Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Qi Tan,Yiwen Liu,Ruifeng An,Heping Wu,Zhiqiang Tian,Bingliang Gao
Reducing greenhouse gas emissions is a crucial step in mitigating global warming. Carbon dioxide (CO 2 ) represents one of the most pivotal greenhouse gases contributing to climate change. Many researchers are actively engaged in the development of effective and reversible CO 2 absorbents to control and reduce CO 2 gas emissions. In this paper, we synthesized a series of molecular solvents (MSs) based on the superbase 1,5-diazabicyclo [4.3.0]-5-nonene (DBN) and used them for CO 2 capture. The CO 2 capture capacity of MSs composed of DBN and different alcohols was systematically investigated, with DBN-Methanol (1:1.25) demonstrating superior absorption performance by achieving a maximum absorption capacity of 0.263 g CO 2 /g MS. The effects of temperature, pressure, the molar ratio of the hydrogen bond acceptor (HBA) to hydrogen bond donor (HBD), and moisture on the absorption process were studied. The experimental results were corroborated by NMR spectra analysis and FTIR spectra analysis, confirming that these MSs can effectively react with CO 2 to produce carbonate and carbamate compounds through synergistic absorption involving hydroxyl group as primary component and amino group as secondary component. In addition, it is worth noting that the MSs studied in this work exhibit only glass transition at low temperatures and transform into ionic liquids (ILs) after capturing CO 2 , resulting in a significant increase in conductivity and demonstrating considerable electrochemical potential.
研究领域:
化学
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环境科学
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DOI
高影响因子
Reactions
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2024
·Vol. 5
·期 4
·812-822
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IF 2.2
Joseph Dean,Natalia Buckler Reinoso,Francesco Spiedo,Carola Romero Fernández,Bhaven Patel
Flow chemistry has shown significant versatility over the last two decades, offering advantages in efficiency, scalability, and sustainability. In this study, the continuous stirred tank reactor (CSTR) was used to optimise the synthesis of α-hydroxyphosphonates via the Pudovik reaction and their subsequent conversion to phosphates through the phospha-Brook rearrangement. The study highlights that using CSTRs allows for better control over reaction parameters, leading to reduced reaction times and improved yields compared to traditional batch methods. The optimised conditions successfully facilitated a range of organophosphates, including electron-rich and electron-poor derivatives, with high efficiency. Additionally, a one-pot tandem process combining the Pudovik reaction and the phospha-Brook rearrangement was developed, reducing reaction times to two hours while maintaining comparable yields. This work demonstrates the potential of CSTRs in flow chemistry for synthesising complex organophosphorus compounds, achieving higher reaction yields and shorter reaction times, highlighting the effectiveness of continuous flow methodologies.
研究领域:
有机化学
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合成化学
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流程优化
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DOI
高影响因子
RSC Advances
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2021
·Vol. 11
·期 50
·31226-31234
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IF 3.361
Dapeng Li,Peng Zhang,Suxiang Ge,Guofu Sun,Qin He,Wenjun Fa,Yun Li,Juntao Ma
Exploring the environmentally friendly and low-cost synthesis strategies of phthalocyanine (Pc) crystals in just one step is an absolute challenge. The solvothermal synthesis of phthalocyanine crystals shows the advantages of high-quality crystalline products, facile reaction and purification, and low cost. Nevertheless, only a few metal phthalocyanine crystals have been successfully synthesized via solvothermal reactions. In this study, we found that the crystalline β metal-free phthalocyanine needles could be directly prepared via the tetrapolymerization of phthalodinitrile catalyzed by DBU in solvothermal reactions. Similar to the preparation of β-phthalocyanine crystals, the α metal-free phthalocyanine crystals with the specific multiply-laminated structures can be obtained through solvothermal reactions assisted by DBN. SEM characterization showed that the individual β metal-free phthalocyanine has a well-defined quadrangular shape with smooth faces. However, the α metal-free phthalocyanine exhibits a distinctive undulating surface morphology. Both phthalocyanines showed satisfactory thermal stability (from room temperature to about 300 °C), excellent resistance to acid/alkali solution, and fast photoelectric response properties (order of magnitude of response time, 10−6 s) as tested by TG-DSC and TPV, respectively. It is noted that ethanol was used as the reaction medium and the resulting phthalocyanine crystals can be facilely purified using hot ethanol to dissolve the impurities adsorbed on the surfaces of phthalocyanine crystals. Compared to the traditional methods, no re-crystallization operation was carried out for our method. To the best of our knowledge, this is the first report on the solvothermal synthesis of metal-free phthalocyanine crystals with controllable crystal form adjusted by DBU/DBN in one step.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2025
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IF 4.3
Chunrui Rong,Dongxia Yan,Jiabao Li,Jian Feng,Jiayu Xin,Qing Zhou,Yi Li,Junli Xu,Xingmei Lu
The increase in the usage of polyethylene terephthalate (PET) leads to the generation of a large amount of waste, which may cause carbon emissions and waste of petroleum resources. The methanolysis method has attracted global attention, but limited by high reaction temperature and excessive use of methanol. We report here an efficient catalyst, tetramethylguanidine/1,5-diazabicyclo[4.3.0]-5-non-ene (TMG/DBN), converting waste PET into regenerated dimethyl terephthalate (rDMT) under 100 °C with almost equivalent methanol, achieving 100 % PET conversion and 93.1 % yield of rDMT. A series of analytical methods and theoretical calculations were used to reveal the enhanced interaction between the catalyst and reactants, which facilitates the degradation of PET at low methanol dosages. In addition, a kinetic model was also developed with a relatively low activation energy of 84.9 kJ/mol. This work provides an effective strategy for the up-grading recycling of waste PET under mild reaction conditions.
