PROGRESS IN ORGANIC COATINGS
·
2014
·
IF 2.302
Feigao Xu,Ning Xiang,Dan Li,Jiangang Yu,Daishe Wu,Qingjian Zhang
Deterioration of monuments constructed of limestone could be potentially arrested by applying a combination of coupling agents with consolidants, which can prevent acid attack and mechanical weakening. Two different coupling agents including N-(2-aminoethyl)-3-aminopropyl methyl dimethoxysilane (AE-APMDMS) and diethyl phosphatoethyl triethoxysilane(DEPETES) were used to link calcite . Calcite was impregnated with these coupling agents and studied by FTIR, TG-DSC and contact angle measurement. According to these techniques, new bands, a two stage decomposition pattern appeared and a slight increase in surface hydrophobicity for AE-APMDMS and DEPETES that indicated interactions between the coupling agents and calcite . The Scotch Tape test and compressive strength test showed that the cohesion between consolidant and limestone powder improved, while the ability of consolidation decreased, which were resulted by coupling agents. Resist acid test on limestone powder coated with the coupling agents resulted in a decreased deterioration rate. Limestone treated with combined consolidant plus AE-APMDMS or DEPETES showed a significant decrease in capillarity water absorption.
研究领域:
材料科学
·
文物保护
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2017
·
IF 5.715
Lingjun Kong,Minhua Su,Yan Peng,Li'an Hou,Juan Liu,Haipeng Li,Zenghui Diao,Kaimin Shih,Ya Xiong,Diyun Chen
Because of the widespread application of activated carbon (AC) as adsorbents, reduced production costs are highly desirable, therefore, inexpensive alternatives for activated carbon precursors and eco-procedures are presently sought. In this work, AC was successfully prepared from sawdust through co-calcinations with limestone. The surface area and porosity of the resulting ACs were evaluated according to the N 2 adsorption at 77 K. Acid Orange II (AOII) was utilized as a negative dye to study the potential of the resulting AC as an adsorbent. Results revealed that the surface area and total pore volume were both increased greatly. When the activated carbon was prepared in mass ratios of 1:2 and 1:1 (calcium carbonate to sawdust), the surface area increased to 611.4 and 706.9 m 2 /g, respectively, and the adsorption capacities increased to 310.89 and 389 mg/g. These enhancements indicated efficient activation, resulting in energy-saving and environmentally friendly activated carbon production. Thus, this paper provides a cleaner process for producing activated carbon from waste sawdust through bioresource recycling.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Zhendong Liu,Longguan Zhu,Bingjian Zhang
Due to natural erosion and human interference, limestone artifacts often suffer from cracks and gradual detachment. There is a critical need for new bonding materials that possess excellent aging resistance and high compatibility with the artifact substrates. This study investigates the effects of varying proportions of citric acid (CA) and borax (B) as composite retarders on the fundamental properties of magnesium phosphate cement (MPC). Through the application of X-ray diffraction techniques and cold field emission scanning electron microscopy, this research elucidates the mechanisms by which the retarders affect MPC. It was found that a 5 % addition of CA and B significantly reduces the hydration temperature during the early stages of MPC setting, enhances the unconfined compressive strength (reaching 44.3 MPa at 28 days), and allows for controllable setting times (17 minutes). Additionally, the presence of CA was found to delay crystal growth, resulting in an increased quantity of the amorphous phase and higher density of MPC. The optimal MPC formulation was selected as a bonding and repair material for limestone artifacts. For comparative analysis, traditional glutinous rice lime mortar (GL) and commercially available epoxy resin (EP) were tested under wet-dry cycling and UV aging conditions. Results indicated that EP materials demonstrated significant aesthetic incompatibilities and progressive cracking and detachment as aging tests progressed. GL materials exhibited significantly lower bonding strength compared to EP and MPC. In contrast, MPC displayed excellent aging resistance, moderate bonding strength, and a Shore hardness value closely matching that of the limestone substrates. Therefore, high-strength, rapid-hardening MPC represents a valuable and forward-looking solution for the conservation of limestone artifacts.
