CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Penggang Li,Ping Zhang,Aishu Li,Lin Yu,Mengying Si,Qi Liao,Zhihui Yang,Weichun Yang
Understanding the formation of uranyl-arsenate compounds (M(UO 2 ) 2 (AsO 4 ) 2 ·nH 2 O, M represents divalent metallic cations) is of great importance in controlling the mobility and fate of uranium (U) and arsenic (As) in the natural environment. Phosphate is a ubiquitous coexisting ion with properties similar to arsenate and can complex with uranyl to form uranyl phosphate compounds, thus potentially affecting the formation of uranyl-arsenate compounds. Herein, the effect of phosphate, on the immobilization of uranyl, arsenate and divalent metallic cations (e.g., Fe 2+ , Mg 2+ , Ni 2+ , Cu 2+ ) was explored. Surprisingly, the presence of phosphate promoted the immobilization of uranyl arsenate with the divalent metallic cations under acidic conditions. For example, at pH 3.0, the immobilization efficiency of uranyl and arsenate in the uranyl-arsenate-Fe 2+ system increased from 20.6 % and 18.6 % to 82.6 % and 52.2 %, respectively. Moreover, the chemical stability of the formed uranyl arsenate-bearing compounds in the presence of phosphate is significantly improved, and the TCLP leachability of As and U decreased by 81 % and 97 %, respectively. The experimental results illustrated that with PO 4 3- served as a proton acceptor, uranyl and arsenate species were changed and more metallic cations participate in immobilization. Gibbs free energy and Gibbs free energies change also illustrated that the formation of Fe(UO 2 ) 2 (AsO 4 ) 2 ·5H 2 O was relatively thermodynamically favorable in the presence of phosphate. The results of thermodynamic calculations could account for the enhancement effects of phosphate on immobilization of uranyl arsenate. The findings have important implications for the mobility and fate of U and As and the solution of their co-contamination, especially in acidic environments.
研究领域:
环境科学
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化学
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DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2024
·
IF 5.8
Zixu Chen,Peigang He,Wanlin Li,Shengjian Zhao,Dechang Jia,Paolo Colombo,Yu Zhou
Geopolymers with zeolite-like structures can effectively immobilize radioactive ions through their three-dimensional cage-like framework. This study investigated the synthesis of geopolymers via cold reaction sintering using metakaolin, anhydrous and nonahydrate sodium metasilicate for Cs + immobilization. Optimizing the Si/Al molar ratio to 1.5:1 and water content to 20 wt% yielded the best mechanical properties and near-complete reaction. The transient liquid phase formed by the dehydration of sodium metasilicate nonahydrate facilitated densification. CsCl incorporation resulted in a predominantly amorphous phase with the formation of NaCl crystals. Toxicity leaching tests demonstrated Cs + immobilization rate exceeding 91 % for CsCl content below 12 wt%. Short-term leaching tests confirmed low leaching rates (< 4 × 10⁻³ cm/day after 4 days), and leachability indices well above the typically required value of 6 for cement-based matrices. These results establish the viability of cold reaction sintered geopolymers for Cs + immobilization, highlighting their promise for nuclear waste management applications.
