlet conditions on the process. Increased pellet porosity offers flexibility for process optimization, enabling the use of lower H2 percentages and temperatures. These findings provide valuable insights into optimizing H-DR process, improving energy efficiency, and better H2 utilization.

Concurrent hetero-/homo-geneous electrocatalysts to bi-phasically mediate sulfur species for lithium–sulfur batteries

Expediting redox kinetics of sulfur species on conductive scaffolds with limited charge accessible surface is considered as an imperative approach to realize energy-dense and power-intensive lithium-sulfur (Li–S) batteries. In this work, the concept of concurrent hetero-/homo-geneous electrocatalysts is proposed to simultaneously mediate liquid–solid conversion of lithium polysulfides (LiPSs) and solid lithium disulfide/sulfide (Li2S2/Li2S) propagation, the latter of which suffers from sluggish reduction kinetics due to buried conductive scaffold surface by extensive deposition of Li2S2/Li2S. The selected model material to verify this concept is a two-in-one catalyst: carbon nanotube (CNT) scaffold supported iron-cobalt (Fe-Co) alloy nanoparticles and partially carbonized selenium (C-Se) component. The Fe-Co alloy serves as a heterogeneous electrocatalyst to seed Li2S2/Li2S through sulphifilic active sites, while the C-Se sustainably releases soluble lithium polyselenides and functions as a homogeneous electrocatalyst to propagate Li2S2/Li2S via solution pathways. Such bi-phasic mediation of the sulfur species benefits reduction kinetics of LiPS conversion, especially for the massive Li2S2/Li2S growth scenario by affording an additional solution directed route in case of conductive surface being largely buried. This strategy endows the Li–S batteries with improved cycling stability (836 mA h g−1 after 180 cycles), rate capability (547 mA h g−1 at 4 C) and high sulfur loading superiority (2.96 mA h cm−2 at 2.4 mg cm−2). This work hopes to enlighten the employment of bi-phasic electrocatalysts to dictate liquid–solid transformation of intermediates for conversion chemistry batteries.

Oriented Growth for Efficient and Scalable Perovskite Solar Cells by Vapor–Solid Reaction

AbstractThe precise control and understanding of crystal orientation in perovskite polycrystalline films are crucial for the development of efficient and stable devices. However, achieving this control remains a significant challenge. Herein, a PbI2 oriented growth strategy is developed, combined with in situ vapor–solid reaction transformations, to achieve oriented growth of full‐vacuum perovskite films. Grazing‐incidence wide‐angle X‐ray scattering (GIWAXS) analysis revealed the general pattern of PbI2 oriented vapor growth and in situ vapor–solid reaction transformation in this two‐step process. The resulting preferred orientation has effectively reduced trap state density, optimizing the carrier dynamics. As a result, champion efficiencies of 22.11% (0.148 cm2), 20.60% (1 cm2), and 19.41% (5 × 5 cm2 mini‐modules) are achieved, which are the highest value for perovskite based on vapor–solid reaction. Additionally, the oriented growth method is applicable to a variety of guide layers and is extended to 30 × 30 cm2 film, demonstrating the universality and scalability of the method.

Photoacoustic detection of transient phase transformation of nanoparticles.

The controllable preparation of spherical micro/nano particles of various materials has been achieved via the technology of the laser synthesis and processing of colloids (LSPC) recently. However, there is limited in situ research on the evolution processes of nanoparticles in photothermal transient environments, such as solid-state crystal transformations and changes of state, which limits the understanding and application of LSPC. Photoacoustic (PA) signals are sensitive to the optical, thermal and elastic properties of the medium, and can be used to measure the thermal and spectroscopic properties of matter. In this paper, the PA signals generated by the interaction of the laser with the surrounding liquid medium (ethanol, water, glycerin, etc.) and nanoparticles (Ag, TiO2, CeO2, ZrO2, etc.) are studied when the tunable LSPC technique provides different photothermal conditions (such as thermal expansion, solid crystal transformation and evaporation). It is found that semiconductors with different bandgaps, as light absorbers, have the ability to selectively absorb laser beams of different wavelengths. By changing the wavelength, the PA intensity can be adjusted accordingly. In addition, based on the fast laser heating and tunable fluence characteristics of non-focused laser beams in LSPC technology, transient processes such as material phase transitions and changes of state can be excited separately by adjusting the laser fluence. Taking titanium dioxide as an example, the PA signals generated by laser selective excitation of A-R (anatase into rutile) phase transitions and rutile vaporization can be detected.

