• Title/Summary/Keyword: green chemistry

Search Result 941, Processing Time 0.029 seconds

Fabrication of Ag/In2O3/TiO2/HNTs hybrid-structured and plasma effect photocatalysts for enhanced charges transfer and photocatalytic activity

  • Wang, Huiqin;Wu, Dongyao;Liu, Chongyang;Guan, Jingru;Li, Jinze;Huo, Pengwei;Liu, Xinlin;Wang, Qian;Yan, Yongsheng
    • Journal of Industrial and Engineering Chemistry
    • /
    • v.67
    • /
    • pp.164-174
    • /
    • 2018
  • The purpose of this work designed hybrid-structured and plasma effect photocatalyst of $Ag/In_2O_3/TiO_2/HNTs$ via sol-gel and photo-reduction methods. The structures, morphologies, optical and photoelectric performances of as-prepared photocatalysts were characterized via XRD, TEM, XPS, BET, UV-vis DRS, PL and photocurrents. The photocatalytic activity was evaluated by degradation of TC. The results showed that the hybrid-structure and plasma effect can effectively cause the multi-transfer of electrons and increase the separation rate of electron and hole pairs which obtained high photocatalytic activity. The photocatalytic degradation processes reveal that $^{\bullet}O_2{^-}$ and $h^+$ are major active species.

Synthesis of Antioxidant and Evaluation of Its Oxidation Stability for Biodiesel

  • Park, Soo-Youl;Shin, Seung-Rim;Shin, Joung-II;An, Kyoung-Lyong;Jun, Kun
    • Tribology and Lubricants
    • /
    • v.29 no.6
    • /
    • pp.392-396
    • /
    • 2013
  • Biodiesel fuels contain unsaturated fatty acid ester, which can easily oxidize, especially when exposed to ultraviolet light. The products formed by this oxidation give rise to sediment or gum formation. As a result, the fuel can contribute to the corrosion and plugging of the filter pump. Antioxidants have been used in an effort to stabilize biodiesels, but there is still a need for a biodiesel composition with improved oxidation stability. In general, good fuel compositions should provide synergistic combinations of a biodiesel and antioxidants. Our work involved the synthesis of antioxidants to improve the oxidative stability of biodiesel fuel.

Research on the development of green chemistry technology assessment techniques: a material reutilization case

  • Hong, Seokpyo;Ahn, Kilsoo;Kim, Sungjune;Gong, Sungyong
    • Environmental Analysis Health and Toxicology
    • /
    • v.30 no.sup
    • /
    • pp.2.1-2.11
    • /
    • 2015
  • Objectives This study presents a methodology that enables a quantitative assessment of green chemistry technologies. Methods The study carries out a quantitative evaluation of a particular case of material reutilization by calculating the level of "greenness" i.e., the level of compliance with the principles of green chemistry that was achieved by implementing a green chemistry technology. Results The results indicate that the greenness level was enhanced by 42% compared to the pre-improvement level, thus demonstrating the economic feasibility of green chemistry. Conclusions The assessment technique established in this study will serve as a useful reference for setting the direction of industry-level and government-level technological R&D and for evaluating newly developed technologies, which can greatly contribute toward gaining a competitive advantage in the global market.

Review : Present Status of Green Chemistry (녹색화학 기술동향)

  • Lee, Jun-Wung
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.14 no.2
    • /
    • pp.246-263
    • /
    • 2011
  • Mankind has just begun to recognize that the most crucial factor to achieve the sustainable society in the future is green technology. Most countries support the development of green technology to prevent catastrophes from global warming, mainly in the areas of reducing carbon dioxide from the atmosphere. However, most products we consume in everyday life are produced through chemical processes, and we often oversee the fact that the huge amount of waste and energy during these chemical processes will seriously influence our goal to achieve our future society sustainable. Thus the technologies to minimize the amount of disposed waste and energy consumption during chemical processes may be more important than to reduce the greenhouse gases. In this regard this review introduces the recent status of green chemistry and future prospects in order to help our chemists and engineers establish research projects based on the green chemistry principles.

The Emergence of Green Chemistry: Triple-Helix for Environmental Science in United States (녹색화학의 출현: 미국 환경과학의 삼중나선)

  • Jeon, June
    • Journal of Science and Technology Studies
    • /
    • v.13 no.1
    • /
    • pp.111-143
    • /
    • 2013
  • Green chemistry is a new scientific field which focuses on the design, manufacture, and use of chemical processes that could prevent pollution and at the same time improve yield efficiency. The few who have written on the emergence of green chemistry have not shed light on the political and economic motivations of green chemistry. As a new study of the emergence of green chemistry, this paper focuses on the relationship among the triple helix of academia, industry, and government which has been critical in the emergence of green chemistry. This paper argues that academia, industry and government created a common ground during the emergence of green chemistry under the common goal of sustainable development since its creation in 1991. Green chemists produced the knowledge to improve the synthetic efficiency to prevent pollution, and the chemical industry used green chemistry research to increase the economic profitability of production system. This specific form of alliance was supported and maintained amid a changing national environmental policy toward pollution prevention and a self-regulatory framework.

  • PDF

Acid-Base Bifunctional Metal-Organic Frameworks: Green Synthesis and Application in One-Pot Glucose to 5-HMF Conversion

  • Zhang, Yunlei;Jin, Pei;Meng, Minjia;Gao, Lin;Liu, Meng;Yan, Yongsheng
    • Nano
    • /
    • v.13 no.11
    • /
    • pp.1850132.1-1850132.14
    • /
    • 2018
  • The direct synthesis of metal-organic frameworks (MOFs) with acidic and basic active sites is challenging due to the introduction of functional groups by post-functionalization method often jeopardize the framework integrity. Herein, we report the direct synthesis of acid-base bifunctional MOFs with tuning acid-base strength. Employing modulated hydrothermal (MHT) approach, microporous MOFs named $UiO-66-NH_2$ was prepared. Through the ring-opening reaction of 1,3-propanesultone with amino group, $UiO-66-NH_2-SO_3H-type$ catalysts can be obtained. The synthesized catalysts were well characterized and their catalytic performances were evaluated in one-pot glucose to 5-HMF conversion. Results revealed the acid-base bi-functional catalyst possessed high activity and excellent stability. This work provides a general and economically viable approach for the large-scale synthesis of acid-base bi-functional MOFs for their potential use in catalysis field.