Silicon-containing anodes often fail due to severe mechanochemical degradation driven by non-uniform lithiation and stress concentration. Here, we develop a scalable gradient nanoconfinement CVD strategy at the 2.2 kg batch scale that converts a robust microporous carbon (MC) scaffold into an active 3D nanoreactor, enabling uniform internal confinement of ultrafine amorphous nano-Si. Subsequent acetylene-derived carbon coating builds a structure-within-a-structure buffering architecture that promotes more homogeneous lithiation and mitigates stress accumulation. A multiscale 1D-2D-3D characterization workflow, complemented by synchrotron nano-computed tomography (nano-CT), supports the absence of Si-rich agglomeration at the particle scale. To establish causality beyond electrochemistry, three stepwise controls are employed: a ball-milled MC/Si-C benchmark (conventional mixing), a constant silane-flow MC@Si-C-const sample (without kinetic grading), and a non-porous artificial graphite host (AG@Si-C), collectively isolating the roles of vapor-phase growth, gradient delivery, and microporous confinement. As a result, electrode thickness growth is suppressed to 24.71% (after 20 cycles at the delithiation state) and a comparatively stable, LiF-enriched solid-electrolyte interphase (SEI) is observed. The concept is further demonstrated in 1.5 Ah NCM811||MC@Si-C/graphite pouch cells, delivering 80.02% capacity retention after 1933 cycles under clamped operation, and stable cycling to 1691 cycles without external mechanical constraint. These results highlight the practical feasibility of gradient nanoconfinement as a scalable route to translate nanoscale spatial control into durable pouch-cell performance.

With the increase in the demand for electronic-grade high-purity silane in the semiconductor chip industry, it is of great significance to develop a green and economical method for silane production. Therefore, a novel energy-saving fixed-bed process was proposed innovatively. In this paper, the thermodynamics and kinetics of the trichlorosilane disproportionation system were studied, and the optimal reaction conditions for the resin catalyst were determined, which were used for the subsequent simulation. Based on the conventional DR1 + DR2 process (which includes one trichlorosilane disproportionation reactor (DR1) and one dichlorosilane disproportionation reactor (DR2)), by adding an additional disproportionation reactor to the TCS recycle loop and/or DCS recycle loop, three improved process configurations were designed, including 2DR1 + DR2, DR1 + 2DR2, and 2DR1 + 2DR2 processes. Then, combined with four-column heat integration, the HI + 2DR1 + 2DR2 process was proposed to solve the bottleneck problems of high energy consumption and large circulation flow rate. The results show that the HI + 2DR1 + 2DR2 process achieved the best energy-saving effect. The TCS recycle loop flow rate reduced by 36.87%, the DCS recycle loop flow rate reduced by 12.41%, total energy consumption decreased by 62.8%, and CO2 emissions decreased by 56.72%. The unit energy consumption is 13.8 kg steam/kg SiH4, and the silane purity is greater than 99.9999%. This design can be easily applied to the existing production process of the silane plant, achieving energy-saving and low-cost production of silane.

Improving the separation efficiency between methyldichlorosilane (CH3SiHCl2) and trichlorosilane (SiHCl3) is one of the key urgent problems to be solved for the quality improvement and consumption reduction in high-purity polysilicon. In this work, three types of porous supported catalysts were prepared via an in situ reaction method, taking aluminum chloride (AlCl3) as the active component and activated carbon, silica gel and activated alumina as support; the catalytic reaction mechanisms of CH3SiHCl2 and silicon tetrachloride (SiCl4) over the as-prepared porous supported catalysts were investigated, based on density functional theory (DFT). The results reveal that among the three supported catalysts, the activated carbon-supported aluminum chloride catalyst (C@AlCl3) possesses the maximum binding energy (−3.20 eV) between the active component and support. CH3SiHCl2 and SiCl4 possess the lowest co-adsorption energy (−1.8 eV) and the minimum reaction energy barrier (0.8 eV) on C@AlCl3, accompanied by the maximum charge transfer to the catalyst surface (−2.65 e and −2.80 e), thus exhibiting the highest catalytic activity, with the maximum single-pass conversion of CH3SiHCl2 exceeding 90%. This work provides material basis and theoretical guidance for constructing a reactive distillation strategy for high-efficiency and low-energy separation of CH3SiHCl2 from SiHCl3.

