RSC Advances
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2021
·Vol. 11
·期 53
·33626-33636
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IF 3.361
Leliang Wu,Yiting Lin,Yimin Zhang,Peng Wang,Mingjun Ding,Minghua Nie,Caixia Yan,Shiyao Chen
Alkaline substances could activate peroxymonosulfate (PMS) for the removal of organic pollutants, but relatively high alkali consumption is generally required, which can cause too high pH of the solution after the reaction and lead to secondary pollution. Within this study, PMS activated by a relatively low dosage of Ca(OH)2 (1 mM) exhibited excellent efficiency in the removal of bisphenol S (BPS). The pH of the solution declined to almost neutral (pH = 8.2) during the reaction period and conformed to the direct emission standards (pH = 6–9). In a typical case, BPS was completely degraded within 240 min and followed the kinetics of pseudo-first-order. The degradation efficiency of BPS depended on the operating parameters, such as the Ca(OH)2, PMS and BPS dosages, initial solution pH, reaction temperature, co-existing anions, humic acid (HA), and water matrices. Quenching experiments were performed to verify that singlet oxygen (1O2) and superoxide radicals (O2˙−) were the predominant ROS. Degradation of BPS has been significantly accelerated as the temperature increased. Furthermore, degradation of BPS could be maintained at a high level across a broad range of pH values (5.3–11.15). The SO4−, NO3− did not significantly impact the degradation of BPS, however, both HCO3− and HA inhibited oxidation of BPS by the Ca(OH)2/PMS system, and Cl− had a dual-edged sword effect on BPS degradation. In addition, based on the 4 identified intermediates, 3 pathways of BPS degradation were proposed. The degradation of BPS was lower in domestic wastewater compared to other naturals waters and ultrapure; nevertheless, up to 75.86%, 77.94% and 81.48% of BPS was degraded in domestic wastewater, Yaohu Lake water and Poyang Lake water, respectively. Finally, phenolic chemicals and antibiotics, including bisphenol A, norfloxacin, lomefloxacin hydrochloride, and sulfadiazine could also be efficiently removed via the Ca(OH)2/PMS system.
研究领域:
环境科学
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化学工程
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DOI
PubMed
高影响因子
MATERIALS AND STRUCTURES
·
2023
·Vol. 56
·期 1
·1-15
·
IF 3.8
Song Yufeng,Zhang Yi,Shen Siyi,Pan Chenyu,Yan Dongming,Wang Zhiguang,Wang Su,Ruan Shaoqin
This study aims to explore the effects of different Ca(OH) 2 contents on the mechanical performance and corrosion behaviors of steel in Calcium sulfoaluminate (CSA) cement, where compressive strength, corrosion potentials of reinforcements, corrosion current density, pH of pore solution as well as mortar resistivity of CSA/Ca(OH) 2 mortar were researched, and the corrosion behaviors were further interpreted by the clarification of hydration phases through microstructural analyses. The initial results highlighted the positive effects of using adequate Ca(OH) 2 (~ 6%) in CSA mortar in terms of strength, yet its excessive addition could delay the subsequent hydration reaction of CSA. Meanwhile, with an increased quantity of Ca(OH) 2 , the amount of some hydration phases, such as Al(OH) 3 reduced, resulting from their reaction with Ca(OH) 2 . Finally, the corrosion current density increased with the reduced mortar resistivity when the reinforcement in CSA/Ca(OH) 2 system was corroded, and their relationship was also provided in this study.
研究领域:
建筑材料学
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腐蚀科学
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材料科学
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DOI
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Zijing Wang,Changjuan Mo,Sixuan Xu,Shanshuai Chen,Tiansheng Deng,Wanbin Zhu,Hongliang Wang
The catalytic conversion of carbohydrate to platform chemicals, e.g. lactic acid (LA), is the key to unlock the potential of biomass. In this study, we report that the combination of Ba(OH) 2 and Ca(OH) 2 can efficiently catalyse high-concentration (> 0.5 M) of glucose to relatively high yield of LA (> 40 %) under mild conditions (60 °C). Both glucose conversion and LA yield were sensitive to the pH of the catalytic system. A high loading of Ba(OH) 2 led to a high initial pH of the reaction solution, resulting in serious side reactions. While, a low loading of Ba(OH) 2 led to a quike decrease of OH − and Ba 2+ both of which were continuously consumpted by the formed LA. The combination of Ca(OH) 2 with Ba(OH) 2 could significantly improve LA yield, since Ca(OH) 2 , with limited solubility, could act as a controlled-release catalyst for the real-time supply of OH − and Ca 2+ . OH − was indispensable for glucose isomerization to fructose as well as for fructose retro-aldol reaction to C 3 intermediates. Ca 2+ could combine with LA to form stable calcium lactate, liberating Ba 2+ to catalyse the conversion of C 3 intermediates to LA. Under the preliminary optimized reaction conditions, the yield of LA could be reached to 42.55 % and 38.32 % from 0.5 M and 1 M glucose, respectively. This catalytic system has advantages of mild reaction condition, short reaction time, and capable of conversion of high-concentration substrates, enabling it with a great potential for practical applications.
