Rich Porous Structure Research Articles

Preparation and electrochemistry study of a new Ti-based PbO2 electrode with Ta-Ti-Sn(Ru)Ox interlayer in Cu electrowinning

Copper (Cu) is a crucial non-ferrous material, and in this research, a new composite layered anode, Ti/Ta-Ti-Sn(Ru)Ox/PbO2, was developed for the hydrometallurgical process. The anode was created using thermal decomposition and subsequent electrodeposition, with Ti serving as the matrix and Ta-Ti-Sn(Ru)Ox as the interlayer. The study identified that the optimal molar ratio of Ta:Ti was 4:1, the ideal number of coating layers was 3, and the preparation temperature was 550 °C. The addition of Sn element improved the bonding force of the coating, preventing it from detaching even if it fails, while the inclusion of Ru enhanced the electrode’s service life. Moreover, the deposited PbO2 layer demonstrated a rich porous structure. In a long-cycle copper electrodeposition application, anodes with optimal preparation parameters showed higher current efficiencies and reduced energy consumptions compared to the Ti/Sn-SbOx/PbO2 baseline electrode, energy consumption reduced by 220.8 kWh per ton of copper product. This research presents a valuable strategy for designing and constructing high-performance electrodes for nonferrous electrolysis and other similar applications.

A shape-stable phase change material for high-temperature thermal energy storage based on coal fly ash and Na2SO4-K2SO4

Using coal fly ash (CFA) as the skeleton material and binary sulfates of Na2SO4-K2SO4 as the phase change material (PCM), high-temperature coal fly ash based phase change thermal storage materials (CPCM) were successfully synthesized. The influences of CFA fractions and types on the morphology, physicochemical properties, and thermal characteristics of the composites were intensively investigated. Results show that the heat storage density and thermal conductivity of CPCMs increase with the PCM content. Particularly, the CPCM60-A composite, comprising 60 wt% Na2SO4-K2SO4 eutectic and 40 wt% CFA-A, exhibits excellent chemical compatibility and stable shape retention after sintering. Furthermore, CPCM60-A demonstrates the highest phase change latent heat of 60.43 J/g and thermal conductivity of 0.61 W/(m·K). The influence of CFA types reveals that CFA-A with a higher ratio of SiO2 and Al2O3, lower carbon content, and a rich porous structure is more suitable to fabricate molten salt heat storage materials. This work demonstrates that CFA, a byproduct of coal-fired industry, is a promising skeleton material for the fabrication of high-temperature CPCM composites, offering a novel approach for enhancing the efficiency and cost-competitiveness of solar power and waste heat recovery systems.

Utilizing porous carbon composites based on biomass for lithium battery negative electrodes

This work used high-temperature calcination techniques along with basic chemical processing to produce a range of porous carbon compounds from biomass. After that, these substances were employed as anodes in lithium-ion batteries. The first hard carbon was produced via the dehydration reaction of strong sulfuric acid with sucrose (R-HC), then annealing in an NH3Ar environment was used to obtain the nitrogen-doped porous hard carbon (N-HC). Because N-HC has a high interlayer spacing (ca. 0.39 nm) and an abundant ultra-microporous structure (pore size < 0.75 nm), the lithium-ion diffusion coefficient in N-HC can reach up to 9.0 × 10−8 cm2.s−1. The obtained porous carbon compounds contain a rich pore structure, many functional groups, and a high specific surface area, according to the results. Following their application to the anode of lithium-ion batteries, they demonstrate favorable cycle stability and electrochemical performance. Furthermore, a detailed investigation into the kinetic characteristics of the lithium-ion diffusion behavior in the electrodes revealed that the porous carbon materials’ electrodes exhibited greater surface diffusion behavior for Li+.