Assessing Eco-Friendly Alternatives: Composite Fibers and Recycled Plastics for Sustainable Impact and Efficiency

The chase for sustainability has driven awesome strides in composite fibers and recycled plastics, which have made viable options available in numerous areas. Composite fibers are known for their recordbreaking strength-to-weight proportions and capacity to serve numerous functions, that’s why they’re used all over from the automotive industry to aviation. But natural fibers are hydrophilic, so they do not mix well with hydrophobic matrices they need surface adjustments and fire retardant treatments to be utilized for composites to perform at their best. On the other hand, one of plastics’ most significant benefits is their recyclability, recycling programs can do a lot to tackle widespread plastic contamination. Recycling has positive environmental effects, but still there are major challenges when it comes to plastic recycling including contamination and all the different types of plastics that require sorting out. Promising answers can be offered to these issues through better approaches to sorting and recycling plastic waste. For instance, life cycle assessments and carbon footprint research are vital for deciding how much composite fibers influence the environment in comparison with conventional materials made from recycled plastics. In this study, we can see that all through their lifecycle composite fibers have been found to discharge minimal amounts of GHGs subsequently reducing energy use to reduce pollution. Similarly, the work on recycled plastics when compared with virgin ones lowers their impacts on the environment by saving landfills from plastic waste, reducing the demand for raw materials, and high in energy production techniques. In general terms, sustainable indicators are exceptionally imperative in ensuring that we make choices based on reliable information regarding environmentally sustainable practices and industrial applications that require solid and sustainable future transformation.

EFFECT OF STEEL’S THERMAL CONDITION ON THE TRANSFORMATION TEMPERATURES OF TWO HOT-WORK TOOL STEELS WITH INCREASED THERMAL CONDUCTIVITY

The aim of our study was to investigate how different thermal conditions affect the transformation temperatures of two hot-work steels with high thermal conductivity. We focused on two conditions: soft annealing, and quenching and tempering. Soft annealing results in a ferritic steel matrix with spherical carbides, while quenching and tempering result in a fully hardened and tempered martensitic matrix with secondary and tempering carbides. We analysed samples using a simultaneous thermal analysis (STA) and differential scanning calorimetry (DSC) to determine the transformation temperatures. Controlled heating and cooling allowed us to observe the energy changes associated with the phase transformations. The equilibrium temperatures were calculated using the CALPHAD method. Our study investigated the influence of thermal conditions on different transformation temperatures, including solidus/liquidus temperatures, austenite solid transformation temperatures (A1 and A3), austenite solidification temperatures and bainite and/or martensite transformation temperatures. A DSC analysis was used to quantitatively measure the transformation temperatures and energy absorption during the endothermic processes (austenite solid transformation and melting) and to study the energy release during the exothermic processes (solidification and transformation). The results showed that soft annealing reduced the solidification interval and the solidus temperature, while energy absorption increased during melting. Conversely, quenching and tempering reduced the austenite solid transformation temperatures and energy release during solidification, including δ-ferrite solidification.

Photocatalytic Hydrolysis-A Sustainable Option for the Chemical Upcycling of Polylactic Acid.

Plastic waste is a critical global issue, yet current strategies to avoid committing plastic waste to landfills include incineration, gasification, or pyrolysis high carbon emitting and energy consuming approaches. However, plastic waste can become a resource instead of a problem if high value products, such as fine chemicals and liquid fuel molecules, can be liberated from controlled its decomposition. This letter presents proof of concept on a low-cost, low energy approach to controlled decomposition of plastic, photocatalytic hydrolysis. This approach integrates photolysis and hydrolysis, both slow natural decomposition processes, with a photocatalytic process. The photocatalyst, α-Fe2O3, is embedded into a polylactic acid (PLA) plastic matrix. The photocatalyst/plastic composite is then immersed in water and subjected to low-energy (25 W) UV light for 90 h. The monomer lactide is produced as the major product. α-Fe2O3 (6.9 wt %) was found to accelerate the PLA degradation pathway, achieving 32% solid transformation into liquid phase products, in comparison to PLA on its own, which was found to not decompose, using the same conditions. This highlights a low energy route toward plastic waste upgrade and valorization that is less carbon intensive than pyrolysis and faster than natural degradation. By directly comparing a 25 W (0.025 kWh) UV bulb with a 13 kWh furnace, the photocatalytic reaction would directly consume 520× less energy than a conventional thermochemical pathway. Furthermore, this technology can be extended and applied to other plastics, and other photocatalysts can be used.