研究领域:
材料科学
·
文物保护
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2023
·
IF 5.8
Qixian Xie,Lili Wan,Zhuang Zhang,Jingshan Luo
The cement industry is one of the largest contributors to global CO 2 emissions, which has been paid more attention to the research on converting the CO 2 released by the cement production process. It is extremely challenging to decarbonize the cement industry, as most CO 2 emissions result from the calcination of limestone (CaCO 3 ) into CaO and CO 2 . In this work, we demonstrate an in situ electrochemical process that transforms CaCO 3 into portlandite (Ca(OH) 2 , a key Portland cement precursor) and valuable carbonaceous products, which integrates electrochemical water splitting and CO 2 reduction reaction with the chemical decomposition of CaCO 3 . With different metal catalyst electrodes (like Au, Ag, In, Cu, and Cu nanowires electrodes), we have achieved various valuable carbonaceous products, such as CO, formate, methane, ethylene, and ethane during the electrochemical CO 2 process. Our work demonstrates a proof of concept for green and sustainable cement production.
研究领域:
材料科学
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环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2021
·Vol. 29
·期 6
·1727-1741
·
IF 3.667
Peng Xilong,Li Yue,Liu Shuang,Jiang Tian,Chen Wenjin,Li Dan,Yuan Jiren,Xu Feigao
In this experiment, chitosan (CS), waste limestone and diammonium hydrogen phosphate were used as raw materials to synthesize HAp-coated-stone composites/CS by one-step blending method. Then, the prepared HAp-coated-stone composites/CS composite material was used to remove Cu (II) in the solution. The structure and microstructure of the composite were characterized by Fourier transform infrared spectroscopy, X-ray diffraction analysis, Scanning Electron Microscopy, Brunauer–Emmett–Teller and Thermogravimetric Analysis. The results showed that with the addition of CS, the overall thermal stability of the composite improved, while its specific surface area decreased. Moreover, the composite was a mesoporous material. HAp-coated-stone/CS composites with small amounts of CS (0.5%) can remarkably increase Cu (II) removal. The HAp-coated-limestone/CS-0.5% had better resistance to pH changes compared with HAp-coated-limestone. Under the initial concentration of 20 mg/L, the maximum adsorption capacity for Cu (II) adsorption by HAp-coated-limestone/CS-0.5% was about 130.75 mg/g at 40 °C. The equilibrium data and kinetic were well described by Freundlich models and pseudo-second-order, respectively. The possible mechanisms for Cu (II) adsorption onto HAp-coated-stone/CS composites surface have been proposed.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Zhendong Liu,Longguan Zhu,Yulan Hu,Bingjian Zhang
The limestone cultural relics within the West Lake World Cultural Heritage Site in Hangzhou, China, have suffered severe material loss and deep cracks due to prolonged natural and anthropogenic erosion. This necessitates the urgent development of highly efficient and compatible stone-mimicking restoration materials for their repair and preservation. This study systematically investigates the effects of varying metakaolin (MK) additions on the performance and microstructure of magnesium phosphate cement (MPC). Using mercury intrusion porosimetry, X-ray diffraction (XRD), thermogravimetric-differential scanning calorimetry (TG-DSC), and scanning electron microscopy (SEM), it was found that MK significantly enhances the mechanical properties of MPC by filling pores and forming aluminum phosphate gel, while also prolonging the setting time of the paste. Based on these findings, MPC with 30 % MK addition (F-MPC) was selected as the binder, and commonly used materials in cultural heritage restoration—hydraulic lime (F-NHL), Portland cement (F-OPC), and epoxy resin (F-EP)—were employed as comparative materials. Calcite particles and iron oxide pigments were incorporated to create stone-mimicking restoration materials. Results showed that the mechanical strength of F-NHL and F-OPC was significantly lower than that of the limestone substrate, whereas F-EP exhibited much higher strength but severely compromised the substrate's breathability. In contrast, F-MPC demonstrated excellent compatibility with limestone in terms of mechanical properties while maintaining good breathability. This study provides theoretical support and practical guidance for the innovative application of magnesium phosphate in limestone restoration, highlighting its significant value and broad prospects in the field of cultural heritage conservation.