研究领域:
生物化学
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可再生资源化学
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DOI
高影响因子
POWDER TECHNOLOGY
·
2023
·
IF 5.2
Yuxiang Cheng,Zhongjie Shen,Feng Lv,Dayang Wan,Yongchuan Gao,Yiru Yang,Haifeng Lu,Zhenghua Dai,Haifeng Liu
During the Ca(OH) 2 /CaO thermochemical energy storage process, the cyclability of reactions and the consolidation properties of powder storage are important issues to consider. In this study, experiments were conducted to assess the evolution of reaction conversion, particle size and penetration resistance of Ca(OH) 2 /CaO powder fixed bed. The results revealed that the final conversions of both the hydration and dehydration reactions stabilized between 70 and 80%. The particle size distributions of Ca(OH) 2 increased initially and then decreased with the increasing cycle number and degree of dehydration. The dehydration conversion was the dominant factor for changing Ca(OH) 2 bed penetration resistance force. The particle size and penetration resistance of the CaO bed remained stable during long-term storage at high temperatures. The theoretical analysis of the inter-particle forces agreed with the trend of the experimental results, with particle size and moisture content being the main factors affecting cohesion.
研究领域:
材料科学
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能源工程
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Liwen Shen,Feiyang Zhao,Huijuan Liu,Jicheng Li,Yang Lu,Jun Liu,Nianzhao Gao,Shuangfei Xiang,Shujun Zhao,Guocheng Zhu,Parpiev Khabibulla,Juramirza Kayumov,Feiya Fu,Xiangdong Liu
The agricultural industry produces a substantial volume of rice straw (RS) annually, highlighting the importance of recycling RS for sustainable materials. However, the poor interfacial compatibility between RS and polymers often leads to drawbacks in their composites, such as water-swelling and limited tensile strength. Here, we propose a novel approach using Ca(OH) 2 that offers several distinct advantages: enhancement of interfacial compatibility, elimination of the need for water washing, and formation of calcified hybrid particles on fiber surfaces by capturing CO 2 from the atmosphere. The non-washing calcified rice straw (NCRS) fibers were used to fabricate composites with unsaturated polyester resin (UPR), resulting in NCRS/UPR composites exhibiting significant enhancements in water resistance and mechanical properties compared to RS/UPR composites. The NCRS/UPR composites achieved a water absorption rate below 25 %, thickness swelling rate below 10 %, and tensile strength of 19.9 MPa. This work comprehensively explored the mechanism underlying these achievements through experimental studies. Findings suggest that CaCO 3 particles involving with released lignin act as an interfacial bridge between RS fiber surface and UPR, resulting in significantly improved properties. This approach demonstrates promising prospects as a simple and eco-friendly methodology for manufacturing RS-based composite materials.
研究领域:
材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
Advanced Sustainable Systems
·
2025
·
IF 6.1
Yu Ren,Youhao Zhang,Zizheng Zhou,Yi Fang,Yuzhuo Wang,Yingjie Li
Ca(OH) 2 can be used in CO 2 uptake from the flue gas in fossil-fired power plants. Compared with indirect method where Ca(OH) 2 is first converted into CaO and then uptakes CO 2 , direct CO 2 uptake by Ca(OH) 2 occurs at lower temperature, leading to slighter sintering. However, the direct CO 2 uptake capacity of Ca(OH) 2 should be further enhanced. In this study, Ca(OH) 2 is doped with Mn to improve its direct CO 2 uptake capacity in carbonation-calcination-hydration cycles. The cyclic tests are conducted in a triple fixed-bed reactor. The mechanism of CO 2 adsorbed on Mn-modified Ca(OH) 2 is determined by density functional theory calculations. In the first cycle, Mn-modified sorbents acquire highest carbonation conversion at 400 °C, which is 40 °C lower than Ca(OH) 2 . The modified Ca(OH) 2 with Ca/Mn molar ratio of 100:0.75 exhibits the best performance, and its carbonation conversions reach 0.76 and 0.59 in the 1st and 20th cycles, respectively, which are 28% and 18% higher than those of Ca(OH) 2 . Furthermore, carbonation conversion of this Mn-modified Ca(OH) 2 decreases by within 1.00% from cycle 5 to 20. Mn addition boots oxygen vacancy, increases the surface area and pore volume, and reduces the energy barrier for carbonation of Ca(OH) 2 . Mn-modified Ca(OH) 2 as CO 2 sorbent appears promising.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Jiawen Wu,Xiaonan Sun,Junting Wu,Xue Yu
