JPS6146040B2 - - Google Patents
Info
- Publication number
- JPS6146040B2 JPS6146040B2 JP3587881A JP3587881A JPS6146040B2 JP S6146040 B2 JPS6146040 B2 JP S6146040B2 JP 3587881 A JP3587881 A JP 3587881A JP 3587881 A JP3587881 A JP 3587881A JP S6146040 B2 JPS6146040 B2 JP S6146040B2
- Authority
- JP
- Japan
- Prior art keywords
- cottonseed oil
- crude cottonseed
- membrane
- organic solvent
- crude
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 239000012528 membrane Substances 0.000 claims description 58
- 235000012343 cottonseed oil Nutrition 0.000 claims description 46
- 239000002385 cottonseed oil Substances 0.000 claims description 45
- 239000004642 Polyimide Substances 0.000 claims description 20
- 229920001721 polyimide Polymers 0.000 claims description 20
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical group CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 claims description 18
- 238000000034 method Methods 0.000 claims description 17
- 239000003960 organic solvent Substances 0.000 claims description 17
- 229920000642 polymer Polymers 0.000 claims description 17
- 238000005194 fractionation Methods 0.000 claims description 9
- 239000003921 oil Substances 0.000 claims description 7
- 235000019198 oils Nutrition 0.000 claims description 7
- 238000007865 diluting Methods 0.000 claims description 5
- -1 fatty acid ester Chemical class 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 3
- 235000014113 dietary fatty acids Nutrition 0.000 claims description 2
- 229930195729 fatty acid Natural products 0.000 claims description 2
- 239000000194 fatty acid Substances 0.000 claims description 2
- 229930195733 hydrocarbon Natural products 0.000 claims description 2
- 125000005647 linker group Chemical group 0.000 claims description 2
- 125000000962 organic group Chemical group 0.000 claims description 2
- 239000004215 Carbon black (E152) Substances 0.000 claims 1
- RXKJFZQQPQGTFL-UHFFFAOYSA-N dihydroxyacetone Chemical compound OCC(=O)CO RXKJFZQQPQGTFL-UHFFFAOYSA-N 0.000 claims 1
- 150000002430 hydrocarbons Chemical group 0.000 claims 1
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 12
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 10
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 8
- 239000007788 liquid Substances 0.000 description 8
- 239000000243 solution Substances 0.000 description 8
- 239000003795 chemical substances by application Substances 0.000 description 7
- 239000012466 permeate Substances 0.000 description 7
- 239000002904 solvent Substances 0.000 description 7
- 230000008961 swelling Effects 0.000 description 7
- ZWEHNKRNPOVVGH-UHFFFAOYSA-N 2-Butanone Chemical compound CCC(C)=O ZWEHNKRNPOVVGH-UHFFFAOYSA-N 0.000 description 6
- MTHSVFCYNBDYFN-UHFFFAOYSA-N diethylene glycol Chemical compound OCCOCCO MTHSVFCYNBDYFN-UHFFFAOYSA-N 0.000 description 6
- 238000004042 decolorization Methods 0.000 description 5
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 5
- 239000012535 impurity Substances 0.000 description 5
- 229920001223 polyethylene glycol Polymers 0.000 description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 4