研究领域:
材料科学
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核废物管理
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DOI
高影响因子
CATALYSIS LETTERS
·
2024
·
IF 2.3
Shen Nan,Hua Shaofeng
A dual-enzyme cascade catalytic system (Cu-rGO-Fe 3 O 4 -GA-CEL-PEI-GOD) was prepared by co-immobilizing cellulase (CEL) and glucose oxidase (GOD) on a nanocomposite (Cu-rGO-Fe 3 O 4 ) to efficiently catalyze the conversion of carboxymethyl cellulose (CMC) to gluconic acid. A layer-by-layer strategy was used by adding polyethyleneimine (PEI) to allow the upper enzyme layer to attach to the lower neighboring layer, increasing the loading capacity of the support. The loading capability of CEL and GOD on Cu-rGO-Fe 3 O 4 -GA-CEL-PEI-GOD were 55.034 mg g −1 and 12.4 mg g −1 , respectively. The specific activity of CEL on Cu-rGO-Fe 3 O 4 -GA-CEL was 74.3 U·g −1 , and that of immobilized CEL after cross-linking PEI was 25.45 U·g −1 , which could retain 34.253% of the enzyme activity. The specific activity of GOD on Cu-rGO-Fe 3 O 4 -GA-CEL-PEI-GOD was 30.9 U·g −1 . The carrier Cu-rGO-Fe 3 O 4 has peroxidase-like activity, which can timely remove harmful H 2 O 2 to the enzyme, thereby improving the yield of gluconic acid and the stability of biocatalysts. The yield of gluconic acid with Cu-rGO-Fe 3 O 4 -GA-CEL-PEI-GOD reached 96.04% within 2 h, higher than the control systems for comparison. In addition, the Cu-rGO-Fe 3 O 4 -GA-CEL-PEI-GOD maintained 82.61% of catalytic activity even after undergoing seven cycles of reaction. The dual-enzyme catalytic systems had shallow temperature and pH optima of 40 °C and 4.5. Such a chemoenzymatic cascade system provides a new strategy for the conversion from CMC to gluconic acid in one-step. Graphical Abstract Enzymatic conversion of sodium carboxymethyl cellulose (CMC-Na) to gluconic acid.
研究领域:
生物催化
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纳米技术
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酶工程
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材料科学
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产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2025
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IF 6.7
Qian Zuo,Bing Li,Zhiyi Deng,Xiangyu Zheng,Ping Li,Jinhua Wu
Zero-valent iron (Fe 0 ) is widely packed in filters for Cr(VI) removal, but it suffers from ferrochrome precipitate passivation. In this study, a mixed Fe 0 and biochar (BC) system was established and investigated for promoted Fe 0 corrosion and enhanced Cr(VI) removal through iron‑carbon micro-electrolysis (IC-ME) by batch and column experiments with Fe 0 and BC as controls. Due to electrochemical reaction between Fe 0 and BC, there was an enhancement in iron corrosion and subsequent formation of secondary minerals on Fe 0 surface. These minerals included magnetite, lepidocrocite, and goethite, which facilitated Cr(VI) adsorption and reduction. The Fe 0 -BC system therefore obtained a higher Cr(VI) removal rate of 86.3 % within 6 h than those of the BC (7.9 %) and Fe 0 (12.5 %) systems. Chromium species distribution showed that 76.2 % of removed Cr(VI) was converted to Cr(III). The resultant Cr(III) of 68.4 % was immobilized on Fe 0 and BC surfaces due to precipitation and sequestration. The optimal Fe/BC mass ratio was 2:1 for galvanic reaction and Cr(VI) removal. The removal of Cr(VI) by Fe 0 -BC exhibited a pH-dependency, with acidic conditions favoring higher removal rates. Additionally, the column experiment result revealed that Cr(VI) removal capacity of 4.0 mg Cr(VI)/(g Fe 0 ) and operational lifespan of 1851 PV in the Fe 0 -BC column were 6.7 and 3.9-fold greater than those in the Fe 0 column, further confirming that galvanic reaction could effectively alleviate Fe 0 surface passivation. These results indicated that mixed Fe 0 and BC as an effective medium in filter tanks could form IC-ME to enhance Cr(VI) reduction and immobilization during water treatment.
