• Title/Summary/Keyword: alkali extraction

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Structure Optimization of Di-ionizable Calixarene Nano-baskets for Competitive Solvent Extraction of Alkali and Alkaline Earth Metals

  • Mokhtari, Bahram;Pourabdollah, Kobra
    • Bulletin of the Korean Chemical Society
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    • v.32 no.11
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    • pp.3855-3860
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    • 2011
  • The competitive solvent extractions of alkali and alkaline earth metals by di-ionizable calix[4]arene nano-baskets were studied using nine conformers of calix[4]arene nano-baskets. The objective of this work is to assess the variation of macrocycle conformation, orientation and position of pendant moieties upon the extraction parameters (efficiency, selectivity and $pH_{1/2}$) of the complexes. The results revealed that alternation of ring conformation in calixarene scaffold affects the solvent extraction parameters towards alkali and alkaline earth metals, while changing the orientation of pendant moieties from ortho- to para- as well as cis- to trans-analogues depicted no changes in those extraction parameters.

Quantitative Variation of Alkali-soluble Extracts from Coniferous Barks for Tannin-based Adhesives (타닌접착제를 위한 침엽수 수피의 알칼리성 추출물의 양적 변이)

  • Cho, Nam-Seok;Kim, Young-Sin;Han, Gyu-Seong
    • Journal of the Korean Wood Science and Technology
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    • v.25 no.1
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    • pp.23-27
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    • 1997
  • Alkali-soluble extracts were prepared from barks of Japanese larch(Larix leptolepis). Siberian larch(Larix gmelineii) and Radiata pine(Pinus radiata) The effect of various factors, such as particle size, liquor ratio, extraction temperature, and reaction time, on the extracts yield was investigated. Particle sizes affected the alkali-soluble extracts; the finer the particle size, the higher extracts and extract efficiency. High temperature and high liquor ratio were more effective. In the range of 0.25% to 1% NaOH concentration, alkali extracts were increased with the increasing alkali concentration. However, extract yields were leveled off above 0.5% alkali concentration. Extractions with NaHCO3 were almost equivalent to those of NaOH extraction. 1% NaOH and 1% NaHCO3 resulted in the highest yields of alkaline extracts. Extracts from Japanese larch were lower than those from Siberian larch and Radiata pine barks. Siberian larch bark was the best raw material for tannin adhesives, because its extractive yield was higher than those of the other barks. Concerning pH of alkaline media during extraction, small increases of the extract yields were resulted at range of pH 7 to pH 9, while a large increases from pH 9.0 to pH 12. This phenomenon is attributed to higher alkalinity.

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Inclusion Extraction of Alkali Metals by Emulsion Liquid Membranes and Nano-baskets of p-tert-Calix[4]arene Bearing Di-[N-(X)sulfonyl Carboxamide] and Di-(1-propoxy) in ortho-cone Conformation

  • Mokhtari, Bahram;Pourabdollah, Kobra
    • Bulletin of the Korean Chemical Society
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    • v.33 no.5
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    • pp.1509-1516
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    • 2012
  • Nano-assisted inclusion separation of alkali metals from basic solutions was reported by inclusion-facilitated emulsion liquid membrane process. The novelty of this study is application of nano-baskets of calixarene in the selective and efficient separation of alkali metals as both the carrier and the surfactant. For this aim, four derivatives of $p-tert-calix$[4]arene bearing different sulfonamide moieties were synthesized and their inclusion-extraction parameters were optimized including the calixarene scaffold $\mathbf{3}$ (4 wt %) as the carrier/demulsifier, the commercial kerosene as diluent in membrane, sulphonic acid (0.2 M) and ammonium carbonate (0.4 M) as the strip and the feed phases, the phase and the treat ratios of 0.8 and 0.3, mixing speed (300 rpm), and initial solute concentration (100 mg/L). The selectivity of membrane over more than ten interfering cations was examined and the results reveled that under the optimized operating condition, the degree of inclusion-extraction of alkali metals was as high as 98-99%.

Pre-extraction of Hemicelluloses from Korean Mixed Hardwood Chips Using Hot Water and Alkali Solution and its Characteristics (열수 및 알칼리 용액을 이용한 국산 목재 칩으로부터 헤미셀룰로오스의 선추출 및 특성 구명)

  • Cho, Hwi;Shin, Hee-Nae;Sim, Kyu-Jeong;Youn, Hye-Jung;Lee, Hak-Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.1
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    • pp.83-91
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    • 2011
  • Hemicelluloses are useful materials for papermaking and other biotechnological applications. To recover and further utilize the hemicelluloses, this study carried out the pre-extraction of the hemicelluloses from Korean mixed hardwoods chips using hot water and sodium hydroxide solution at various temperature and time conditions. Through the hot water pre-extraction, the wood components of 22% was extracted and the 35% of the hemicelluloses which were contained in the original wood chips were dissolved into the pre-extractives. The yield of the pre-extractives was more significantly influenced by the pre-extraction temperature than the time. The pre-extractives with the yield of 30% could be obtained by alkali pre-extraction and alkali concentration was the most important factor. It had lower hemicellulose content but high molecular weight, compared with the hot water pre-extractives.