- SECXISVLQFMRJM-UHFFFAOYSA-N N-Methylpyrrolidone Chemical compound CN1CCCC1=O SECXISVLQFMRJM-UHFFFAOYSA-N 0.000 description 4
- QBKSWRVVCFFDOT-UHFFFAOYSA-N gossypol Chemical compound CC(C)C1=C(O)C(O)=C(C=O)C2=C(O)C(C=3C(O)=C4C(C=O)=C(O)C(O)=C(C4=CC=3C)C(C)C)=C(C)C=C21 QBKSWRVVCFFDOT-UHFFFAOYSA-N 0.000 description 4
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 4
- 239000000049 pigment Substances 0.000 description 4
- 238000000108 ultra-filtration Methods 0.000 description 4
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 description 3
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 3
- 239000002202 Polyethylene glycol Substances 0.000 description 3
- 230000001112 coagulating effect Effects 0.000 description 3
- 239000010779 crude oil Substances 0.000 description 3
- 230000007717 exclusion Effects 0.000 description 3
- DMEGYFMYUHOHGS-UHFFFAOYSA-N heptamethylene Natural products C1CCCCCC1 DMEGYFMYUHOHGS-UHFFFAOYSA-N 0.000 description 3
- 229910052739 hydrogen Inorganic materials 0.000 description 3
- 239000001257 hydrogen Substances 0.000 description 3
- 125000004435 hydrogen atom Chemical class [H]* 0.000 description 3
- SBASXUCJHJRPEV-UHFFFAOYSA-N 2-(2-methoxyethoxy)ethanol Chemical compound COCCOCCO SBASXUCJHJRPEV-UHFFFAOYSA-N 0.000 description 2
- RGSFGYAAUTVSQA-UHFFFAOYSA-N Cyclopentane Chemical compound C1CCCC1 RGSFGYAAUTVSQA-UHFFFAOYSA-N 0.000 description 2
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 description 2
- XTHFKEDIFFGKHM-UHFFFAOYSA-N Dimethoxyethane Chemical compound COCCOC XTHFKEDIFFGKHM-UHFFFAOYSA-N 0.000 description 2
- IAZDPXIOMUYVGZ-UHFFFAOYSA-N Dimethylsulphoxide Chemical compound CS(C)=O IAZDPXIOMUYVGZ-UHFFFAOYSA-N 0.000 description 2
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 2
- OFBQJSOFQDEBGM-UHFFFAOYSA-N Pentane Chemical compound CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 2
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical compound C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 description 2
- QHOPXUFELLHKAS-UHFFFAOYSA-N Thespesin Natural products CC(C)c1c(O)c(O)c2C(O)Oc3c(c(C)cc1c23)-c1c2OC(O)c3c(O)c(O)c(C(C)C)c(cc1C)c23 QHOPXUFELLHKAS-UHFFFAOYSA-N 0.000 description 2
- 239000003463 adsorbent Substances 0.000 description 2
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 description 2
- JHIVVAPYMSGYDF-UHFFFAOYSA-N cyclohexanone Chemical compound O=C1CCCCC1 JHIVVAPYMSGYDF-UHFFFAOYSA-N 0.000 description 2
- 239000000975 dye Substances 0.000 description 2
- 239000000796 flavoring agent Substances 0.000 description 2
- 235000019634 flavors Nutrition 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 229930000755 gossypol Natural products 0.000 description 2
- 229950005277 gossypol Drugs 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 150000003949 imides Chemical group 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- TZIHFWKZFHZASV-UHFFFAOYSA-N methyl formate Chemical compound COC=O TZIHFWKZFHZASV-UHFFFAOYSA-N 0.000 description 2