研究领域:
环境科学
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水处理工程
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2024
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IF 5.1
Sihao Wang,Chaonan An,Yining Zhang,Xu Wang,Xuepeng Wang,Jing Pan,Fuqiu Ma,Yun Xue,Yongde Yan
Zinc Titanate (ZIT) glass-ceramic composite is a potential candidate waste form for immobilizing radioactive lanthanide oxides due to its relatively high lanthanide embedding capacity and low reaction temperature. However, the composition of lanthanide oxides after electrolytic refining is very complex and the immobilization mechanism of lanthanide oxides by ZIT composite is not clear. Herein, we prepared ZIT-PrEu glass-ceramic waste forms by a solid-phase sintering method at 1200 °C for 4 h using mixed lanthanide oxides of Pr 6 O 11 and Eu 2 O 3 simulated as radioactive waste. The XRD and SEM results show that different mixed lanthanide oxide ratios have very little effect on the composition and microstructure of ZIT-PrEu waste forms with different waste embedding rates. With the increase of waste embedding rate, the density of the ZIT-PrEu glass-ceramic waste forms with different mixed lanthanide oxide ratios first increases and then decreases. When the embedding rate increases to 25 wt%, the density of ZIT-PrEu waste forms with different mixed lanthanide oxide ratios reaches a maximum. The ZIT-PrEu glass-ceramic waste forms embedded with 25 wt% waste exhibit excellent chemical durability, and the leaching rates of Pr ion and Eu ion are only 10 −6 - 10 −7 g m −2 d −1 after 28 days at 90 °C. Moreover, the phase evolution of the ZIT composites immobilizing lanthanide oxides at different temperatures is revealed by XRD and FT-IR measurements. The lanthanides (Ln) are mainly present in the form of LnPO 4 monazite phases.
研究领域:
材料科学
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核废料管理
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2025
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IF 11.3
Yonghui Xing,Wenjing He,Changshui Cai,Song Liu,Yi Jiang,Shuxin Tan,Chenchen Qu,Xiuli Hao,Peng Cai,Qiaoyun Huang,Wenli Chen
Soil mineral properties significantly influence the mobility of Cd(II) within the soil matrix. However, the limited understanding of how microbial metabolism affects mineral structure at the microscale poses challenges for in situ remediation. Here, we designed a model calcium-phosphate system in a urea-rich environment to explore the impact of different microbial activation levels on Cd(II) fixation at mineral interfaces. Findings indicate that bacteria affected the morphological structure of the minerals and the amount of carbonate incorporation (average 5.4 %), thereby enhancing Cd(II) immobilization capacity (up to 9.6 times). This process is influenced by the intensity of bacterial activation, as reflected in their urease activity. Extracellular substances secreted by bacteria are also essential for activating minerals, contributing to a sustained decrease in their surface potential. The introduction of activated minerals in potting experiments markedly stimulated the soil urease activity, promoting the enrichment of functional bacteria and facilitating Cd(II) passivation, thereby reducing Cd(II) uptake by vegetables. An extensive soil survey further corroborated a linkage between soil total phosphorus and urease activity, indirectly emphasizing the universality of phosphate mineral-urease microbial interactions and their critical role in the morphological transformation of Cd(II). Our findings highlight the functional dynamics of urease microorganisms in shaping soil mineral landscapes and regulating heavy metal mobility, with broad implications for soil microscale remediation strategies.
研究领域:
环境科学
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微生物学
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土壤学
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DOI
PubMed
高影响因子
ACS Applied Nano Materials
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2024
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IF 5.3
Zeqing Liu,Yuhan Li,Lingmei Dai,Dehua Liu,Wei Du
Single-crystalline ordered macro-microporous CuBTC shows excellent mass transfer performance and has high fatty acid stability, making it highly promising as an enzyme immobilization carrier. However, its practical application is severely limited by its poor water stability. To address this challenge, we introduced a ligand, 1,2,3-benzotriazole (BTA), known for its hydrophobicity and strong coordination with copper. A series of CuBTC-derived dual-ligand SOM-MOFs (SOM-MIXs) was successfully synthesized with enhanced hydrophobicity and improved water stability. The CuBTC-derived SOM-MIXs demonstrated superior performance for lipase immobilization, resulting in a maximum increase of 66.9% in specific activity. To address the limitation that excessive addition of 1,2,3-benzotriazole does not further enhance the hydrophobicity of the carrier and may lead to structural damage, a sol–gel method was employed to coat the SOM-MIX with highly hydrophobic PDMS, leading to a further increase of 139.1% in the specific activity. The resulting immobilized lipase exhibited excellent catalytic performance and remarkable reusability, with 90.09% activity retention after five cycles in the synthesis process of 1-oleoyl-2-palmitoyl-3-linoleoylglycerol (OPL) by acidolysis. This work highlights the potential of SOM-MIX@PDMS and provides valuable insights into the rational design and postmodification of metal–organic frameworks (MOFs) for enzyme immobilization in diverse applications.
