• Title/Summary/Keyword: 숙과

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Chemical Transformation of Succinic Acid by Using Amberlite IR-120 and the Reusability of Catalyst (Amberlite IR-120를 사용한 숙신산의 화학적 전환과 촉매의 재 사용성)

  • Lee, Byong-Wook;Kim, Hwang-Min;Kim, Young-Wun;Kim, Yeong-Joon
    • Journal of the Korean Chemical Society
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    • v.55 no.6
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    • pp.1007-1011
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    • 2011
  • Dioctyl succinates and succinic anhydride were synthesized from succinic acid in the presence of a cation exchange resin, Amberlite IR-120. The synthesis of dioctyl succinate from succinic acid and octanol was perfomed in 18 h reflux condition with Amberlite IR-120 and the isolated yield of product was over 90%. For the synthesis of succinic anhydride, succinic acid was refluxed in isopropenyl acetate for 18 h with Amberlite IR-120 as a catalyst. The long reaction time was significantly reduced to less than 10 min under microwave irradiation. The catalyst was reusable at least 4 times with keeping product yield of higher than 80%.

Extraction Equilibria of Succinic Acid by Using Aqueous Two Phases System Containing Imidazolium Ionic Liquids and Salts (이미다졸계 이온성액체와 염을 포함한 수상이성분계를 이용한 숙신산의 추출 평형)

  • Lee, Yong Hwa;Kang, Jeong Won;Hong, Yeon Ki;Kim, Ki-Sub
    • Clean Technology
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    • v.20 no.4
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    • pp.349-353
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    • 2014
  • Succinic acid is an important precursor in industries producing biopolymers, pharmaceutical and food additives and green solvents. However, due to the high price of petroleum and the global $CO_2$ emission, the biological production of succinic acid from renewable biomass is a novel process due to the fixation of $CO_2$ into succinate during fermentation. In this study, aqueous two phase systems based on imidazolium ionic liquids/$K_2HPO_4$ were used as an effective separation and concentration process for succinic acid. Experimental results show that aqueous two phase systems can be formed by adding appropriate amount of imidazolium ionic liquids to aqueous $K_2HPO_4$ solutions in the presence of succinic acid. It can be found that the ability of imidazolium ionic liquids for phase separation followed the order [HMIm][Br]${\fallingdotseq}$[OMIm][Br]>[BMIm][Br]>[EMIm][Br]. The maximum value of extraction efficiency for succinic acid was about 90% and the amount of coextracted water into top phase is proportional to the chain length of cation in imidazolium ionic liquids. It was concluded that the aqueous two phase systems composed of imidazolium ionic liquids/$K_2HPO_4$ was effective for the selective extraction and concentration of succinic acid.

Amylograph Pasting Properties of Flour and Starch of Korean Rices Differing in Maturity (숙기에 따른 우리나라 쌀가루와 전분의 아밀로그래프 호화성질)

  • Lee, Soo-Jeong;Kim, Sung-Kon
    • Applied Biological Chemistry
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    • v.41 no.6
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    • pp.421-425
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    • 1998
  • The amylograph pasting properties of flours $(9{\sim}12%,\;db)$ and starches $(7.5{\sim}9.0%\;db)$ of Korean rice cultivars indicated that the flour concentration to give a fixed peak viscosity was higher by 1.32 times compared with starch, regardless the maturity. Only at 12% flour concentration the peak viscosity and breakdown viscosity were differentiated among maturity groups, which suggested that flour may be better tool than starch in characterizing the maturity groups by pasting properties.

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