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Ren, Jun,Song, Kai-he,Li, Zhenhuan,Wang, Qiang,Li, Jun,Wang, Yingxiong,Li, Debao,Kim, Chan Kyung Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.456 No.-
<P><B>Abstract</B></P> <P>The first principle calculations with on-site Coulomb repulsion U terms were carried out to investigate the 5-hydroxymethylfurfural (HMF) adsorption on the CuO(1 1 1) and Co<SUB>3</SUB>O<SUB>4</SUB>(1 1 0) surfaces, two widely used oxidation catalysts. The adsorption of HMF molecule is energetically favoured in both cases, and HMF is more inclined to bridge adsorption via hydroxyl and formyl groups binding with surface O and metal sites. Moreover, the adsorption energy relies on both the coordination type of surface lattice oxygen to which the H atom binds and the formation of H-bond involving hydroxyl and formyl groups on the adsorbed HMF. Also, the hydroxyl OH bond breaking is very easy and is likely to be the first step in HMF oxidation, and then the OH insertion reaction to produce 2,5-furandicarboxylic acid (FDCA). The corresponding experimental results also show that the CuO and Co<SUB>3</SUB>O<SUB>4</SUB> surfaces are promising candidate catalysts.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CuO(1 1 1) and Co<SUB>3</SUB>O<SUB>4</SUB>(1 1 0) surfaces catalyze the oxidation of 5-hydroxymethylfurfural (HMF). </LI> <LI> Initial binding was formed through bridged-adsorption with O atoms in HMF. </LI> <LI> Oxidation reaction proceeds through the OH bond breaking pathway. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Schematic potential energy diagram for the formyl CH and hydroxyl OH bonds of HMF dissociation on CuO(1 1 1) and Co<SUB>3</SUB>O<SUB>4</SUB>(1 1 0) surfaces. Obviously, the hydroxyl OH bond breaking is easier than that of the formyl CH bond on the two surfaces, which indicates the first step of oxidation of HMF to FDCA should be hydroxyl OH bond breaking.</P> <P>[DISPLAY OMISSION]</P>
Kinetics of 5-Hydroxymethylfurfural Formation in Chinese Acacia Honey during Heat Treatment
Yuyu Zhang,Yi Song,Tingting Zhou,Xiaojun Liao,Xiaosong Hu,Quanhong Li 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.6
In this paper, the 5-hydroxymethylfurfural (HMF) contents of the acacia honeys after heat treatment were determined by HPLC; the kinetics of HMF formation was also investigated. The HMF content of acacia honey was 0.38±0.01mg/kg, but rapidly increased to the maximum of 18,320.07±14.29 mg/kg at 190oC and decreased to 1,180.24±6.54 mg/kg at 230oC after heating. The HMF content increased gradually in honey samples heated in 12h at the temperature of 80, 100, and 120oC. The apparent frequency constant was kf =3.91×1025/h, and the apparent activation energy was Ea=173.10 kJ/mol. The HMF content in the acacia honey was related to honey composition,heating temperature, and time, and the HMF formation could also be related to the initial honey pH.
바이오매스 유래 플랫폼 케미컬들에 대한 효과적인 합성 방법들
이르샤드모비나 ( Mobina Irshad ),이성우 ( Seongwoo Lee ),최은주 ( Eunju Choi ),김정원 ( Jung Won Kim ) 한국공업화학회 2019 공업화학 Vol.30 No.3
5-Hydroxymethylfurfural (HMF) 및 그 유도체들인 2,5-furandicarboxylic acid (FDCA)와 2,5-diformylfuran (DFF)는 넓은 응용 범위와 중요한 화학 물질 생산을 위한 좋은 대체 자원으로 인해 “잠자는 거인”으로 인식되고 있다. 본 미니-리뷰 논문은 과거부터 최근까지 이러한 바이오매스 유래 케미컬 플랫폼들에 대한 합성, 전환과 적용에 관해 간략히 소개한다. 많은 과학적 노력들이 자연 환경과 새로운 미래 세대를 보호하기 위해서 재생 가능한 재료들의 최대한 활용을 위한 자연친화적-적용가능한 방법들을 찾기 위한 노력이 지속적으로 행해지고 있다. 최선의 해결책 중 하나는 자연 바이오매스로부터 플랫폼 케미컬을 개발하고 활용하는 것이다. 5-hydroxymethylfurfural (HMF) and its derivatives, 2,5-furandicarboxylic acid (FDCA) or 2,5-diformylfuran (DFF), are regarded as the “sleeping giants” owing to their wide range of applications and a good alternative source for the production of significant chemicals in almost all kind of industries. This mini-review briefly covers the aspects related to the syntheses, transformation, and applications for the biomass-derived platform chemicals from past to most recent. Many scientific efforts have continuously been made to find out the environmental benign applicable ways in order to achieve the full advantage of these renewable materials because of not only to protect the globe but also shield the future of new generations. One of the best solutions could be the development and utilization of platform chemicals from the natural biomass.