研究领域:
文物保护
·
建筑材料科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2019
·
IF 5.714
Zhen Zhang,Shuran He,Yulong Zhang,Kun Zhang,Jinjin Wang,Ran Jing,Xingjian Yang,Zheng Hu,Xiaojing Lin,Yongtao Li
In the present study, the competitive adsorption of Cu 2+ , Pb 2+ , and Cd 2+ by a novel natural adsorbent (i.e., argillaceous limestone) modified with chitosan (C-AL) was investigated. The results demonstrated that both intraparticle diffusion and chemisorption marked significant contributions to the Cu 2+ adsorption process by both raw argillaceous limestone (R-AL) and C-AL in mono-metal adsorption systems. Antagonism was found to be the predominant competitive effect for Cu 2+ , Pb 2+ and Cd 2+ adsorptions by C-AL in the multi-metal adsorption system. The three-dimensional simulation and FTIR analysis revealed that the presence of Cu 2+ suppressed Pb 2+ and Cd 2+ adsorptions, while the effect of Cd 2+ on Cu 2+ and Pb 2+ adsorptions was insignificant. The spectroscopic analyses evidenced that amide groups in C-AL played a crucial role in metal adsorption. The preferential adsorptions of Pb 2+ > Cu 2+ > Cd 2+ were likely due to the different affinities of the metals to the lone pair of electrons on the N atom from the amide groups and/or the O atoms from the –OH and -COO - groups on C-AL. The interactions between C-AL and metal ions and between various metal species influenced their competitive adsorption behaviors. C-AL exhibited a superior metal adsorption capacity in comparison with that the capacities of other natural adsorbents reported during the last decade, suggesting its potential practical applications.
研究领域:
环境科学
·
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2021
·
IF 3.605
Wenbo Jia,Chuanmin Chen,Songtao Liu,Yue Cao
In this study, the Hg0 removal characteristics of NaClO2 in limestone slurry were investigated in a bubbling reactor. The effects of slurry conditions (pH, temperature, and Cl– concentration) and flue gas components (NO, SO2, HCl, etc.) on Hg0 removal activity and efficient Hg0 removal duration were explored. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to characterize the solid products prepared under different conditions. It was found that NaClO2 exhibited superior Hg0 removal activity when both SO2 and NO were present in the flue gas, while the Hg0 removal efficiency reduced significantly in the absence of SO2 and/or NO. The Hg0 removal activity of NaClO2 decreased significantly with the increase of pH value. The slurry temperature had no obvious effect on Hg0 removal activity, while higher temperature could enhance the Hg0 re-emission at a later stage. However, the presence of Cl– in limestone slurry could notably inhibit the Hg0 re-emission. The characterization results showed that the presence of SO2 and NO promoted the formation of HgCl2, Hg(NO3)2, and HgSO4, thus significantly enhancing the Hg0 removal activity of NaClO2 in limestone slurry.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zhen Huang,Ziyang Chu,Haibo Liu,Tianhu Chen,Xuehua Zou,Fuwei Sun,Dong Chen
Effective removal of heavy metal complexes from contaminated water remains a challenging task. In this work, a limestone/PMS system was constructed for the efficient degradation of Cu-EDTA. Under the conditions of 3.0 g/L limestone and 1.0 mM PMS, the degradation efficiency of 10.0 mg/L Cu-EDTA reached 99.0 % in 60 min, and the removal efficiency of Cu ions approached 50.0 %. The main active specie revealed by quenching and EPR experiments was the singlet oxygen ( 1 O 2 ). Interestingly, Trace amounts of Cu(II) in limestone react with PMS enhancing the degradation of Cu-EDTA. The results of the HPLC-MS analysis showed that the reactive species attacked the Cu–O and Cu–N bonds, as well as triggered a decarboxylation process, resulting in the decomposition of Cu-EDTA into six intermediates. Meanwhile, SEM and XPS analyses revealed that Cu ions released during the degradation of Cu-EDTA are deposited on the limestone surface as Cu(OH) 2 and Cu 2 (OH) 2 CO 3 . In addition, the initial pH and co-existing ions have a weak effect on the system. Finally, a one-month continuous flow experiment showed that the degradation efficiency of Cu-EDTA was about 95.0 % and the removal efficiency of Cu ions was 40.0 %. In conclusion, this study provides a new approach for the destruction of metal complexes and the removal of heavy metals.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Mengxi Zhao,Changjun Zou