Self-assembled chromium-based nitrogen carrier for chemical looping ammonia synthesis

Industrially, ammonia is generated mainly using the energy-intensive and CO2-emitting Haber-Bosch process, which is not conducive to sustainable economic and social development. The chemical looping ammonia synthesis (CLAS) is capable of coupling green energy, which is one of the available alternatives to the Haber-Bosch process, but the ammonia production rate of most of its nitrogen carriers is unsatisfactory. In this work, we designed a self-assembled nitrogen carrier using ZSM-5 molecular sieve (ZSM-5) and nickel (Ni) to modify chromium nitride (CrN). ZSM-5 molecular sieves have a rich pore structure, which enables the gas-phase reactants to react with the lattice nitrogen in the subsurface layer of the nitrogen carrier. Nickel can facilitate the dissociation of hydrogen during hydrogenation due to its higher hydrogen affinity. The ammonia production rate of the nitrogen carrier can reach 451.2 μmol g−1 h−1 at 700 °C and atmospheric pressure, and be able to remain 358 μmol g−1 h−1 after eight cycles. Furthermore, we also propose a full-coverage design strategy for nitrogen carriers: simultaneous optimization of the chemical and mass transfer processes in the nitrogen carrier. This work advances the design of high-performance nitrogen carrier, thus facilitating the applications of CLAS for the distributed ammonia synthesis.

A 3D bioprinted antibacterial hydrogel dressing of gelatin/sodium alginate loaded with ciprofloxacin hydrochloride.

Skin plays a crucial role in human physiological functions, however, it was vulnerable to bacterial infection which delayed wound healing. Nowadays, designing an individual wound dressing with good biocompatibility and sustaining anti-infection capability for healing of chronic wounds are still challenging. In this study, various concentrations of the ciprofloxacin (CIP) were mixed with gelatine (Gel)/sodium alginate (SA) solution to prepare Gel/SA/CIP (GAC) bioinks, following the fabrication of GAC scaffold by an extrusion 3D bioprinting technology. The results showed that the GAC bioinks had good printability and the printed GAC scaffolds double-crosslinked by EDC/NHS and CaCl2 had rich porous structure with appropriate pore size, which were conducive to drug release and cell growth. It demonstrated that the CIP could be rapidly released by 70% in 5min, which endowed the GAC composite scaffolds with an excellent antibacterial ability. Especially, the antibacterial activities of GAC7.5 against Escherichia coli and Staphylococcus aureus within 24h were even close to 100%, and the inhibition zones were still maintained 14.78±0.40mm and 14.78±0.40mm, respectively, after 24h. Meanwhile, GAC7.5 also demonstrated impressive biocompatibility which can promote the growth and migration of L929 and accelerate wound healing. Overall, the GAC7.5 3D bioprinting scaffold could be used as a potential skin dressing for susceptible wounds with excellent antibacterial activity and good biocompatibility to meet urgent clinical needs.

2D/3D hierarchical porous structure of mNPC/SMOH@C to construct an electrochemical sensor for the simultaneous determination of p-acetylaminophenol and p-aminophenol

BackgroundAs persistent organic pollutants (POPs), the accumulation of p-acetylaminophenol (PAT) and p-aminophenol (PAP) in water can seriously damage the health of plants and animals, ultimately leading to threats to human health and safety. Electrochemical sensors have the advantages of being fast, inexpensive, and accurate compared to the complex, expensive, and cumbersome conventional analytical methods. In this study, we designed and synthesized composites with two-dimensional/three-dimensional (2D/3D) porous structures to construct an efficient electrochemical platform for the simultaneous detection of PAT and PAP. ResultsIn this work, a novel 3D foamy birnessite Na0.55Mn2O4·1.5H2O@C (SMOH@C) was synthesized, which was composited with 2D ordered mesoporous nanosheets (mNPC) to construct electrochemical sensors detecting PAT and PAP simultaneously. The prepared 2D/3D porous structure of mNPC/SMOH@C increased the exposure of active sites due to its large specific surface area. The introduction of a 3D carbon skeleton altered the charge transfer rate of SMOH@C, and the rich pore structure and oxygen-rich vacancies created favorable conditions for the diffusion and adsorption of PAP and PAT, which enabled the sensitive detection of PAT and PAP. The constructed mNPC/SMOH@C electrochemical sensor could simultaneously detect PAT (1 × 10−7 - 1 × 10−4 M) and PAP (5 × 10−8 - 1 × 10−4 M) with detection limits of 20.4 nM and 30.1 nM, respectively. The sensor has good repeatability (RSD <4 %) and reproducibility (RSD <4 %), and satisfactory recoveries (96.7–102.8 %) were obtained in the analysis of natural water samples. SignificanceIn this paper, for the first time, we present the synthesis of 3D foam birnessite and its composite with mNPC for the electrochemical simultaneous detection of PAT and PAP. Our proposed strategy for fabricating 2D/3D porous composites lays the foundation for the design and synthesis of other porous materials. In addition, this study provides new ideas for developing efficient and practical electrochemical sensors for detecting pollutants in aquatic environments.