研究领域:
生物化学
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材料科学
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酶工程
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DOI
高影响因子
Materials
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2024
·Vol. 17
·期 6
·1431
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IF 3.1
Bao Mi,Hui Zhao,Meng Lu,Yi Zhou,Yongjie Xue
The massive stockpiling of electrolytic manganese residue (EMR) has caused serious environmental pollution. In this study, EMR, coal gangue (CG), and fly ash (FA) were used as raw materials to obtain the optimal mix ratio based on Design-Expert mixture design. The effects of activator modulus, liquid–solid (L/S) ratio, and curing temperature on the mechanical properties of geopolymers were investigated. The results showed that the compressive strength of the prepared geopolymer was 12.0 MPa, and the 28d leaching of Mn was 0.123 mg/L under the conditions of EMR:CG:FA = 0.43:0.34:0.23, L/S = 0.9, a curing temperature of 60 °C, and a curing time of 24 h. This indicates that the geopolymer is an environmentally friendly material with high compressive strength. The mineral composition of the geopolymer is mainly hydrated calcium silicate and geopolymer gel. In addition, a more stable new mineral phase, MnSiO3, was generated. The Fourier transform infrared (FTIR) spectrogram showed that the peak at 1100 m−1was shifted to 1112 cm−1, which indicated that a geopolymerization reaction had occurred. Through scanning electron microscopy (SEM) and energy dispersive spectrum (EDS) analysis, it was identified that the geopolymerization produced a large amount of amorphous gelatinous substances with a relatively dense structure, the major elements being oxygen, silicon, aluminum, calcium, and sodium.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2024
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IF 3.8
Yuxiang Zhang,Yao Zhang,Luyao Zhang,Yongdong Liu
The use of nanobodies (Nbs) in affinity chromatography for biomacromolecule purification is gaining popularity. However, high-performance Nb-based affinity resins are not readily available, mainly due to the lack of suitable immobilization methods. In this study, we explored an autocatalytic coupling strategy based on the SpyCatcher/SpyTag chemistry to achieve oriented immobilization of Nb ligands. To facilitate this approach, a variant cSpyCatcher003 (cSC003) was coupled onto agarose microspheres, providing a specific attachment site for SpyTagged nanobody ligands. The cSC003 easily purified from Escherichia coli through a two-step procedure, exhibits exceptional alkali resistance and structural recovery capability, highlighting its robustness as a linker in the coupling strategy. To validate the effectiveness of cSC003-derivatized support, we employed VHSA, a nanobody against human serum albumin (HSA), as the model ligand. Notably, the immobilization of SpyTagged VHSA onto the cSC003-derivatized support was achieved with a coupling efficiency of 90 %, significantly higher than that of traditional thiol-based coupling method. This improvement directly correlated to the preservation of the native conformation of nanobodies during the coupling process. In addition, the Spy-immobilized resin demonstrated better performance in the binding capacity, with a 3-fold improvement in capture efficiency, underscoring the advantages of the Spy immobilization strategy for oriented immobilization of VHSA ligands. Moreover, online purification and immobilization of SpyTagged VHSA from crude bacterial lysate was achieved using the cSC003-derivatized support. The resulting resin exhibited high binding specificity towards HSA, yielding a purity above 95 % directly from human serum, and maintained good stability throughout multiple purification cycles. These findings highlight the potential of the Spy immobilization strategy for developing Nb-based affinity chromatographic materials, with significant implications for biopharmaceutical downstream processes.