研究领域:
材料科学
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环境科学
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化学工程
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
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IF 5.4
Manman Liu,Chen Cheng,Luyao Wang,Zhaohui Qiu,Sheng Liu,Wei Chen,Guangyi Liu
Under the traditional sulfhydryl collector system, the flotation enrichment of sphalerite requires the addition of copper ions to pre-activate sphalerite, and the separation of sphalerite and pyrite can be realized under high alkali conditions, which is not environmentally friendly. Therefore, it is urgent to develop highly selective collectors to achieve green separation of sphalerite and pyrite without copper ion activation and under low alkali conditions. In this study, 2-dibutylamino-4(1 H)-thione-6-thiol-1,3,5-triazine (DBN) was first selected as a specific collector for flotation separation of sphalerite from pyrite, and the selective hydrophobic mechanism of DBN on sphalerite surface was emphatically investigated. UV spectra showed a selective affinity of DBN towards zine ions rather than iron ions. The results of adsorption capacity indicated that under pH 4.0 ∼ 6.0, the adsorption amount of DBN on sphalerite was much higher than that on pyrite. In-situ atomic force microscopy (AFM) images combined with Contact Angle distinctly exhibited that the self-assembly of DBN on sphalerite improved its surface hydrophobicity. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed that DBN chemisorbed on sphalerite surface via bonding DBN’s exo -S atom with surface Zn atom. Due to the selective adsorption, DBN efficiently floated out sphalerite from pyrite at natural pH (∼5.9) in the absence of extra agents such as lime, activators and depressants. Therefore, DBN achieved the green separation and enrichment of sphalerite from pyrite, which offered a novel insight for developing green and efficient collectors.
研究领域:
矿物加工工程
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环境科学
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2024
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IF 5.8
Yutong Huo,Zheng Zhong,Shitong Liu,Shitong Sun,Weiguo Yao,Quanming Li,Yanli Dou
Considering the requirement of environmental and bio-friendliness of flame retardants, there is an urgent need to develop efficient flame retardants based on low-toxicity raw materials. Herein, a nano-fold structure DBN@CoMo-LDH was successfully synthesized by combining layered double hydroxides (LDHs) with hexagonal boron nitride (h-BN), through a sacrificial template approach involving ion-exchange interaction at atmospheric pressure. Thanks to the better compatibility and strong interfacial interactions of hybrids in matrix, epoxy resin (EP) composites can exhibit superior flame retardancy and smoke suppression without loss of mechanical properties. The enhancement and mechanism of fire safety of EP composites were investigated through cone calorimetric test, condensed-phase residue analysis, and gas-phase product analysis. Compared to EP, the peak heat release rate (pHRR), peak smoke production rate (pSPR), total smoke production (TSP), carbon monoxide production rate (COP) and carbon dioxide production rate (CO 2 P) of EP/4DBN@CoMo-LDH were reduced by 37.77 %, 62.96 %, 50.45 %, 45.71 % and 40.98 %, respectively. DBN@CoMo-LDH not only promoted the rapid generation of a dense carbon layer, but also effectively suppressed the release of gas phase products. Furthermore, it demonstrates excellent antimicrobial properties against both Staphylococcus aureus and Escherichia coli . Moreover, the unique nano-fold structure can provide a good thermal conduction path in the matrix, improving the thermal conductivity of EP. This study offers a feasible approach for designing high-performance flame retardants, and suggests their potential application in multifunctional EP composites.