Fabrication of Fe/KB Composite as Sulfur Host for Li-S Battery.

Lithium sulfur battery is a novel kind of secondary battery which has high energy density, however its application is greatly affected by the shuttle effect of polysulfides generated in the redox reaction of cathode electrode. Metal active sites are supposed as effective catalysts which can absorb and accelerate the conversion efficiency of lithium polysulfides, thus the shuttle effect will be alleviated. In this work, we conducted a simple way to prepare a metal Fe doped ketjen black to serve as the sulfur host of lithium sulfur battery. Ketjen black has a large specific surface area and rich porous structure, while Fe nanodot is an excellent catalyst for lithium polysulfides. Because of these advantages, the Fe/KB host can effectively confine a large amount of active material and accelerate its, therefore the Fe/KB-S cathode electrode show an excellent electrochemical performance.

A micro-meso coupled model for coral reef rocks based on CT Scanning

The coral reef rock has a rich porous structure, and establishing an entity model with a realistic porous structure will do great good to study the mechanical behavior and its mechanisms. However, the pore's characterized size of coral rocks spans four orders of magnitude from micro to meso scales (1 μm to 10 mm). This requires a large specimen size and a very small element size in the model, which leads to extremely high computational costs. To overcome this fundamental challenge, this paper uses CT to scan a macro coral specimen to obtain an entity model and establishes a micro-meso scale coupled model: (1) retaining pore’s equivalent diameter larger than 1mm in the overall CT entity, and regarding the rest part as a uniformly dense matrix material with unknown material’s properties, which is called the meso model; (2) extracting a small entity containing pore’s equivalent diameter less than 1mm from the CT entity, which is called the micro model also with unknown matrix material properties; (3) the unknown matrix material parameters in meso model are derived from mechanical response of the micro model, and the unknown matrix material parameters in micro model are confined by that meso model's mechanical responses should be coincident with that of a real coral specimen. Comparing with the uniaxial compression test result, this micro-meso coupled model has high precision and retains the influence of pores at various scales. The computational result shows that it can reduce the computational complexity of a single CT entity model by four orders of magnitude. It provides a new approach for studying similar materials' mechanical behavior and mechanisms under complex loading conditions.

Predicting and refining acid modifications of biochar based on machine learning and bibliometric analysis: Specific surface area, average pore size, and total pore volume

Acid-modified biochar is a modified biochar material with convenient preparation, high specific surface area, and rich pore structure. It has great potential for application in the heavy metal remediation, soil amendments, and carrying catalysts. Specific surface area (SSA), average pore size (APS), and total pore volume (TPV) are the key properties that determine its adsorption capacity, reactivity, and water holding capacity, and an intensive study of these properties is essential to optimize the performance of biochar. But the complex interactions among the preparation conditions obstruct finding the optimal modification strategy. This study collected dataset through bibliometric analysis and used four typical machine learning models to predict the SSA, APS, and TPV of acid-modified biochar. The results showed that the extreme gradient boosting (XGB) was optimal for the test results (SSA R2 = 0.92, APS R2 = 0.87, TPV R2 = 0.96). The model interpretation revealed that the modification conditions were the major factors affecting SSA and TPV, and the pyrolysis conditions were the major factors affecting APS. Based on the XGB model, the modification conditions of biochar were optimized, which revealed the ideal preparation conditions for producing the optimal biochar (SSA = 727.02 m2/g, APS = 5.34 nm, TPV = 0.68 cm3/g). Moreover, the biochar produced under specific conditions verified the generalization ability of the XGB model (R2 = 0.99, RMSE = 12.355). This study provides guidance for optimizing the preparation strategy of acid-modified biochar and promotes its potentiality for industrial application.