Competitive Solvent Extraction of the Mixture of Alkali Metal and Alkaline Earth Metal Cation containing Crown Ether Carboxylic Acid and Crown Ether Phosphonic Acid (크라운에테르 카르복시산과 크라운에테르 포스포닉산을 포함한 알칼리 금속과 알칼리 토금속 양이온 혼합물의 경쟁적 용매추출)

  • Chung, Yeong-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.22 no.3
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    • pp.219-227
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    • 2005
  • Competitive solvent extraction of the mixure of alkali metal and alkaline earth cation from water into organic solvent containing the crown ether carboxylic acid and anlogous crown ether phosphonic acid was investigated as follows. The lipophilic group is found to strongly influence to the selective extraction in the mixed systems from only alkali metal cation for sym-(n-decyldibenzo)-16-crown-5-oxyacetic acid $\underline{1}$ to mostly alkaline earth metal cation for sym-bis[4(5)-tert-butylbenzo]-16-crown-5-oxyacetic acid $\underline{3}$. Monoethyl sym-(n-decyldibenzo)-16-crown-5-oxymethylphosphonic acid $\underline{2}$. and monoethyl-sym- bis]4(5)-tert-butylbenzo]-16-crown-5-oxymethylphosphonic acid $\underline{4}$ showed good selectivity for $Na^+$ over $Mg^{2+}$, the second extracted ion. Structural variation in the crown ether phosphonic acid somewhat was influenced to the extraction selectivity in the mixed systems. when variation of the ionized group is influenced in the mixed systems, the selectivity of $Na^+$ as the second extracted ion was much better crown ether carboxylic acid $\underline{1}$ than crown ether phosphonic acid $\underline{2}$, while the efficiency of $Na^+$ extraction was better $\underline{2}$ (83% total loading) than $\underline{1}$ (32%).

Techno-functional and rheological properties of Tenebrio molitor larvae protein by different extraction methods

  • Yeeun Kan;Insang Cho;Eunyoung Oh;Ra-Yeong Choi;Jeewon Koh;Yookyung Kim
    • International Journal of Industrial Entomology and Biomaterials
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    • v.48 no.2
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    • pp.86-97
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    • 2024
  • Alkaline- or salt-assisted extractions have been widely used to extract edible insect proteins, however, there is a need for extraction techniques that balance cost-efficient production as well as preserving the protein properties. Mealworm proteins (Tenebrio molitor larvae) were extracted using three different extraction methods-alkali (AMP), salt (SMP), and water (WMP)-and then physicochemical and techno-functional properties were examined. AMP had high yield, protein, and amino acid contents, whereas WMP had high moisture, ash, and fat contents. SDS-PAGE showed a wide range of molecular weights in WMP whereas mostly low molecular weights were observed in AMP and SMP. AMP had poor protein solubilities compared to SMP and WMP across all pHs. AMP had enhanced water-holding capacity and emulsion stability, whereas WMP had improved oil-holding capacity and foaming properties. WMP formed a gel with and without the transglutaminase. The physicochemical and techno-functional properties demonstrated that water-soluble mealworm protein was superior to alkali-and salt-soluble mealworm proteins. Considering the cost efficiency and minimal impact on the environment as well, a cold press juicer could be utilized for mass production of mealworm protein compared to the conventional methods of protein extraction using alkali and salt.

Solvent Extractions of Alkali Metal Cations and Alkaline Earth Cations by Ionizable Crown Ether Phosphonic Acids (이온성 크라운에테르 포스포닉산에 의한 알칼리 금속 양이온과 알칼리 토금속 양이온의 용매추출)