- FDPIMTJIUBPUKL-UHFFFAOYSA-N pentan-3-one Chemical compound CCC(=O)CC FDPIMTJIUBPUKL-UHFFFAOYSA-N 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 239000011550 stock solution Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- AVQQQNCBBIEMEU-UHFFFAOYSA-N 1,1,3,3-tetramethylurea Chemical compound CN(C)C(=O)N(C)C AVQQQNCBBIEMEU-UHFFFAOYSA-N 0.000 description 1
- RYHBNJHYFVUHQT-UHFFFAOYSA-N 1,4-Dioxane Chemical compound C1COCCO1 RYHBNJHYFVUHQT-UHFFFAOYSA-N 0.000 description 1
- ZFPGARUNNKGOBB-UHFFFAOYSA-N 1-Ethyl-2-pyrrolidinone Chemical compound CCN1CCCC1=O ZFPGARUNNKGOBB-UHFFFAOYSA-N 0.000 description 1
- GGYVTHJIUNGKFZ-UHFFFAOYSA-N 1-methylpiperidin-2-one Chemical compound CN1CCCCC1=O GGYVTHJIUNGKFZ-UHFFFAOYSA-N 0.000 description 1
- ZNQVEEAIQZEUHB-UHFFFAOYSA-N 2-ethoxyethanol Chemical compound CCOCCO ZNQVEEAIQZEUHB-UHFFFAOYSA-N 0.000 description 1
- DKPFZGUDAPQIHT-UHFFFAOYSA-N Butyl acetate Natural products CCCCOC(C)=O DKPFZGUDAPQIHT-UHFFFAOYSA-N 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- LVZWSLJZHVFIQJ-UHFFFAOYSA-N Cyclopropane Chemical compound C1CC1 LVZWSLJZHVFIQJ-UHFFFAOYSA-N 0.000 description 1
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- XBDQKXXYIPTUBI-UHFFFAOYSA-M Propionate Chemical compound CCC([O-])=O XBDQKXXYIPTUBI-UHFFFAOYSA-M 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 238000004061 bleaching Methods 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000000701 coagulant Substances 0.000 description 1
- 238000004737 colorimetric analysis Methods 0.000 description 1
- 238000004332 deodorization Methods 0.000 description 1
- 230000006866 deterioration Effects 0.000 description 1
- SBZXBUIDTXKZTM-UHFFFAOYSA-N diglyme Chemical compound COCCOCCOC SBZXBUIDTXKZTM-UHFFFAOYSA-N 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 239000008157 edible vegetable oil Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000002170 ethers Chemical class 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- WBJINCZRORDGAQ-UHFFFAOYSA-N formic acid ethyl ester Natural products CCOC=O WBJINCZRORDGAQ-UHFFFAOYSA-N 0.000 description 1
- FUZZWVXGSFPDMH-UHFFFAOYSA-M hexanoate Chemical compound CCCCCC([O-])=O FUZZWVXGSFPDMH-UHFFFAOYSA-M 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 150000003904 phospholipids Chemical class 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000012465 retentate Substances 0.000 description 1
- 238000001223 reverse osmosis Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- HXJUTPCZVOIRIF-UHFFFAOYSA-N sulfolane Chemical compound O=S1(=O)CCCC1 HXJUTPCZVOIRIF-UHFFFAOYSA-N 0.000 description 1
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- ZIBGPFATKBEMQZ-UHFFFAOYSA-N triethylene glycol Chemical compound OCCOCCOCCO ZIBGPFATKBEMQZ-UHFFFAOYSA-N 0.000 description 1
- JLGLQAWTXXGVEM-UHFFFAOYSA-N triethylene glycol monomethyl ether Chemical compound COCCOCCOCCO JLGLQAWTXXGVEM-UHFFFAOYSA-N 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
Description
本発明は粗製綿実油の脱色方法に関するもので
ある。
綿実油の製造プロセスは、綿実原料の圧搾・抽
出により得られた粗製油を脱ガム、脱酸、脱臭の
各工程により精製するものである。これらの各工
程のうちで最も重要なものは脱色工程であるが、
これは粗製綿実油中に有毒なゴシポール等の不純