Artificial Intelligence and High-Throughput Computational Workflows Empowering the Fast Screening of Metal-Organic Frameworks for Hydrogen Storage.

Metal-organic frameworks (MOFs) are one of the most promising hydrogen-storing materials due to their rich specific surface area, adjustable topological and pore structures, and modified functional groups. In this work, we developed automatically parallel computational workflows for high-throughput screening of ∼11,600 MOFs from the CoRE database and discovered 69 top-performing MOF candidates with work capacity greater than 1.00 wt % at 298.5 K and a pressure swing between 100 and 0.1 bar, which is at least twice that of MOF-5. In particular, ZITRUP, OQFAJ01, WANHOL, and VATYIZ showed excellent hydrogen storage performance of 4.48, 3.16, 2.19, and 2.16 wt %. We specifically analyzed the relationship between pore-limiting diameter, largest cavity diameter, void fraction, open metal sites, metal elements or nonmetallic atomic elements, and deliverable capacity and found that not only geometrical and physical features of crystalline but also chemical properties of adsorbate sites determined the H2 storage capacity of MOFs at room temperature. It is highlighted that we first proposed the modified crystal graph convolutional neural networks by incorporating the obtained geometrical and physical features into the convolutional high-dimensional feature vectors of period crystal structures for predicting H2 storage performance, which can improve the prediction accuracy of the neural network from the former mean absolute error (MAE) of 0.064 wt % to the current MAE of 0.047 wt % and shorten the consuming time to about 10-4 times of high-throughput computational screening. This work opens a new avenue toward high-throughput screening of MOFs for H2 adsorption capacity, which can be extended for the screening and discovery of other functional materials.

Agarics-derived porous Fe/C material activated by ZnCl2 and its enhanced microwave absorption performance

Biomass-derived carbon materials retain the unique porous structure of biological raw materials and have environmental advantages, making them a popular choice for electromagnetic microwave absorption research. The microwave absorption performance of biomass-derived carbon materials is largely influenced by their pore structure, which can be controlled by chemical activators. In this study, ZnCl2 was chosen as the activator and de-impregnated agarics with Fe(NO3)3·9 H2O for pretreatment. The Fe(NO3)3·9 H2O can provide magnetic Fe particles for the material to enhance the magnetic loss ability. And the weakly acidic ZnCl2 can avoid the pollution of the environment, and its dehydration and dehydroxylation properties can release the hydrogen and oxygen in the biomass char material in the form of water vapor, and release the hydrogen and oxygen in the biomass carbon material in the form of water vapor, and form a porous structure. porous structure. In addition, ZnCl2 will be converted to ZnO during the activation process, and the removal of ZnO by acid washing will increase the internal pore volume, form a conductive network, and form a rich three-dimensional interconnected pore structure. The pretreated samples were vacuum carbonized at high temperature to obtain agarics-derived porous Fe/C material, which is an excellent lightweight and high-performance microwave absorbing material. The resulting material has a wider absorption bandwidth and improved microwave absorption performance. At a thickness of 2.55 mm and a frequency of 8.31 GHz, the RLmin of Fe/C material is −51.14 dB. Furthermore, at a thickness of 2.13 mm, it has an effective absorption bandwidth of 3.63 GHz, covering most of the X-band.