Direct imaging of shock wave splitting in diamond at Mbar pressure

Understanding the behavior of matter at extreme pressures of the order of a megabar (Mbar) is essential to gain insight into various physical phenomena at macroscales—the formation of planets, young stars, and the cores of super-Earths, and at microscales—damage to ceramic materials and high-pressure plastic transformation and phase transitions in solids. Under dynamic compression of solids up to Mbar pressures, even a solid with high strength exhibits plastic properties, causing the induced shock wave to split in two: an elastic precursor and a plastic shock wave. This phenomenon is described by theoretical models based on indirect measurements of material response. The advent of x-ray free-electron lasers (XFELs) has made it possible to use their ultrashort pulses for direct observations of the propagation of shock waves in solid materials by the method of phase-contrast radiography. However, there is still a lack of comprehensive data for verification of theoretical models of different solids. Here, we present the results of an experiment in which the evolution of the coupled elastic–plastic wave structure in diamond was directly observed and studied with submicrometer spatial resolution, using the unique capabilities of the x-ray free-electron laser (XFEL). The direct measurements allowed, for the first time, the fitting and validation of the 2D failure model for diamond in the range of several Mbar. Our experimental approach opens new possibilities for the direct verification and construction of equations of state of matter in the ultra-high-stress range, which are relevant to solving a variety of problems in high-energy-density physics.

Investigation of microstructural evolution in a hybrid additively manufactured steel bead

Abstract Motivated by the beneficial effects of friction stir processing (FSP) for microstructural grain refinement, equiaxed grain production, and minimizing metallurgical defects, additive bead (AB) produced by the gas metal arc welding-wire arc additive manufacturing (GMAW-WAAM) technique was subjected to FSP. This was because deposited additive bead often develops defects such as shrinkage, voids, solidification cracking, during liquid to solid transformation. In this study, a low carbon steel double pass additive bead with 32 % lateral overlap was fabricated by the GMAW-WAAM technique followed by hybridization through FSP in the overlapped region (OR). The peak temperature estimation during bead deposition and FSP on bead was done through modeling by using ABAQUS. The microstructural analysis was carried out by using optical microscopy, scanning electron microscopy, electron backscattered diffraction, and transmission electron microscopy. The microstructure of OR of deposited additive bead is dominated by a combination of ferrite and bainite while that of hybrid additive bead (HAB) is dominated by a combination of ferrite and martensite. Further, the analysis revealed the effects of FSP on the OR in the form of grain refinement from 5.56 µm to 3.50 µm and a decrease in the low angle grain boundaries from 35.4 % to 10.6 %. The continuous dynamic recrystallization is observed since the bainitic fraction in the overlapped region decreased along with an increase in the fraction of martensite in the friction stir processed zone. The kernel average misorientation is observed to decrease after FSP from 1.001 of AB to 0.608. The microhardness test reveals the decrease in the hardness after FSP.

Enhancing the Immobilization of Hexavalent Chromium by the Interlayer Anion Adsorption of the Brucite-Transformed LDH in the Presence of Aluminum Ions

Current studies of chromium adsorption kinetics at the solid–liquid interface often neglect the influence of coexisting ions in complex wastewaters. Thus, it is critical to explore the hexavalent chromium Cr(VI) adsorption kinetics of solid-phase brucite (Mg(OH)2) in liquid-phase wastewater containing coexisting aluminum ions (Al(III)). This paper reveals that the presence of Al(III) significantly enhanced the Cr(VI) adsorption efficiency onto Mg(OH)2, with a peak of up to 91% compared to 5% for the absence of Al(III). The main reason for this enhancement was the initial surface ternary complexation of Mg(OH)2 and the cationic (Al(III)) isomorphic substitution to form Mg(II)-Al(III) layered double hydroxides (LDH), which also indicates a solid-phase transition on the surface of Mg(OH)2, which led to electrostatic adsorption in the gallery and made Cr(VI) immobilized and not readily released. Further calculation and analysis of the adsorption energy confirmed the mechanism of Cr(VI) adsorption. It was also concluded that Cr(VI) migration in Mg(OH)2-containing minerals was affected by the phase transformation of solids in the presence of Al(III). Hence, this study not only reveals the adsorption mechanism during the treatment of composite pollutant wastewater but also provides the methodological reference for brucite synergistic adsorption to remove heavy metal ions and purify and treat complex polluted wastewater.