Silicon (Si)-based materials are prime candidates for superseding conventional graphite in next-generation lithium-ion batteries (LIBs) owing to their exceptional theoretical specific capacities. Nevertheless, their commercial viability is hindered by massive volumetric fluctuations during cycling. Herein, two core-shell composites, Si@acetylene-derived carbon (Si@ACC) and Si@glucose-derived carbon (Si@GCC), were synthesized via chemical vapor deposition (CVD) and hydrothermal-carbonization processes, respectively. The differences between the two carbon shells and their impacts on electrochemical performance are systematically compared. Notably, the carbon layer prepared by the CVD strategy enables a high initial Coulombic efficiency (ICE) of 95.98%. In this core-shell design, the conformal carbon shell buffers expansive stresses while providing rapid electron transport pathways, thereby improving structural integrity and accelerating electrochemical kinetics. The Si@ACC electrode retains 66.33% of its capacity after 300 cycles at 1.0 A g-1. Moreover, a full-cell with a Si@ACC/graphite anode is assembled, delivering an ICE of 83.78% and a capacity retention rate of 66.49% over 200 cycles. Our strategy involves a simple synthesis process to prepare anode material that exhibits improved cycling stability and offers a promising pathway toward realizing the commercial potential of Si anodes for advanced LIBs. Simple CVD and hydrothermal methods greatly improve cycling stability.Systematically compare the physical structure and electrochemical performance of silicon-based anode materials prepared by CVD and hydrothermal methods.The assembled Si@ACC/Graphite||LiNi0.6Co0.2Mn0.2O2 (NCM622) full-cell demonstrates a high capacity retention rate and average Coulombic efficiency.

Conventional adsorbents used for removal of trace phosphine from recycled off-gas in polysilicon production often suffer from limited breakthrough capacity and rapid deactivation under oxygen-free conditions. In this work, a nitrogen-doped TiO2-supported Cu-based adsorbent (CuxNy@TiO2) was synthesized using a simple one-pot solid-state route to enhance PH3 removal performance. Nitrogen incorporation effectively regulates the surface chemical and electronic properties of TiO2, resulting in improved dispersion and stabilization of CuO species, enhanced surface basicity, and increased abundance of reactive surface oxygen species. Under an inert N2 atmosphere at 30 degrees C, the optimized Cu20N10@TiO2 exhibited a high PH3 breakthrough capacity of 204.7 mg & sdot;g-1 outperforming the undoped counterpart. Density functional theory calculations revealed that PH3 could be readily activated on CuO surfaces through a low-energy stepwise dehydrogenation pathway, facilitating subsequent oxidation by lattice and chemisorbed oxygen species. Regeneration experiments demonstrated that the adsorbent retained 86.6% of its initial capacity after three cycles. This study proposes a cost-effective strategy for designing robust Cu-based adsorbents and offers mechanistic insights into adsorption-oxidation processes relevant to industrial gas purification. and a breakthrough time of 2280 min at a weight hourly space velocity of 24,000 h-1, significantly