One-Pot construction of highly active hetero-interface over porous non-stoichiometric perovskite with gel combustion strategy to enhance toluene purification activity

Constructing active perovskite nanostructures by a simple method is of great value and significance to the practical application of non-precious metal oxide-based catalysts. Herein, a surfactant-assisted gel combustion approach was adopted to fabricate a state-of-the-art LaMnO3 perovskite catalyst with a rich porous structure and hetero-interface, which can be active for low-temperature purification of toluene. Due to the large amount of gas produced during the decomposition of surfactant, the obtained catalysts own a rich porous structure, which results in a higher specific surface area and exposes more active sites. Significantly, the highly active Mn2O3-LaMnO3 hetero-interface can be generated over the non-stoichiometric perovskite successfully through adjusting the proportion of B-site element. The introduction of hetero-interfaces alters the surface structure of the material with more oxygen vacancies, leading to a significant promoting effect. It is found that the T90 of toluene (1000 ppm in air) conversion over the sample with 30 % excess manganese (La: Mn = 1: 1.3) is only 289 °C at a relatively high weight hourly space velocity (WHSV = 120,000 mL•g−1•h−1), which is 87 °C lower than that of stoichiometric LaMnO3 perovskite. This work presents a versatile strategy for preparing highly active non-precious metal catalysts for industrial applications.

Electrodeposition of amorphous CoFe oxide/hydroxide onto nickel mesh as a highly efficient electrocatalyst for the oxygen evolution reaction

The rational design of an efficient and stable electrocatalyst is the key to driving the oxygen evolution reaction (OER) in water electrolysis. Herein, we synthesized the CoFe/Ni/NM electrode in the amorphous/crystalline phase on a nickel mesh using an electrodeposition method. The prepared CoFe/Ni/NM electrode has a rich pore structure, and the overpotentials required to generate current densities of 10 mA cm−2 and 100 mA cm−2 were 235 mV and 361 mV in 1.0 M KOH, respectively, exhibiting excellent OER-catalytic activity with stability over 72 h. To simulate industrial production, we have tested the cell Ni/NM || CoFe/Ni/NM for overall electrolysis in 6.0 M KOH, which display a current density of 879 mA cm−2 at 90 °C and 2 V.

Microorganisms immobilized hydroxyethyl cellulose/luffa composite sponge for selective adsorption and biodegradation of oils in wastewater

The highly efficient removal of oils such as oils or dyes from wastewater has aroused wide concern and is of great significance for clean production and environmental remediation. The synthesis of a novel aerogel (designated as HEC/LS) is reported herein, achieved through a sol-gel method followed by freeze-drying utilizing loofa and hydroxyethyl cellulose as the raw materials. The new HEC/LS aerogel exhibits excellent porosity and specific surface area, with a porosity of 88.70 %, a total pore area of 0.607 m2 g−1, and a specific surface area of 230 m2 g−1. The prepared HEC/LS aerogel exhibits exceptional hydrophilicity and self-floatability, facilitating its rapid absorption of water up to 21 times its own weight within a mere 3 s. Additionally, it demonstrates good adsorption performance for methylene blue (MB), with a maximum adsorption capacity of 83.30 mg g−1. Subsequently, a new hydrophobic microorganisms-loaded composite aerogel (namely, Bn-HEC/LS) was obtained by doping microorganisms into the as-prepared HEC/LS in multiple enrichment followed by a hydrophobic and oleophilic surface modification. Based on its rich porous structure and oleophilic wettability, the as-synthesized Bn-HEC/LS exhibits excellent selective adsorption and degradation properties for the oil contamination, the diesel oil could be selectively absorbed in the Bn-HEC/LS and degraded by the loaded microorganisms. Among them, B5-HEC/LS displays the highest removal efficiency of 94.50 % within 180 h, while free microorganisms and HEC/LS aerogels show degradation efficiencies of only 21.70 % and 48.10 %, respectively. The fixation of microorganisms in the aerogel increases their number within the material and enhances the relative microorganisms removal capacity. The hydrophobic and lipophilic modifications improve the selective adsorption performance of the aerogel on diesel oil, resulting in a significantly high removal rate of Bn-HEC/LS for diesel oil. The results indicate that the immobilization of microorganisms into aerogel improves the activity of microorganisms, and the hydrophobic and oleophilic modification enhances the selective adsorption performance of aerogel to diesel oil, thus resulting in a very high removal rate of Bn-HEC/LS for diesel oil. This study is expected to provide a now possibility for the green and efficient bioremediation of oils.