物色素が多量に含まれているため、食用油として
供するためにはどうしても除かなければならない
からである。
また脱色工程において淡色な脱色油が得られな
ければ、他の工程をいかに改良しても淡色で風味
のよい精製油が得られないのである。
従来、粗製綿実油の脱色方法は、活性白上類等
の吸着剤を加えて減圧下に加熱し冷却後過する
方法が広く用いられている。しかし、添加した吸
着剤の廃棄物が公害源となつたり、加熱・減圧操
作に多くのエネルギーを必要としたり、また、加
熱による油中成分の変質が生じやすいという欠点
があつた。
本発明の目的は、粗製綿実油の脱色において上
述のような欠点を改良して、公害防止、経済性等
の点においてすぐれた脱色法を提供し、以つて淡
色で風味がよく且つ有毒色素を実質的に含有しな
い綿実油を得ることにある。
本発明者らは上記の如き従来欠点を改良するた
め種々研究を重ねた結果、粗製綿実油の精製にお
いて、不純物色素を含む該粗製油を有機溶剤で希
釈し、これを加圧下にポリイミド系重合体よりな
る半透膜と接触させることにより、大きい透過液
量にて顕著な脱色効果による脱色油が得られるこ
とを見出し、本発明に至つたものである。
即ち、本発明は、粗製綿実油を有機溶剤で希釈
した後、実質的に一般式
（但し、R1は２価の有機基を示す。）
で表わされるポリイミド重合体よりなり、かつ
2000以上10000未満の分子量分画性を有する半透
膜と加圧下に接触させることにより、色度を90％
以上排除した脱色油を得ることを特徴とする粗製
綿実油の脱色方法に関するものである。
本発明において用いるに適する上記ポリイミド
重合体からなる半透膜は、本発明者らの出願に係
る特開昭55−152507号及び特願昭55−42682号明
細書（特開昭56−139104号公報参照）に詳細に説
明されているが、本発明においては、上記一般式
においてR1が一般式
（但し、Ｘは２価の結合基を示す。）
で表わされるポリイミド重合体からなる半透膜が
好ましく用いられる。ここに、Ｘの具体例として
は−CH2−，−Ｃ（CH3）2−，−Ｏ−，−SO2−、等
を挙げることができるが、特に高い温度に加熱さ
れた粗製綿実油と接触しても、長期間にわたつて
その分子量分画性が変化しない−CH2−や−Ｏ−
が好ましい。
本発明においては、
イミド環の数／イミド環の数＋アミド酸結合の数×10
0
で定義されるイミド化率が約70％以上であるポリ
イミド重合体を用いることができるが、好適には
イミド化率90％以上であり、特に好適には98〜
100℃であるものを用いる。また、本発明におい
て用いられるポリイミド重合体としては、その極
限粘度（30℃での測定値）が通常0.55〜1.00、好
ましくは0.60〜0.85であり、平均分子量は20000
〜120000、好ましくは30000〜80000である。
前記一般式で表わされるポリイミド重合体から
なる限外過膜、逆浸透膜等の異方性構造を有す
る半透膜の製造方法は、特開昭54−71785号や特
開昭54−94477号に開示されているが、本発明に
おいては、特開昭55−152507号明細書に記載され
ているように、特に、前記ポリイミド重合体と一
般式
R3O−〔CH2CHR2O〕−oR4
（但し、R2，R3及びR4はそれぞれ独立に水
素、メチル基又はエチル基を示し、ｎはR2が水
素のとき１〜５の整数を示し、R2がメチル基又
はエチル基のとき１〜３の整数を示す。）
で表わされる膨潤剤とを水等の凝固溶剤に相溶性
を有する有機溶剤（以下、ドープ溶剤という。）
に溶解してドープを調整し、このドープを適宜の
支持基材に塗布した後、上記ポリイミド重合体を
溶解せず、且つ、上記ドープ溶剤と相溶性を有す
ると共に膨潤剤を溶解する凝固溶剤中に浸漬し、
上記ポリイミド重合体を凝固、膜化して得られる
半透膜が好ましく用いられる。
上記膨潤剤において、ｎはR2が水素のとき、
好ましくは２又は３の整数であり、R2がメチル
基又はエチル基のとき、好ましくは１又は２の整
数であり、従つて、具体例としてはエチレングリ
コール、ジエチレングリコール、トリエチレング
リコール、エチレングリコールモノメチルエーテ
ル、エチレングリコールモノエチルエーテル、エ
チレングリコールジメチルエーテル、ジエチレン
グリコールモノメチルエーテル、ジエチレングリ
コールジメチルエーテル、トリエチレングリコー
ルモノメチルエーテル等の（ポリ）エチレングリ
コール及びそのメチル又はエチル誘導体を挙げる
ことができる。また、ドープ溶剤としてはＮ−メ
チル−２−ピロリドン、Ｎ−エチル−２−ピロリ
ドン、Ｎ−メチル−２−ピペリドン、ジメチルホ
ルムアミド、ジメチルアセトアミド、ジメチルス
ルホキシド、テトラメチル尿素、スルホラン等を
例示することができる。
また、本発明においては、特願昭55−42682号
明細書（特開昭56−139104号公報参照）に記載さ
れているように、前記ポリイミド重合体とテトラ
ヒドロフラン、ジオキサン、アセトン、メチルエ
チルケトン、ジエチルケトン、シクロヘキサノ
ン、ギ酸メチル及びギ酸エチルから選ばれる少な
くとも一種の液状極性有機化合物である膨潤剤と
をドープ溶剤に溶解して作成したドープより製膜
して得られる半透膜も用いることができる。
更に、凝固溶剤としては一般に水が用いられる
が、ドープ溶剤と相溶性を有し、膨潤剤を溶解す
る一方、上記ポリイミド重合体を凝固させる溶剤
であればよく、例えばメタノール、エタノール、
アセトン、エチレングリコール、ジエチレングリ
コール、ジエチレングリコールモノメチルエーテ
ル等の一種以上と水との混合溶剤や、或いはこれ
らを単独で凝固剤として用いることもできる。
尚、ポリイミド重合体と膨潤剤とを溶解したド
ープから限外過膜を製造する方法は前記公開公
報及び特願昭55−42682（特開昭56−139104号公
報参照）に記載されているので、詳細は省略する
が、前記一般式で表わされるポリエチレングリコ
ール及びそのエーテル誘導体及びその他の膨潤剤
の使用量は、ポリイミド重合体100重量部当り30
〜300重量部、好ましくは50〜200重量部であり、
ドープ中のポリイミド重合体濃度は５〜30重量％
が適当である。
本発明において用いるポリイミド重合体からな
る半透膜は、2000以上10000未満の分子量分画性
を有する半透膜がよい。分子量分画性の値が小さ
すぎると透過速度が小さくなる傾向があり、一
方、大きすぎると脱色性能に劣る傾向があるから
である。ここに分子量分画性は、分子量が既知の
溶質に対する半透膜の排除率を測定することによ
つて知ることができる。実際には、例えば平均分
子量が既知であり、分子量分布が単分散性のポリ
エチレングリコールを溶質（濃度5000ppm）と
するトルエン溶液を用いて膜の排除率を測定する
のがよい。従つて、ここにおいても、25℃の温度
で３Kg／cm2の圧力下に平均分子量が種々異なるポ
リエチレングリコールのトルエン溶液を用いて排
除率を測定し、排除率が少なくとも95％であるポ
リエチレングリコールの最小の分子量をその膜の
分子量分画性とする。
本発明において、粗製綿実油を希釈する有機溶