Eun-Sil Kang,채다원,Baekjin Kim,김영규 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.1
2,5-Dihydroxymethylfuran (DHMF) and 5-hydroxymethylfuranoic acid (HMFA) are the versatile intermediate chemicals of high industrial potential. An efficient preparation of both DHMF and HMFA is reported from biomass-derived HMF via a Cannizzaro reaction using ionic liquids as a reusable reaction solvent under the water-free conditions. The operationally simple and environment-friendly process produces both DHMF and HMFA from HMF consistently in good to high yields up to five runs with the recycled ionic liquid.
조남석(Nam-Seok Cho),조대행(Dae Haeng Cho),김용환(Yong Hwan Kim),신수정(Soo-Jeong Shin) 한국펄프·종이공학회 2010 한국펄프·종이공학회 학술발표논문집 Vol.2010 No.10
We investigated acid hydrolysis characteristics of yellow poplar woodmeal with concentrated sulfuric acid for high concentration of monosaccharides production. Woodmeal to 72% sulfuric acid ratio (w/v), 2<SUP>nd</SUP> hydrolysis temperature and time were main variables for finding optimum reaction condition. Optimum woodmeal to 72% sulfuric acid ratio was 1:1.6(w/v) and 2<SUP>nd</SUP> hydrolysis temperature and time was 105℃ and 40 min as 44.8 g/L of glucose and 25.2 g/L of xylose in hydrolysis solution. In this acid hydrolysis solution, furfural, 5-HMF, low molecular weight phenolic compounds were identified. Furfural and 5-HMF concentration were increased as increasing 2<SUP>nd</SUP> hydrolysis time. More than 40 min of 2<SUP>nd</SUP> hydrolysis at 110℃, xylose concentration was decreased but glucose concentration was leveled out because xylose to furfural reaction was faster than xylan to xylose, but cellulose to glucose reaction was similar rate with glucose to 5-HMF at that 2<SUP>nd</SUP> hydrolysis reaction condition.
Characteristics of Sucrose Thermal Degradation with High Temperature and High Pressure Treatment
Koan Sik Woo,In Guk Hwang,Youn Ri Lee,Junsoo Lee,Heon Sang Jeong 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.3
Thermal degradation characteristics of sucrose was investigated. A 20% sucrose solution was heated to temperatures of 110-150℃ for 1-5 hr. Chromaticity, pH, organic acids, 5-hydroxymethylfurfural (HMF), free sugars, electron donating ability (EDA), and ascorbic acid equivalent antioxidant capacity (AEAC) of the heated sucrose solutions were evaluated. With increasing temperatures and times, the L-, a-, and b-values decreased; however, total color difference (ΔEab) increased. The pH and sucrose contents decreased, and fructose and glucose contents increased with increasing heating temperature and time. Organic acids, such as formic acid, lactic acid, and levulinic acid, and HMF contents increased with increasing heating temperatures and times. EDA (%) and the AEAC of the heated sucrose solutions increased with increasing heating temperature and time. The heated sucrose solution was more effective than unheated sucrose solution, having higher EDA (90 fold), and AEAC (13 fold).
Characteristics of the Thermal Degradation of Glucose and Maltose Solutions
우관식,김현영,황인국,이상훈,정헌상 한국식품영양과학회 2015 Preventive Nutrition and Food Science Vol.20 No.2
In order to investigate the thermal degradation of glucose and maltose solutions after high temperature and high pressure (HTHP) treatment, the samples were treated at temperatures of 110, 120, 130, 140, and 150ºC for 1, 2, 3, 4, and 5 h in an apparatus for HTHP treatment. Glucose and maltose solutions (20% w/w) were prepared by weighing glucose and maltose and adding distilled water in the desired proportion. Chromaticity, pH, organic acids, 5-hydroxymethylfurfural (HMF), free sugar contents, electron donating ability (EDA), and ascorbic acid equivalent antioxidant capacity (AEAC) were evaluated. With increasing heating temperatures and times, the L-, a-, and b-values decreased. The pH and free sugar contents decreased, and organic acids and HMF contents increased with greater temperatures and times. EDA (%) and the AEAC of the heating sugars increased with the increases in temperatures and times.