Polysilicon is widely used in the photovoltaic and semiconductor industries. The presence of trace phosphorus impurities in the trichlorosilane feedstock can severely degrade the quality of polysilicon products. To address the urgent need for complete phosphorus removal of trichlorosilane, in this work, on the basis of the reducing ability of PCl3 and the stronger Lewis base properties of its oxidation product, POCl3, we developed an efficient material, xMo/Al2O3[y], using Al2O3 as the support and Mo species as active substances through a simple and straightforward method. Under the optimized preparation conditions of 7.8% Mo loading and a calcination temperature of 450 °C, the adsorbent exhibited optimal performance in an organic system simulating a trichlorosilane system with a P adsorption capacity of 53.52 mg g−1, achieving near-complete elimination of phosphorus impurities. A series of characterization analyses suggested the following primary removal mechanism: initial oxidation of PCl3 to POCl3 by Mo6+ species, followed by its complexation with Mo sites via Lewis acid-base interactions. Furthermore, surface morphology damage during the removal process and the accumulation of reaction products on the spent adsorbent are the main factors contributing to its deactivation. This work presents an effective strategy for the deep dephosphorization of trichlorosilane.

Conventional extractive distillation for ternary azeotrope separation suffers from excessive entrainer consumption, high energy demand, and capital costs. Process intensifications, such as heat-integrated distillation and topwall dividing wall columns, have emerged to mitigate these limitations. However, these methods fail to address the fundamental challenge of coupling multiple extraction processes. To overcome this limitation, this study proposes an extractive middle-wall dividing wall column process (E-MDWC). The E-MDWC integrates two extractive processes, with the entrainer fed above the dividing wall, altering flow patterns and enhancing the mass-energy transfer in the column. This not only enhances separation efficiency but also reduces operating costs. In this paper, the COSMO-SAC model was employed to screen [BMIM][OAc] as the optimal entrainer for separating acetonitrile-ethanol-water azeotropes. The E-MDWC process was optimized using the NSGA-II to minimize the total annual cost (TAC) and COQ emissions. Compared to the conventional ternary extractive distillation process and the extractive top-wall dividing wall column process, the E-MDWC achieves reductions in TAC by 13.06 % and 9.43 %, and in COQ emissions by 10.45 % and 7.53 %, respectively, highlighting its superior performance. This study highlights the potential of E-MDWC as an advanced, economical, and sustainable solution for separating complex ternary azeotropes, particularly when utilizing low-volatility entrainers.

Reactive distillation enhances operational efficiency and reduces capital investment by synergistically coupling reaction and separation. However, its application is fundamentally limited in systems where the thermodynamic requirements for reaction and separation are incompatible. This study proposes an integrated strategy that combines a distillation column with a tubular fixed-bed reactor system for cumene production, achieving efficient reaction-separation coupling without altering the high-temperature and high-pressure reaction conditions. A systematic design methodology is developed, encompassing process synthesis, multi-objective optimization, exergy analysis, and dynamic control. Enhancements to the multi-objective particle swarm optimization algorithm enable a quantifiable trade-off between maximizing main product selectivity and minimizing total annual cost, providing decision support for industrial multi-objective optimization. A dynamic control scheme is further established, featuring redesigned inventory control loops to mitigate snowball effects and a multi-temperature control scheme ensuring product composition stability. PID parameters of critical controllers are optimized to alleviate oscillations in manipulated variables. This study provides a systematic solution for systems with mismatched reaction and separation conditions, offering significant theoretical and practical guidance for the green and efficient production of high-value chemicals.

Catalyst deactivation due to trace phosphorus impurities poses a major challenge in high-purity monosilane (MS) production. This study systematically elucidated the dual deactivation mechanism of phosphorus impurities through comprehensive experiments and characterizations. To address the deactivation issue, we developed an innovative Phosphorus-Control Adsorption-Coupled Reactive Distillation (PC-ACRD) process. The core mechanism of the PC-ACRD process includes an upstream phosphorus-selective adsorption unit (R01) designed to remove catalyst poisons from the feed stream. This preventive strategy significantly mitigates the adverse effects of phosphorus contaminants on the catalyst, thereby considerably extending the catalyst's operational lifetime from 24 months to 80 months. Moreover, the novel dual reactive distillation column arrangement (RD-T01/RDT02) integrates reaction and separation processes by segmenting the reaction stages, thereby enhancing the overall system efficiency. Both the traditional multi-column reactive distillation (RDMC) and the novel PC-ACRD process were systematically optimized using the Mesh Adaptive Direct Search (MADS) algorithm to minimize production costs. Compared to the RDMC process, the PC-ACRD process significantly reduced the unit production cost (UPC, $/kg) of MS by 39.8-47.5 % and energy consumption by 16.4-37.4 %. These improvements are supported by a comprehensive techno-economic and environmental assessment, which attributes the enhanced performance to improved phosphorus impurity removal and reaction efficiency. This research provides a robust theoretical foundation and an effective engineering solution for mitigating catalyst deactivation in high-purity MS production, offering substantial economic and energy-saving benefits that support the sustainable development of the photovoltaic industry.