Microwave-absorbed porous carbon was prepared from agricultural coconut shell waste by a simple one-step high temperature charring

Coconut shell was a resourceful and renewable biomass waste in our country, which can obtain a rich pore structure after simple charring treatment. In this paper, coconut shell porous carbon (CSPC) material with good wave-absorbing properties was successfully prepared by activating coconut shell powder with KOH and charring at high temperature. The material had a porous structure, honeycomb, with the charring temperature and the proportion of activator gradually increased, the degree of graphitization gradually increased. When the charring temperature was 600 ℃ and the activator ratio was 0.5:1, the minimum reflection loss (RL min) value was −37.23 dB when the sample thickness was 1.5 mm and the test frequency was 16.72 GHz. The coconut shell porous carbon prepared was a new type of electromagnetic wave-absorbing material made from agricultural waste, which can obtain a better microwave absorption effect after simple processing.

Green synthesis of a superhydrophobic porous organic polymer for the removal of volatile organic compounds at high humidity

Superhydrophobic porous organic polymers are potential sorbents for volatile organic compounds (VOCs) pollution control by suppressing the competition of water molecules on their surfaces. However, the synthesis of superhydrophobic reagents usually requires large amounts of organic solvents and a long reaction time (≥ 24 h). Herein, a green mechanochemical method was developed to synthesize a superhydrophobic polymer (MSHMP-1) with the advantages of using a small amount of organic solvents (5 mL/g) and a short reaction time (2 h). Meanwhile, MSHMP-1 with a water contact angle (WCA) of 162° exhibited a dramatically rich pore structure as revealed by its specific surface area (SSA) of 1780 m2/g. The decrease in the adsorption of benzene on MSHMP-1 due to the competition of water molecules, even at relative humidity of 90 %, was nonsignificant (<10 %), indicating the great application potential of MSHMP-1 in hydrophobic adsorption. Moreover, the adsorption capacity of MSHMP-1 was maintained after at least five adsorption–desorption cycles. Therefore, MSHMP-1 can be a remarkable adsorbent for the removal of hazardous VOCs, especially at high humidity levels.

Long-Term performance of composite Cu-Fe ore oxygen carrier by Extrusion-Spheronization in chemical looping combustion

High-performance and low-cost oxygen carrier is vital for engineering demonstration and industrial application of chemical looping combustion. In this work, binary-ore (copper ore and iron ore) oxygen carriers are prepared at a large scale (25 kg/h) by the extrusion-spheronization method, using montmorillonite as the inert support. The anti-sintering ability and long-term stability are systematically investigated through well-organized tests in a thermogravimetric analyzer (TGA) and batch fluidized bed reactor (BFB). Four kinds of low-cost composite oxygen carriers are prepared with montmorillonite content of 10 wt%∼40 wt%, and the montmorillonite loading ratio is optimized as 10 wt% through 100-cycle TGA tests, with the fastest reduction rate of 0.155 %/s. The results show that the CO2 yield is always beyond 90 %, suggesting the stable reactivity of FeCu-10 M, and the average attrition rate is 0.108 %/h. No significant sintering or agglomeration is detected in the inner surface or among the particles, as indicated by SEM images. The specific surface area is developed from 0.125 to 0.185 m2/g, and the rich pore structure remains in the 100-cycle test. Additionally, the crushing strength of FeCu-10 M is higher than 2 N throughout the cyclic experiment, and the lifetime is 2 ∼ 7 times longer than that of the original iron ore. The extrusion-spheronization method has the potential in the industrial-scale preparation of oxygen carriers, and the FeCu-10 M is a favorable oxygen carrier to the chemical looping combustion process.

Advanced Applications of Porous Materials in Triboelectric Nanogenerator Self-Powered Sensors.