  • Chung, Yeong-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.22 no.1
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    • pp.50-55
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    • 2005
  • A comparison of alkali metal cation and alkaline earth cation solvent extraction was made for three additional monoionizable crown ethers and one diionizable crown ether. sym-(n-Octyldibenzo)-16-crown-5-oxyacetic acid $\underline{1}$ exhibited high efficiency and selecvity in solvent extraction of alkali metal cations with respect to that observed with alkaline earth cations. Sizes of $Na^+$ and $Ca^{2+}$ appropriately match with the cavity size of monoethyl sym-bis[4(5)-tert-butylbenzo]-16-crown-5-oxymethylphosphonic acid $\underline{3}$. As the result, $Na^+$ and $Ca^{2+}$ are the best extracted. sym-(n-Octyldibenzo)-16-crown-5-oxymethyldiphosphonic acid $\underline{4}$was found to be somewhat selective for $Na^+$ over $Li^+$ and other alkaline earth metal cations. In the complexation of alklaine earth cations by crown ether diphosphonic acid $\underline{4}$, $Ca^{2+}$ and $Sr^{2+}$ are the appropriate sizes, but lager $Ba^{2+}$ may be due to favorable formation of a sandwich type complex between the crown ether cavity and the dianion of the deprotonated crown ether phoaphonic acid moiety.

Non-chlorine Bleaching of Oak Kraft Pulp by Ozone (오존을 이용한 신갈나무 크라프트펄프의 무염소표백)

  • 김동호;백기현
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.29 no.2
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    • pp.36-45
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    • 1997
  • Newly bleaching sequence using oxygen, ozone and hydrogen peroxide has introduced to avoid pollution hazards from chlorinated organic compounds, because chlorine dioxide substitution bleaching was produced a little chlorinated organic substance. Oxygen-type chemicals replaced for chlorine has attracted much research attention. Bleachability of ozone was improved at low temperature and high pulp consistency. In third bleaching followed OZ bleaching, addition of O2 and NaBH4 in alkali extraction was effective than only alkali extraction. Bleachability of pulps in ozone bleaching(Z) was improved at higher consistency and lower temperature The addition O2 and NaBH4 in alkali extraction after OZ bleaching sequence improved brightness, when compared to those obtained by only alkaline extraction. Pulps bleached by ECF bleaching sequences such as OZEoD and OZEopD was obtained by 90% ISO brightness. The brightness of pulp bleached by TCF sequences with the ozone dosage of 1.6% was approached to target brightness (88~90%ISO). Pulps bleached Z stage combined bleaching sequence was reduced the viscosity to a little greater extent. However, physical properties of pulps was not great different compared to those bleached by conventional bleaching sequences. A pollution index of bleaching effluente by ozone combined bleaching sequences was lower than by conventional bleaching sequence, but somewhat higher than multistage bleaching sequences combined C/D stage.

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Extraction of Alkali Metal Cation with Crown Ethers and HDEHP (Crown Ether와 HDEHP에 의한 알칼리금속이온의 추출)

  • Ihn Chong Lee;Si Joong Kim;Chul Lee
    • Journal of the Korean Chemical Society
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    • v.30 no.4
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    • pp.359-368
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    • 1986
  • Solvent extraction equilibria of alkali metal cation with crown ether (DC18C6, DC24C8) and HDEHP have been studied. The extraction equilibrium constants increase in the order of, in the DC18C6 system, $Na^+, and in the DC24C8 system, $Rb^+. The species extracted to organic phase are $M_1(crown ether)_1\;(HDEHP)_1$. The magnitude of extraction equilibrium constant is determined by the distribution ratio of crown ether between organic and aqueous phase, and stability constant of crown ether-alkali metal complex.

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Comparison of Alginic Acid Yields and Viscosity by Different Extraction Conditions from Various Seaweeds (Laminaria religiosa, Hizikia fusiforme, and Undaria pinnatifida) (추출조건에 따른 해조류의 알긴산 수율과 점도)

  • 윤미옥;이승철;임종환;김정목
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.4
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    • pp.747-752
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    • 2004
  • Alginates were extracted from the Laminaria religiosa, Undaria pinnatifida, and Hizikia fusiforme by using four different extraction methods and compared the yields of alginate. Acid-alkali soluble alginate (AASA) extraction method from Undaria pinnatifida resulted in the best yield of alginate among the seaweeds. The optimal condition for extracting alginate from Laminaria religiosa was 0.4 N H$_2$SO$_4$ and 3% NaCO$_3$ concentrations at the AASA extraction method. The alginate yields of hot water extractable material (HWEM) water soluble alginate (WSA), alkali soluble alginate (ASA) and AASA in Hizikia fusiforme were 18.6, 4.7, 22.5 and 26.5%, respectively. The alginates manufactured by the WSA extraction method showed more bright color than those of the ASA and AASA extraction methods. The alginate prepared by the ASA extraction method from Hizikia fusiforme showed the higher viscosity than that of the ASA extraction method. The molecular weight of the alginate from Hizikia fusiforme was 33.3 kDa to 121.6 kDa depending on the extraction method.