This study proposes a green and simple strategy for efficiently removing heavy metals from wastewater by activating biochar with eggshell and in-situ generating CaO/Ca(OH) 2 . Characterization results revealed that the composite carbon material (BCEg15) successfully incorporated CaO/Ca(OH) 2 active sites compared to the raw biochar (BC). Additionally, eggshell activation increased the specific surface area and pore volume of BCEg15 by 4.36 and 6.80 times, respectively, compared to BC. These structural enhancements increased the maximum adsorption capacity of BCEg15 for Pb 2+ and Cd 2+ by 20.68 and 42 times, respectively, compared to BC. Importantly, the loading of CaO and Ca(OH) 2 significantly enhanced the ion exchange and mineral precipitation capacities of the biochar. For instance, compared to BC, the adsorption capacities of BCEg15 attributed to ion exchange (Q e ) for Pb 2+ and Cd 2+ rose by 403.12 mg/g and 197.65 mg/g, respectively, while the adsorption capacities attributed to mineral precipitation (Q p ) increased by 19.60 times and 45.20 times, respectively. BCEg15 demonstrated excellent reusability, maintaining adsorption capacities of 461.18 mg/g for Pb 2+ and 265.26 mg/g for Cd 2+ after five cycles. Additionally, BCEg15 outperformed commercial activated carbon in treating heavy metals from desulfurization wastewater from coal-fired power plants, achieving a removal efficiency of 99.98 % compared to 48.22 %. The primary mechanisms by which BCEg15 removes Pb 2+ and Cd 2+ were identified as ion exchange, mineral precipitation, complexation with oxygen-containing functional groups, and interactions with π electrons. Density functional theory (DFT) was utilized to delve deeper into the microscopic mechanisms of adsorption. The findings showed that the O-top site of CaO exhibited the greatest stability for heavy metal adsorption. Electron density difference maps and partial density of states (PDOS) results revealed a denser electron cloud and greater orbital overlap between CaO and Pb 2+ compared to Cd 2+ , suggesting a higher affinity and adsorption capacity for Pb 2+ , consistent with the experimental findings. This study presents an effective method for preparing adsorbents capable of removing Pb 2+ and Cd 2+ from wastewater and offers theoretical insights into the adsorption mechanisms of metal oxide-incorporated biochar.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2022
·
IF 8.907
Zhiguo Bian,Yingjie Li,Feifei Wang,Yi Fang,Jianli Zhao,Jianhui Qi
CaO/Ca(OH) 2 heat storage system is one of the most promising candidates for large-scale thermochemical heat storage at temperature of 300–600 °C. In this work, the CaO/Ca(OH) 2 heat storage performances of the Ce- and Mn-doped CaO were investigated and the mechanisms of promoting hydration by Ce and Mn doping were determined via density functional theory (DFT) calculations. The Mn-doped CaO exhibits the higher hydration conversion than CaO and Ce-doped CaO. The structural parameters, partial density of states, electron differential densities and energy barriers during hydration stage on the CaO, Ce- and Mn-doped CaO surfaces were compared to clarify the effects of Ce and Mn on hydration of CaO. The results show the detailed hydration reaction pathways on the CaO, Ce- and Mn-doped CaO surfaces. During the H 2 O adsorption stage, H 2 O on the Ce-doped CaO surface approaches the Ca atom first, while H 2 O on the Mn-doped CaO surface approaches the O s atom first. The adsorption energy for Ce- and Mn-doped CaO are −1.612 and −0.896 eV, respectively, which are higher than that for CaO. The doping of Ce and Mn accelerates the H 2 O adsorption on the CaO surface. The Mn doping causes the 84.3 % reduction in the energy barrier for hydration of CaO and the reduction by Mn doping is larger than that by Ce doping. Thus, Mn-doped CaO exhibits the higher hydration reactivity and hydration conversion than CaO and Ce-doped CaO. The DFT calculations determined the promotion mechanism of Ce and Mn doping on the hydration of CaO in CaO/Ca(OH) 2 heat storage.