The production of methyl lactate (ML) via esterification is a crucial intermediate unit in the lactic acid (LA) purification, typically conducted using reactive distillation. However, conventional configurations face challenges including reaction-separation temperature mismatch, impurity interference, and high energy demands for methanol recovery. To address these issues, this study proposes a side-reactor dividing-wall column (SRDWC) that decouples reaction and separation stages. The process was optimized via a penalty function-based particle swarm optimization algorithm to efficiently solve the resulting mixed-integer nonlinear programming problem, with key decision variables including the tray locations connecting the column and the reactor in both directions. The optimized single side-reactor SRDWC achieved an ML yield of 99.56% and reduced the reboiler duty by 55.24% relative to the esterification section of the dual reactive dividing-wall column reported by a previous study, demonstrating substantial potential for intensifying not only LA purification but also other complex reaction-separation systems suffering from temperature mismatch.

Reactive distillation (RD) offers substantial advantages for equilibrium reactions like esterification, due to its energy efficiency and process simplicity. However, its application is limited when azeotropes form between products and reactants, preventing the attainment of high-purity products. This study proposes coupling extraction with RD to disrupt azeotropic mixtures and enable the efficient removal of products. Using the synthesis of methyl propionate (MP) as a model system, a circulating tubular reactor is designed and introduced to measure the macroscopic kinetics of heterogeneous systems, providing essential data for process design. After a comparative analysis, dimethyl sulfoxide (DMSO) is selected as the solvent for this system. The multi-objective particle swarm optimization (MOPSO) algorithm is employed to optimize the reactive-extractive distillation (RED) process, to minimize the total annual cost (TAC) and CO2 emission. The optimal process achieves a purity and yield rate of product MP that both exceed 99.50 %, demonstrating that the extraction-coupled RD strategy offers a feasible and effective approach for addressing multi-azeotropic systems and overcoming the limitations of conventional RD techniques. This study indicates the difference between intrinsic and macroscopic kinetics by experiments and simulation, providing a critical theoretical foundation for the scale-up design and process optimization of industrial reactive distillation.

Silicon (Si) is regarded a leading anode material for high-energy-density lithium-ion batteries (LIBs). However, the significant volume change (>280%) restricts its industrial development. Embedding Si nanoparticles (Si NPs) into a porous carbon (PC) framework via fluidized-bed chemical vapor deposition (FBCVD) is an effective approach to mitigate the volume expansion of Si. In this study, the effects of the silane (SiH4) pyrolysis temperature, SiH4 pyrolysis time, and the ratio between the gas velocity and the minimum fluidization velocity (U/U-mf) in the fluidized bed on Si carbon anode materials (Si@C) were investigated. These findings reveal that a lower SiH4 pyrolysis temperature can result in the formation of amorphous Si, which can mitigate the volume expansion of Si. In addition, the SiH4 pyrolysis time influences the Si content. A moderate Si content can balance the capacity and cycle life. In addition, the U/U-mf in the fluidized bed affects the integrity of the carbon coating. A suitable U/U-mf can enhance the integrity of the carbon coating. Furthermore, under the optimal parameters, the half-cell with the Si@C-1 electrode delivers a high capacity of 1859.9 mAh g(-1) and a high ICE of 90.6%; after 100 cycles, it retains a capacity of 1329.7 mAh g(-1), corresponding to a retention rate of 83.9%. For the full cell, the Si@C-1 electrode has a capacity retention rate of 82.2% after 150 cycles, demonstrating excellent cycling stability. This study on the effects of these parameters can serve as a valuable reference for industrial scale-up and practice.