Porous materials possess advantages such as rich pore structures, a large surface area, low relative density, high specific strength, and good breathability. They have broad prospects in the development of a high-performance Triboelectric Nanogenerator (TENG) and self-powered sensing fields. This paper elaborates on the structural forms and construction methods of porous materials in existing TENG, including aerogels, foam sponges, electrospinning, 3D printing, and fabric structures. The research progress of porous materials in improving TENG performance is systematically summarized, with a focus on discussing design strategies of porous structures to enhance the TENG mechanical performance, frictional electrical performance, and environmental tolerance. The current applications of porous-material-based TENG in self-powered sensing such as pressure sensing, health monitoring, and human-machine interactions are introduced, and future development directions and challenges are discussed.

Low-cost and green straw derived hierarchical porous carbon as support to phosphotungstic acid for efficient and clean production of α-terpineol

This study developed a novel reciprocal template method to prepare MgO@Carbon micrometre tubes directly from straw-based biomass. Biomass carbon with a rich hierarchical porous structure (MRSC30) was obtained by acid-washing the MgO@Carbon micrometre tubes. The pore formation mechanism of MRSC30 was systematically analyzed using Density Functional Theory calculations and various characterization methods. The in situ growth of Mg(OH)Cl/MgO inside the biomass promotes the polymerized carbon precursors to be tightly affixed to the templating agent and provides exfoliation, support, and catalysis (i.e., electrostatic attraction, nucleophilic substitution, and electrophilic addition), which effectively promotes the formation of hierarchical porous carbon. The continuous release of light gases from the inside out during the prolongation of the decomposition temperature of the biomass by Mg(OH)Cl or/and MgO helps to promote the formation of stomata in the biomass carbon. The results showed that the method minimized the consumption of chemicals, energy consumption, and the time required to prepare HPC by 35.75%, 67.57%, and 52.38%, respectively. The phosphotungstic acid-loaded MRSC30 was successfully prepared as a highly amphiphilic and highly acidic solid acid catalyst and applied to the hydration of α-pinene to prepare superior performance gasoline additives (α-terpineol). Under optimal process conditions obtained in a batch reactor, the catalytic performance of the catalyst could be further improved by alternating flow using a novel semi-batch unsteady-state reactor developed in this institute, and the α-pinene conversion and the α-terpineol selectivity reached a maximum of 95.53% and 65.75%, respectively. At the same time, the reactor was able to substantially reduce the time required for hydration and the amount of moderately toxic acetone used compared to the conventional batch reactor by 20.83% and 62.50%, respectively.

Synergistic effects of Co-pyrolysis on the immobilization and transformation of lead (Pb), chromium (Cr), nickel (Ni), and fluorine (F) in phosphogypsum-biomass mixtures

Co-pyrolysis of biomass with phosphogypsum (PG) presents an effective strategy for facilitating the recycling of PG resources. However, it is crucial to note the environmental threats arising from the presence of Pb, Cr, Ni, and F in PG. This study investigated the effect of immobilization and transformation of four elements during co-pyrolysis with biomass and its components. The co-pyrolysis experiments were carried out in a tube furnace with a mixture of PG and corn stover (CS), cellulose (C), lignin (L), glucose (G). Co-pyrolysis occurred at varying temperatures (600 °C, 700 °C, 800 °C, and 900 °C) and different addition ratios (10%, 15%, and 20%). The results indicated that an increase in co-pyrolysis temperature was more conducive to the immobilization and transformation of harmful elements in PG, demonstrating significant efficacy in controlling F. Additionally, the addition of biomass components exerts a significant impact on inhibiting product toxicity, with small molecules such as glucose playing a prominent role in this process. The mechanism underlying the control of harmful elements during co-pyrolysis of PG and biomass was characterized by three main aspects. Firstly, biomass components have the potential to melt-encapsulate the harmful elements in PG, leading to precipitation. Secondly, the pyrolysis gas produced during the co-pyrolysis process contributes to the formation of a rich pore structure in the product. Finally, this process aids in transforming hazardous substances into less harmful forms and stabilizing these elements. The findings of this study are instrumental in optimizing the biomass and PG blend to mitigate the environmental impact of their co-pyrolysis products.