研究领域:
材料科学
·
热能储存
·
计算化学
✓ 已验证
DOI
高影响因子
Environmental Technology & Innovation
·
2018
·
IF 0
Jiaorong Yan,Feixiang Zhou,Ying Zhou,Xianghao Wu,Qiulian Zhu,Huayan Liu,Hanfeng Lu
The removal of NO x with low oxidation degree, low temperature, and high vapor content from small coal-fired boiler emission through selective catalytic reduction is difficult. This study investigated liquid oxidation and absorption to remove NO x systematically. Thermodynamic calculation showed that the equilibrium constants of the NO oxidation and NO x absorption reaction are high; thus, NO x treatment by liquid oxidation and absorption is feasible. Four oxidants (NaClO 2 , NaClO, H 2 O 2 , and KMnO 4 ) and four absorbents (Ca(OH) 2 , CaCO 3 , NaOH, and Na 2 CO 3 ) were used to study the reaction mechanism of the oxidation and absorption processes. Results show that NaClO 2 solution is the best oxidant, and the optimum pH value of the oxidation reaction is 5–6. The oxidation degree reaches 100% when the concentration of the NaClO 2 solution is 1.0%, and the oxidation degree can still reach approximately 50% when the concentration is 0.1%. Ca(OH) 2 slurry has the best absorption performance among the four kinds of absorbents. The NO x removal efficiency of Ca(OH) 2 slurry can reach approximately 70% when the oxidation degree is 50%. The removal efficiency is up to 80% when the oxidation degree is 100%.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Panpan Wang,Meiyu Shi,Bochen Zhao,Yuan Shu,Qiang Niu,Pengfei Zhang
Carbide residue, a highly alkaline industrial solid waste generated during acetylene production, is primarily composing of Ca(OH) 2 . In this study, a top-down solid-state redispersion strategy. By synergizing mechanochemical activation with surfactant capping, we achieving the recycling of carbide residue to synthesize Ca(OH) 2 -CTAB anosheet-based desulfurization agent. The resultant material exhibits a significantly enhancing BET specific surface area (30.2 m 2 ·g −1 ) and abundant pore architecture. Comparative evaluations with Ca(OH) 2 -P123 and raw carbide residue revealing the superior performance of the Ca(OH) 2 -CTAB adsorbent, demonstrating a sulfur dioxide adsorption capacity of 2.57 mmol·g −1 is a 2-fold improvement over untreating carbide residue. Furthermore, significantly extends the fixed-bed penetration time to 43869 seconds. Comprehensive characterization through TG, FTIR, BET, SEM, TEM, and AFM elucidating the relationship between the nanosheet morphology and its exceptional desulfurization performance. This work provides a green methodology for upcycling industrial alkaline waste into functional nanomaterials for environmental remediation.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 4
·1568
·
IF 3.4
Feng Wang,Yaoqi Gu,Jianrui Zha,Shuya Wei
Ca(OH)2nanoparticles are effective materials for cultural heritage restoration, hazardous substance absorption and photocatalyst. However, many methods are complex, and the particle sizes are usually above 80–100 nm, involving mediocre efficacy for application in the stone restoration field. In this work, Nano Ca(OH)2with diameters less than 70 nm and composited with Graphene Quantum Dots (GQDs) were successfully synthesized in aqueous media. The morphology and structure of the nanoparticles were investigated with TEM, HRTEM, XRD, Raman and FTIR. The particle size distribution and relative kinetic stability of the Ca(OH)2in ethanol were performed using a laser particle size analyzer and spectrophotometer. Firstprinciple calculations based on the spin-polarized density functional theory (DFT) were carried out to study the reaction process and combination model. The nanoparticles, as prepared, are composed of primary hexagonal crystals and high ammoniated precursors, which have a positive effect on reducing the grain size, and interacted with the GQDs hybrid process. According to the First-principle calculations results, the energy variation of the whole reaction process and the bonding mode between Ca(OH)2and GQDs can be understood better.Keywords:Ca(OH)2;Graphene Quantum Dots;DFT;complex;nanoparticles
研究领域:
材料科学
·
化学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2016
·
IF 2.628
Junjie Zhang,Fang Lu,Weiqiang Yu,Rui Lu,Jie Xu
Lactic acid is produced as a major byproduct during sorbitol hydrogenolysis under alkaline conditions. We investigated the effects of two different alkaline additives, Ca(OH) 2 and La(OH) 3 , on lactic acid formation during sorbitol hydrogenolysis over Ni/C catalyst. In the case of Ca(OH) 2 , the selectivity of lactic acid was 8.9%. In contrast, the inclusion of La(OH) 3 resulted in a sorbitol conversion of 99% with only trace quantities of lactic acid being detected. In addition, the total selectivity towards the C2 and C4 products increased from 20.0% to 24.5% going from Ca(OH) 2 to La(OH) 3 . These results therefore indicated that La(OH) 3 could be used as an efficient alkaline additive to enhance the conversion of sorbitol. Pyruvic aldehyde, which is formed as an intermediate during sorbitol hydrogenolysis, can be converted to both 1,2-propylene glycol and lactic acid by hydrogenation and rearrangement reactions, respectively. Notably, these two reactions are competitive. When Ca(OH) 2 was used as an additive for sorbitol hydrogenolysis, both the hydrogenation and rearrangement reactions occurred. In contrast, the use of La(OH) 3 favored the hydrogenation reaction, with only trace quantities of lactic acid being formed.
研究领域:
化学工程
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）