The existing forms and evolution mechanisms of carbon impurities constitute the core scientific issue in the optimization of polysilicon purification processes. The depth of research on this issue directly determines the targeting and effectiveness of directional impurity removal strategies, and is even a key prerequisite for improving the quality and reducing the cost of polysilicon products. Based on HSC simulation calculations and using the Gibbs free energy of reactions as the judgment criterion, this paper investigated the existing forms and evolution mechanism of carbon impurities during the production of polysilicon via the modified Siemens process. The results show that the evolution mechanism of carbon impurities is as follows: the solute carbon in silicon powder reacts with hydrogen to generate CH4. Subsequently, CH4 synergistically undergoes radical rearrangement and the Rochow reaction with methylchlorosilanes in chlorosilane and CH4 in recovered hydrogen. Meanwhile, CH3· radicals combine with radicals generated from chlorosilanes to form a mixture of methylchlorosilanes dominated by SiH(CH3)Cl2 as well as CH4. After distillation purification, SiH(CH3)Cl2 enters the SiHCl3 stream, and then synergistically undergoes cracking and radical rearrangement with CH4 in high-purity hydrogen, the solid-soluble elemental carbon forms and deposits in polysilicon. Simultaneously, a mixture of methylchlorosilanes dominated by SiH(CH3)Cl2 along with CH4 is generated and then fed into the tail gas system. This will provide the necessary theoretical foundation for the development of efficient and low-cost impurity removal strategies.

Photochemical reactions offer advantages for enabling chemical transformations under mild conditions with low energy consumption. However, their low conversion rates in reactors lead to increased production costs and limited industrial application fields. This study overcomes these limitations by developing a side-reactor column distillation (SRC) process that integrates reaction and separation, achieving continuous quadricyclane production with enhanced conversion efficiency. Process parameters are optimized using particle swarm optimization under a 99.9 mol% product purity constraint, achieving enhanced operational stability and economic performance. Three dynamic control structures are subsequently proposed based on the optimized process to enhance disturbance robustness. When subjected to +/- 10% feed flowrate disturbances, the temperature-composition cascade control structure (CS3) demonstrates superior performance relative to alternative structures, achieving 36% faster steady-state recovery with minimized product purity fluctuations. Integral squared error analysis confirms the superior disturbance rejection capability of CS3, establishing it as the most robust control scheme. The research expands SRC applications and provides a practical approach to deploy robust control strategies industrially.

The research and development of reactive distillation process with low condensation cost have always been the focus of attention in the field of trichlorosilane disproportionation. Therefore, an economical and feasible process of silane production is developed in this paper to provide reference for the industrial application of trichlorosilane disproportionation in RD. Firstly, the thermodynamic properties of trichlorosilane disproportionation system were investigated, and the catalysts with stable activity were screened for subsequent simulation and Industrial production. Based on the conventional reactive distillation (CRD) process, the reactive distillation with intermediate condenser (RD-IC) process was proposed to reduce the duty of the overhead condenser. Besides, the reactive pressure-swing distillation (RD-PS) process was proposed to increase the tower top temperature. Besides, a novel reactive distillation with multistage condensation (RD-MC) process combining RD-IC and RD-PS was developed to prepare silane. Furthermore, the four proposed process models were analyzed from three different perspectives: economic cost, thermodynamic efficiency and environmental friendliness. Compared with the traditional reactive distillation process, the proposed multi-stage condensation reactive distillation process reduced TAC by about 64%. Finally, the feasibility and accuracy of the reactive distillation with multistage condensation process for chlorosilane disproportionation were verified through industrial production experiment and equivalent simulation.