研究领域:
材料科学
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环境科学
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生物学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Jiabao Li,Dongxia Yan,Xiujie Cheng,Chunrui Rong,Jian Feng,Xin Feng,Jiayu Xin,Qing Zhou,Yi Li,Junli Xu,Xingmei Lu
The methanolysis of polyethylene terephthalate (PET) can address the environmental pollution and resource waste caused by waste PET, and the obtained monomer dimethyl terephthalate (DMT) is easy to separate and purify. However, conventional methanolysis of PET usually uses metal-containing catalysts, resulting in metal residues in the degradation products, which affects subsequent high-value utilization. Meantime, the reaction conditions of high temperature and high pressure promotes the occurrence of side reactions and reduces the yield of the main products. Herein, the nonmetallic deep eutectic solvent (DES) 1,5-diazabicyclo [4.3.0]-5-nonene (DBN)/Phenol was employed as a catalyst for PET methanolysis. 100% PET conversion and 95.3% DMT yield were obtained at 130 °C for 1 h. The possible reaction mechanism was investigated by combining NMR, FT-IR, GPC analysis, and DFT calculations. DBN and phenol were connected through N–H–O hydrogen bonding, where the hydrogen atom interacted with the carbonyl oxygen of PET and the oxygen atom activated the hydroxyl group of methanol. Additionally, GPC analysis showed that the dissolution and degradation of PET were simultaneous, which enhanced mass transfer and facilitated the reaction. The kinetic studies showed that PET methanolysis followed the first-order kinetic model with an activation energy of 103.3 kJ/mol, which was lower than the literature-reported value. This research provides an efficient nonmetallic deep eutectic solvent catalyst for PET methanolysis, which solves the problem of metal residues in the degradation products and reduces the reaction temperature. It is of great significance to simplify the purification steps and improve the economy of regeneration.
研究领域:
化学工程
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环境科学
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材料科学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Jia Liu,Houfang Lu,Yingying Liu,Kejing Wu,Binshen Wang,Yingming Zhu,Bin Liang
As a highly toxic gas, H2S is conventionally removed via a chemical absorption process. However, the high regeneration energy is still a challenge. 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN)/polyethylene glycol dimethyl ether (NHD) solution was developed as an efficient nonaqueous phase change absorbent for the removal of H2S with low energy consumption. A homogeneous DBN/NHD solution turns into two immiscible liquid phases upon the absorption of H2S, which results from the higher polarity of the product compared to that of the original solution. The loading capacity of H2S can reach 0.16 g·g–1 solvent even under a H2S partial pressure of 10 kPa at 30 °C. After absorption, more than 94% of the absorbed H2S is concentrated in the lower phase, which can be regenerated at 90 °C with an energy consumption estimated to be 1.69 GJ·t–1 H2S. The regeneration energy is 58% lower than that of 30 wt % aqueous solution of N-methyldiethanolamine. 81% of the initial H2S loading was maintained after 4 absorption–desorption cycles. In addition, the selectivity of DBN/NHD solution to absorb H2S from N2 containing H2S and CO2 or from N2 containing H2S and CH4 was investigated. It shows that the selectivity increases with the increase in the volume ratio of H2S to CO2, which can be as high as 27.8 when the ratio is 1:1. CH4 cannot be absorbed in the DBN/NHD solution in the presence of H2S and N2.
研究领域:
化学工程
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环境科学
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材料科学
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
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2018
·Vol. 36
·期 4
·293-298
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IF 2.378
Wei Li,Weiguo Cheng,Xia Yang,Qian Su,Lihui Dong,Pan Zhang,Yunan Yi,Bin Li,Suojiang Zhang
In this work, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]-5-nonene (DBN), and imidazole (MIM)-derived bromide ionic liquids (ILs) were synthesized and used to catalyze the cycloaddition reactions of carbon dioxide (CO 2 ) with several kinds of epoxides to form cyclic carbonates. The DBU derived bromide ionic liquid system was found to have the best catalytic activity among all the tested ILs. The influences of reaction conditions (including temperature, pressure and reaction time) on the reaction of CO 2 to propylene oxide (PO) were studied to show the best conditions of 120 °C, 1 MPa, 2.5 h catalyzed by 2 mol% DBU-derived bromide ionic liquid, with the conversion of PO and the selectivity of propylene carbonate (PC) reaching 99% and 99%, respectively. Under the optimum reaction conditions, the ionic liquid system could be reused at least five times without decrease in selectivity and conversion. NMR spectroscopy and DFT calculations were used to reveal the hydrogen-bond interaction between ionic liquids and reagent, based on which the reaction mechanism was proposed.
研究领域:
化学
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催化
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绿色化学
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材料科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）