研究领域:
生物化学
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分子生物学
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生物工程
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DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2025
·
IF 6.2
Frank Peprah Addai,Xinglin Chen,Hao Zhu,Zongjian Zhen,Feng Lin,Chengxiang Feng,Juan Han,Zhirong Wang,Yun Wang,Yang Zhou
Glucoamylases (GLL) hydrolyze starch to glucose syrup without yielding intermediate oligosaccharides, but their lack of stability under industrial conditions poses a major limiting factor. Using consensus- and ancestral-based machine-learning tools, a functional GLL with six mutations (GLLI73l/T130V/N212V/D238G/N327M/S332P) was constructed that exhibited superior hydrolytic activity relative to the wild-type (WT-GLL). An oxidized multi-walled carbon nanotube (oMW-CNT) was used as a solid support to immobilize the WT-GLL with an immobilization capacity of 211.28 mg/g. The specific activity of mutant GLL-6M and GLL@oMW-CNTII was improved by 2.5-fold and 3.9-fold respectively, with both retaining 64.5% residual activity after incubation at 50 °C for 2 h compared to the WT-GLL with 42.6% activity. GLL and GLL-6M were however completely inactivated at 55 °C in 30 min while oMW-CNTII retained ∼43.1% activity. Our results demonstrate that employing a machine-learning approach for enzyme redesign and immobilization is a practicable alternative for improving enzyme performance and stability for industrial applications.
研究领域:
生物化学
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酶工程
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工业生物技术
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DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
·
IF 5.4
Fang Miao,Lun Xiong,Mingquan Jiang,Guolin Yang,Hui Zhu,Jiehong Lei
Improper treatment of radioactive iodine vapor generated during spent fuel reprocessing can lead to significant environmental hazards. This study aims to synthesize a choline hydroxide-functionalized silica aerogel composite material (CH-Si aerogel) to enhance iodine capture through hydroxyl-induced polarization of iodine molecules. The polarized iodine subsequently forms polyiodide anions, which are effectively captured via electrostatic interactions with the positively charged quaternary ammonium nitrogen centers. The results indicate that CH-Si aerogel achieves an iodine adsorption capacity of up to 1362.43 mg/g, significantly surpassing previously reported silica-based adsorbents. DFT calculations reveal that hydroxyl groups substantially enhance the polarization of iodine molecules, leading to changes in the electron density at the adsorption sites. Furthermore, the quaternary ammonium nitrogen centers interact with polyiodide anions through electrostatic adsorption, reinforcing the material’s iodine capture capability. The material exhibits adsorption energies of –1.855 eV for I 2 and –3.875 eV for polarized iodine ions, demonstrating robust stability and excellent adsorption performance. In addition, CH‑Si aerogel maintains excellent iodine capture capacity even under complex conditions of high humidity (RH=50 %) and highly humid acidic environments (pH=1). CH-Si aerogel exhibits excellent potential for practical applications, offering new insights for the development of efficient iodine capture materials.
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高影响因子
Foods
·
2025
·Vol. 14
·期 11
·1981
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IF 5.1
Dexin Zhao,Shiguo Peng,Feifei Chen,Alei Zhang,Kequan Chen
In this study, we developed an innovative method for one-step enzyme purification and immobilization utilizing polysaccharide-based microspheres through a chitosan-binding module that mediated affinity adsorption. The chitosan-binding domain derived fromPaenibacillussp. IK-5 was genetically fused with multiple target enzymes (lysine decarboxylase, glutamate oxidase, and formate dehydrogenase), all of which were successfully expressed in soluble forms. Three distinct polysaccharide microspheres with optimized surface characteristics were engineered to facilitate the concurrent purification and immobilization of these fusion enzymes. Comprehensive characterization using organic elemental analysis, fluorescence microscopy, and thermogravimetric analysis confirmed the efficient immobilization of fusion enzymes. Remarkably, the immobilized enzymes demonstrated exceptional operational stability, maintaining over 80% of their initial catalytic activity after ten consecutive reuse cycles. This study establishes a robust and versatile platform for enzyme immobilization, providing significant advantages in biocatalyst engineering applications.
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）