Title

以溶劑萃取法回收應用在界面活性劑萃取程序的非離子界面活性劑的研究

Translated Titles

Study on Recovery of Nonionic Surfactants by Solvent Extraction after Surfactant-Based Extraction Processes

DOI

10.6844/NCKU.2011.02269

Authors

黃敏獅

Key Words

濁點萃取(CPE) ; L3相萃取 ; 多環芳香烴(PAHs) ; 非離子表面活性劑 ; 溶劑萃取 ; 烷烴 ; 醇 ; ASTM D2959 - 95 ; HPLC分析 ; cloud point extraction (CPE) ; L3-phase extraction ; polycyclic aromatic hydrocarbons (PAHs) ; nonionic surfactant ; solvent extraction ; alkane ; alcohol ; ASTM D2959-95 ; HPLC analysis

PublicationName

成功大學化學工程學系學位論文

Volume or Term/Year and Month of Publication

2011年

Academic Degree Category

碩士

Advisor

陳炳宏

Content Language

英文

Chinese Abstract

溶劑萃取法已成功地試圖解除9種多環芳香烴(PAHs)的化合物而且追還包含在富含表面活性劑之液相的非離子表面活性劑,Tergitol 15-S-7和Tergitol 15-S-5。以使這程序更經濟環保,這種追回是必要的。個別濃度的PAHs之測量是利用具備UV - Vis和螢光檢測器的HPLC。我們藉由標準測試方法ASTM D2959 – 95來表面活性劑濃度之測定。 在本研究,探討各種烷烴從共存之PAH溶質來分離各種表面活性劑。烷烴包括正辛烷,正癸烷,正十二烷,正十四烷及正十六烷。我們也採用各種醇類,如乙醇,正丙醇,異丙醇,正丁醇和異丁醇來降低系統的疏水性。通過引進這些溶劑,包含PA的富含表面活性劑之液相往往共存地相分離成兩個液相:上層有機之液相和下層親水性之液相。在溶劑萃取後,我們在下層親水性之液相沒有檢測到PAHs,而表面活性劑可能在兩個液相同時分佈。 在探討各種烷烴的研究中,因溶劑萃取後在上層有機之液相產生最大多環芳烴追回率,同時在下層親水性之液相保留更多的表面活性劑,採用正十二烷的效果視為最佳。在濁點萃取後(CPE) ,藉由這種溶劑和改變溶液重量比例,ca. 60-63%的表面活性劑可以從富含表面活性劑之液相追回。最佳條件為 1:1或1:0.75富含表面活性劑之液相/溶劑之重量比。在L3相萃取後,利用富含表面活性劑之液相/正十二烷的1:1重量比之加法,加用15 WT -%的正丙醇或異丙醇獲得56%載於富含表面活性劑之液相的TERGITOL 15 - S – 5之追回率。 關鍵字:濁點萃取(CPE),L3相萃取; 多環芳香烴(PAHs),非離子表面活性劑,溶劑萃取;烷烴,醇,ASTM D2959 - 95,HPLC分析

English Abstract

Solvent extraction method has been successfully attempted to remove 9 compounds of polycyclic aromatic hydrocarbons (PAHs) and to recover nonionic surfactant Tergitol 15-S-7 and Tergitol 15-S-5 contained in the surfactant-rich phase. This recovery is necessary to make the process more economical and environmental friendly. The HPLCs equipped with UV-Vis and Fluorescence detectors were used to determine individual concentration of PAHs. The surfactant concentration was measured according to the standard test method ASTM D2959-95. In this work, various alkanes have been employed to separate surfactants from coexisting PAH solutes. These alkanes include n-octane, n-decane, n-dodecane, n-tetradecane, and n-hexadecane. Various alcohols, such as ethanol, n-propanol, iso-propanol, n-butanol, and iso-butanol were also used to decrease the hydrophobicity of the system. With introduction of these solvents, the PAH-containing surfactant-rich phase tends to phase-separate into two coexisting phases: the upper organic phase and the lower hydrophilic phase. No PAHs was detected in the lower hydrophilic phase after solvent extraction, while the surfactant might be distributed in both phases. Among various alkanes used, n-dodecane worked the best since it produced the maximum PAHs recovery in the upper organic phase after solvent extraction, while retaining more surfactant in the lower hydrophilic phase. By using this solvent and several variations of weight ratio, ca. 60-63% of surfactant could be recovered from the surfactant-rich phase after a CPE. The optimal condition was 1:1 or 1:0.75 surfactant-rich phase/solvent weight ratios. Addition of n-dodecane in 1:1 weight ratio with surfactant-rich phase after L3-phase extraction, added with 15 wt-% of n-propanol or iso-propanol can recover 56% of Tergitol 15-S-5 contained in the surfactant-rich phase. Keywords: cloud point extraction (CPE); L3-phase extraction; polycyclic aromatic hydrocarbons (PAHs); nonionic surfactant; solvent extraction; alkane; alcohol; ASTM D2959-95; HPLC analysis

Topic Category 工學院 > 化學工程學系
工程學 > 化學工業
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