In this study, an acid-modified Cu–Ce/HZSM-5 bimetallic adsorbent was developed for the removal of trace PH 3 impurities from simulated recycled hydrogen in a chemical vapor deposition furnace for polysilicon production.

There is an urgent need for efficient and cost-effective adsorbents for the removal of trace hydrogen phosphide (PH3) from the circular hydrogen systems in the polysilicon chemical vapor deposition furnaces. In this study, a straightforward and cost-effective method was used to synthesize a highly efficient adsorbent (Cex-Cuy/TiO2) for PH3 removal using TiO2 as the carrier and CuO as the active substance. Experimental findings demonstrated that optimal Ce doping amounts (nCu:nCe = 20:1) markedly enhanced the adsorbent's performance, with an adsorption capacity reaching as high as 149.14 mg g-1. Material characterization results indicated that Ce positively influenced the uniform dispersion of Cu on the TiO2 surface, and Ce doping increased the adsorbed oxygen content of the adsorbent, consequently enhancing its oxidation performance. The investigation of the reaction mechanism and causes of adsorbent deactivation revealed that the depletion of active substances (CuO) in the adsorbent and the accumulation of products such as Cu3P and phosphates are the primary factors contributing to its deactivation. Furthermore, high-temperature calcination could restore the activity of the adsorbent, indicating its great potential for engineering applications.

To enhance polysilicon purity by removing diborane (B 2 H 6 ) impurities from recycled hydrogen (H 2 ) in the production of polysilicon, a strategy involving the use of an adsorbent developed from activated carbon (AC) impregnated with xylitol was implemented. The adsorption breakthrough time and B2H6 breakthrough adsorption capacity for the adsorbent Xylitol-AC, under optimal xylitol impregnation conditions, were determined to be 570 min and 8.45 mg & sdot; g - 1 , respectively. The importance ranking of various impregnation conditions on adsorption characteristics was analyzed through Grey relational analysis (GRA). Analyses such as SEM-EDS, BET, FT-IR, CO2-TPD, XRD, XPS, and Raman spectroscopy indicated that the presence of abundant -OH groups in Xylitol-AC plays a pivotal role in its effective B2H 6 adsorption capability. The mechanism for B2H 6 adsorption by Xylitol-AC involves the interaction between B2H 6 and -OH groups, resulting in the formation of B(OR) 3 , B - (OR) 4 , and H2.

An Au/Mn 3 O 4 catalyst derived from Mn-MIL-100 exhibits a high catalytic performance for trace PCl 3 oxidation with oxygen in an organic system through an MvK-style supply of oxygen.

Usually, the ion implantation gases used in semiconductor production are required to be extremely high in purity. Due to the presence of trace CO2 in electronic special gas BF3, the quality of the material is significantly affected, which makes it crucial to impose control on CO2 content. Unlike a series of blank adsorbents reported in other studies, the zinc-loaded adsorbents prepared in this study are intended for the adsorption of CO2 from CO2/BF3. Firstly, the materials were characterized by XRD, BET, SEM-EDS and TG-DSC analysis, etc., and the breakthrough curves of the adsorbents as obtained under different preparation conditions were investigated at 20 °C and 200 kPa. The results show that the adsorption performance reached the optimal level when the activation temperature was 450 °C and a 13X molecular sieve was impregnated by 0.15 mol/L Zn(NO3)2. Moreover, compared with the Zn-13X, the breakthrough time was reduced to 69% and 44% in two adsorption cycles, respectively. Finally, FTIR was used to reveal the adsorption mechanism of the carbonates produced by CO2 adsorption. It was found that the adsorption performance was affected by the irreversible reduction in the number of active sites due to the continuous formation of polydentate carbonate during adsorption and regeneration.