剤は、上記したポリイミド半透膜を溶解しないこ
とを要し、分子量は綿実油より小さいのがよく、
通常50〜200、好ましくは60〜150である。具体的
にはペンタン、ヘキサン、ヘプタン、オクタン等
の脂肪族炭化水素、シクロプロパン、シクロペン
タン、シクロヘキサン、シクロヘプタン等の脂環
族炭化水素、ベンゼン、トルエン、キシレン等の
芳香族炭化水素、アセトン、メチルエチルケトン
等の脂肪族ケトン類、酢酸エチル、酢酸ブチル等
の低級脂肪酸エステル等の一種又は二種以上の混
合物が用いられるが、好ましくはヘキサンのよう
な脂肪族炭化水素が用いられる。
粗製綿実油をこれら有機溶剤で希釈した溶液で
あるミセラは、通常、綿実油を10〜80重量％、好
ましくは20〜50重量％含有するのがよいが、しか
し、これに限定されるものではない。
次に、本発明においては、粗製綿実油のミセ
ラ、即ち有機溶剤の溶液は一般的には５℃以上80
℃以下であつて、用いる有機溶剤の蒸発が著しく
ない範囲の温度で半透膜に加圧下に接触される
が、好ましくは10〜60℃の範囲である。一般に処
理温度が高い程、大きい透過液量を得ることがで
きる。尚、本発明においては、高い温度で膜処理
を行なつても、半透膜はその分子量分画性を実質
的に一定に保つので、膜透過液として著しく脱色
された淡色の粗製綿実油溶液が得られる。５℃よ
り低い温度では透過液量が実用上からは小さく、
80℃よりも高い温度では実質的に半透膜がその分
子量分画性を保ち得ることが難しい。また、粗製
綿実油ミセラは膜処理に当つては、用いる半透膜
の形態によつて0.1〜50Kg／cm2（ゲージ圧、以下
同じ。）の圧力に加圧されて半透膜に接触され
る。例えば内径が0.1〜２mm程度の毛細管状半透
膜を用いる場合には0.1〜５Kg／cm2、好ましくは
0.3〜３Kg／cm2の圧力に、また、内径が２〜50mm
程度の管状半透膜の場合には２〜50Kg／cm2、好ま
しくは５〜20Kg／cm2の圧力に加圧される。このよ
うに圧力は膜の形態にもよるが、一般には小さす
ぎると綿実油の透過速度が小さく、一方、圧力が
大きすぎると膜が圧密化したり、又は損傷するお
それがあるので好ましくない。
更に、本発明においては、上記のような条件下
で、精製綿実油が膜透過液として粗製綿実油の少
なくとも50％、好ましくは66〜98％が回収される
まで、粗製綿実油ミセラを半透膜に連続して循環
させつつ、加圧接触させるのが望ましい。必要な
らばミセラに有機溶剤を適宜加え、透過した分を
補なう。粗製綿実油ミセラの膜面に対する流速は
膜面に平行の線速を0.1〜８ｍ／秒、好ましくは
0.5〜３ｍ／秒とするのがよい。例えば管状に形
成された半透膜に粗製綿実油ミセラをポンプ等に
より連続して循環させるのであるが、粗製綿実油
ミセラの膜面に平行な線速が小さすぎるときは、
膜面での不純物色素等の不透過成分の濃度分極が
大きくなつて、綿実油の透過を妨げ、また、大き
すぎるときは徒らにポンプのエネルギー効率を低
くするので好ましくない。
本発明の方法は、脱色された綿実油を得るもの
であるが、また不純物色素答を、必要に応じて膜
不透過液から適宜回収することもできる。通常は
膜不透過液を再びヘキサン等の有機溶剤で希釈
し、膜処理した後、膜不透過液から有機溶剤を除
去することにより高純度の色素を得ることができ
る。
本発明の方法によれば、以上のようにゴシポー
ル等の不純物色素を含有する粗製綿実油を有機溶
剤で希釈し、これを特定のポリイミド重合体から
なる半透膜にて単に一段の膜処理を行つて、膜透
過液を得、この膜透過液より有機溶剤を除去して
色度を90％以上排除した淡色で風味のよい脱色綿
実油を得ることができ、膜処理前又は後の付加的
な精製工程を省略しても、製品として十分に高純
度の精製綿実油を得ることができるのである。
更に、本発明の方法によれば、粗製綿実油中に
含まれるリン脂質等のガム質も膜によつて排除さ
れ、特に高い温度も必要としないため、綿実油中
の成分の変質も抑制されて、非常に高品質の綿実
油を得ることができる。
以下本発明を実施例により具体的に説明する。
参考例
前記一般式においてR1が
The present invention relates to a method for decolorizing crude cottonseed oil. The cottonseed oil manufacturing process involves refining crude oil obtained by pressing and extracting cottonseed raw materials through the steps of degumming, deacidification, and deodorization. The most important of these steps is the decolorization step,
This is because crude cottonseed oil contains a large amount of impurity pigments such as toxic gossypol, which must be removed in order to use it as edible oil. Furthermore, unless a light-colored bleached oil is obtained in the decolorization process, a light-colored refined oil with good flavor cannot be obtained no matter how much other steps are improved. Conventionally, a widely used method for decolorizing crude cottonseed oil is to add an adsorbent such as activated white oil, heat it under reduced pressure, cool it, and then filter it. However, there are disadvantages in that the waste of the adsorbent added becomes a source of pollution, a lot of energy is required for heating and depressurizing operations, and the components in the oil tend to change in quality due to heating. The purpose of the present invention is to improve the above-mentioned drawbacks in the decolorization of crude cottonseed oil, and