Engineering
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2024
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IF 10.1
Jinjing Huang,Xia Liu,Kaixing Fu,Shengyun Yang,Shiqing Zhou,Jinming Luo
The valorization of Chinese medicine residues (CMRs) into high-value-added products, such as microcrystalline cellulose (MCC), has garnered significant interest in the current post-pandemic era, particularly in regions where Chinese medicine (CM) is widely utilized (i.e., Southeast Asia). In this study, we propose a facile and economical protocol for selectively extracting MCC from CMRs via one-step direct peroxymonosulfate (PMS) oxidation without the need for intricate steps. Importantly, our proposed protocol has been verified to be versatile and can be applied to various solid waste sources rich in cellulose, with an average extraction rate of 75%. Analysis using the Fukui index revealed that the β-O-4 bond, the aromatic ring in lignin, specific O sites in hemicellulose, and the amorphous region of cellulose are more susceptible to electrophilic attack by PMS than to reactions involving HO • , SO 4 •− , or 1 O 2 . Leveraging this distinct mechanism, the extracted MCC demonstrated ultrahigh purity (∼95%) and crystallinity (∼85.36%). Overall, our work involves transforming solid waste into high-value products through the provision of a technical solution, with the potential for onsite application. This represents a significant advancement to the valorization of CMRs, particularly in providing theoretical guidance for accelerating the recycling of waste materials.
研究领域:
环境科学
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材料科学
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化学工程
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废物管理
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药学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Yanyu Song,Xianbo Sun,Long D. Nghiem,Jun Duan,Wen Liu,Yongdi Liu,Zhengqing Cai
Building a heterojunction is a fascinating option to guarantee sufficient carrier separation and transfer efficiency, but the mechanism of charge migration at the heterojunction interface has not been thoroughly studied. Herein, MIL-53(Fe)/Bi 4 O 5 I 2 photocatalyst with a Z-scheme heterojunction structure is constructed, which achieves efficient photocatalytic decontamination under solar light. Driven by the newly-built internal electric field (IEF), the formation of Fe-O-Bi electron migration channel allows for rapid separation and transfer of charge carriers at the heterojunction interface, confirmed by the material characterization and density functional theory (DFT) calculation. The narrower band gap and improved visible light response also contribute to the enhanced photocatalytic activity of composite materials. With levofloxacin as the target pollutant, the optimal MIL-53(Fe)/Bi 4 O 5 I 2 achieves complete removal of pollutant within 150 min, the photocatalysis rate of which is ca. 4.4 and 26.0 times that of pure Bi 4 O 5 I 2 and MIL-53(Fe), respectively. Simultaneously, the optimal composite material exhibits satisfactory photodegradation of seven fluoroquinolones, and the photocatalysis rates are as follows: lomefloxacin > ciprofloxacin > enrofloxacin > norfloxacin > pefloxacin > levofloxacin > marbofloxacin. DFT calculations reveal a positive relationship between degradation rate and Fukui index (ƒ 0 ) of main carbon atoms in seven fluoroquinolones. This study sheds light on the existence of electron migration channels at Z-scheme heterojunction interface to ensure sufficient photoinduced carrier transfer, and reveals the influence of pollutant structure on photolysis rate.
研究领域:
材料科学
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环境科学
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化学
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光化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Mude Zhu,Yi Tang,Xueqin Chen,Linli Xu,Xiaoyun Fan
Constructing a chemical bond between the catalysts’ interfaces can establish a fast electron diffusion path and improve interfacial charge transport, thus produce a high efficiency in the catalytic field. We innovatively incorporate the humic acid (HA) and SrBi 2 B 2 O 7 (SBBO) to degrade oxytetracycline (OTC) under ball milling (BM), the degradation efficiency of OTC for SBBO/HA under BM is 93.17 % and its pseudo-first-order kinetic constant is 0.0434 min −1 , being 1.41 times than the sum of rate constant for HA (0.00826 min −1 ) and SBBO (0.0225 min −1 ), and 5.26 times than that for BaTiO 3 (0.00825 min −1 ), illustrating their outstanding synthetic effect of SBBO and HA on piezoelectric degradation of OTC. The mechanism of enhanced piezoelectric activity was attributed to the B-N bond which enhances the local polarized electric field improving electron transfer and contributes to the generation of •O 2 – and •OH. The possible degradation pathways involving bonds cleavage, ring-opening, and dehydroxylation process were proposed based on LC-MS and Fukui index calculation. The toxicity of intermediates generated during the piezoelectric catalysis was predicted and investigated by T.E.S.T. software and mung bean growth. This study provides a new technology of enhancing piezoelectric catalytic activity by combining HA, SBBO and BM and clarifies the mechanism in detail.
研究领域:
环境科学
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材料科学
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化学工程
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催化
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水处理
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2023
·
IF 8.3
Zhizhuo Chai,Jingquan Wang,Yixue Dai,Erdeng Du,Hongguang Guo
Methylisothiazolinone (MIT) is widely used in daily chemicals, fungicides , and other fields and its toxicity has posed a threat to water system and human health. In this study, ultraviolet (UV)/trichloroisocyanuric acid (TCCA), which belongs to advanced oxidation processes (AOP), was adopted to degrade MIT. Total chlorine attenuation detection proved that TCCA has medium UV absorption and a strong quantum yield (0.49 mol E −1 ). At a pH of 7.0, 93.5% of MIT had been decontaminated after 60 min in UV/TCCA system (k obs = 4.4 × 10 −2 min −1 , R 2 = 0.978), which was much higher than that in the UV alone system and TCCA alone system, at 65% (1.7 × 10 −2 min −1 , R 2 = 0.995) and 10% (1.8 × 10 −3 s −1 , R 2 = 0.915), respectively. This system also behaved well in degrading other five kinds of contaminants. Tert-butanol (TBA) and carbonate (CO 3 2− ) were separately used in quenching experiments, and the degradation efficiency of MIT decreased by 39.5% and 46.5% respectively, which confirmed that HO• and reactive chlorine species (RCS) were dominant oxidants in UV/TCCA system. With TCCA dosage increasing in a relatively low concentration range (0.02–0.2 mM) and pH decreasing, the effectiveness of this AOP system would be strengthened. The influences of coexisting substances (Cl − , SO 4 2− , CO 3 2− , NO 2 − and NO 3 − ) were explored. MIT degradation pathways were proposed and sulfur atom oxidation and carboxylation were considered as the dominant removal mechanisms of MIT. Frontier orbital theory and Fukui indexes of MIT were employed to further explore the degradation mechanism.
研究领域:
环境科学
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化学工程
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水处理
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高级氧化过程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）