In the process of flue gas desulfurization, the dissolution of limestone is an important reaction control step. In this study, we try to improve the dispersion and solubility of desulfurizer based on introducing hydrophilic material to prompt desulfurization efficiency. Firstly, hydrophilic β-cyclodextrin was introduced onto the surface of CaCO 3 nanoparticles to improve the dispersion of nanoparticles. The same concentration of limestone slurry, CaCO 3 nanofluids and modified CaCO 3 nanofluids were prepared. The stability experiments indicated that the dispersion of modified CaCO 3 nanofluid was much better than limestone slurry and CaCO 3 nanofluids because of hydrophilic groups. Acid titration experiments indicated that the conversion rate of the modified CaCO 3 nanofluid could reach 99.2%. Combined with the theory of shrinking core model, the dissolution rate of modified CaCO 3 nanofluid was 0.0103 s −1 , which was 73.14% higher than that of limestone slurry. The desulfurization experiments indicated that the desulfurization effect of high concentration CaCO 3 nanofluid was no longer obvious because of the agglomeration of nanoparticles, while the desulfurization effect of modified CaCO 3 nanofluid was much better than that of limestone slurry and CaCO 3 nanofluid. The maximum saturated sulfur capacity and desulfurization rate of 7 wt% modified CaCO 3 nanofluids were 81.38 mg/mL and 98.23%.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Xilong Peng,Wenjin Chen,Zongjian He,Dan Li,Heng Liu,Hong Jin,Guigen Zhou,Feigao Xu
Reducing copper content in copper-containing water is a worldwide environmental problem. It has been shown that hydroxyapatite (HAP) has a significant adsorption effect on heavy metals (including Cu 2+ ). In this study, doped HAP-coated-limestone was synthesized using waste limestone, diammonium hydrogen phosphate and two kinds of chloride (Mg 2+ , Sr 2+ ). The materials were characterized by X-ray diffraction (XRD), Fourier transform infrared spectrophotometry (FTIR), thermogravimetric analysis (TGA), Brunner-Emmet-Teller (BET) measurements and scanning electron microscope (SEM). It was found that the structure of Mg 2+ and Sr 2+ doped HAP-coated-limestone was similar to that of HAP-coated-limestone. The surface of doped HAP-coated-limestone is rougher, and the specific surface area is larger than that of HAP-coated-limestone. Some factors have been investigated affecting the uptake behavior, such as doped element, contact time, temperature and Cu 2+ concentration to optimize the conditions. The adsorption isotherms of Langmuir and Freundlich were studied, and it was proved that the adsorption isotherm of Langmuir was more consistent with the adsorption process of doped HAP-coated-limestone. The quasi-second-order dynamics can be better used to describe the experimental results compared with quasi-first-order dynamics. At the temperature of 30 °C, the adsorption capacity of HAP-coated-limestone for Cu (II) is 90.90 mg·g −1 , while the adsorption capacity is 214.20 and 121.61 mg·g −1 for Mg 2+ and Sr 2+ doped HAP-coated-limestone, respectively. Through the calculation of thermodynamic parameters, the results show that the adsorption process of Cu (II) on HAP-coated-limestone and doped HAP-coated-limestone becomes easier with the increase of temperature in a certain temperature range. The adsorption process on HAP-coated-limestone and doped HAP-coated-limestone is spontaneous and endothermic.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2025
·
IF 13.1
Jing Qiao,Chunsheng Zhou,Jingjing Feng,Miao Miao,Yanliang Ji,Linan Gu
Limestone powder (LS) with large particle sizes is widely used, but its effect on water migration behavior remains unclear. This study investigates the influence of LS and viscosity-enhancing admixtures (VEAs) on the water migration behavior and water distribution in fresh cement paste using 1 H low-field nuclear magnetic resonance (LF-NMR). Results indicate that LS increases the size of water migration channels, accelerates the water migration rate, and raises the bleeding ratio, while VEAs substantially mitigate the effects of LS. Compared to polyacrylamide, cellulose ether significantly slows down the water migration rate before 40 min, thereby reducing the bleeding ratio. Additionally, relaxation times were found to decrease during bleeding and can reflect the sedimentation process. It is confirmed that the pore structure of fresh paste exhibits fractal characteristics, with the fractal dimension closely correlating with water migration rates. The underlying mechanisms and their implications on material behavior are thoroughly analyzed and discussed.
研究领域:
材料科学
·
土木工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）