to provide a decolorization method that is excellent in terms of pollution prevention, economic efficiency, etc. The purpose of the present invention is to obtain cottonseed oil that does not contain any harmful substances. The present inventors have conducted various studies in order to improve the conventional drawbacks as described above, and as a result, in refining crude cottonseed oil, the crude oil containing impurity pigments is diluted with an organic solvent, and then the crude oil is diluted with a polyimide polymer under pressure. The inventors have discovered that a bleached oil with a remarkable bleaching effect can be obtained with a large amount of permeated liquid by contacting with a semipermeable membrane made of the following, and this has led to the present invention. That is, in the present invention, after diluting crude cottonseed oil with an organic solvent, substantially the general formula (However, R 1 represents a divalent organic group.) Consisting of a polyimide polymer represented by
By contacting under pressure with a semipermeable membrane with a molecular weight fractionation of 2000 or more and less than 10000, the chromaticity can be reduced to 90%.
The present invention relates to a method for decolorizing crude cottonseed oil, which is characterized by obtaining the decolorized oil excluded above. A semipermeable membrane made of the above-mentioned polyimide polymer suitable for use in the present invention is described in JP-A-55-152507 and Japanese Patent Application No. 55-42682 (JP-A-56-139104) filed by the present inventors. (Refer to the official publication), but in the present invention, R 1 in the above general formula is (However, X represents a divalent bonding group.) A semipermeable membrane made of a polyimide polymer represented by the following is preferably used. Here , specific examples of -CH 2 - and -O-
is preferred. In the present invention, the number of imide rings/the number of imide rings + the number of amic acid bonds x 10
It is possible to use a polyimide polymer having an imidization rate of about 70% or more as defined by 0, preferably an imidization rate of 90% or more, and particularly preferably an imidization rate of 98 to
Use one that has a temperature of 100℃. Furthermore, the polyimide polymer used in the present invention has an intrinsic viscosity (measured value at 30°C) of usually 0.55 to 1.00, preferably 0.60 to 0.85, and an average molecular weight of 20,000.
~120000, preferably 30000~80000. Methods for producing semipermeable membranes having an anisotropic structure, such as ultrafiltration membranes and reverse osmosis membranes made of polyimide polymers represented by the above general formula, are described in JP-A-54-71785 and JP-A-54-94477. However, in the present invention, as described in JP - A-55-152507, in particular, the polyimide polymer and the general formula R3O- [ CH2CHR2O ]- o R 4 (However, R 2 , R 3 and R 4 each independently represent hydrogen, a methyl group or an ethyl group, n represents an integer of 1 to 5 when R 2 is hydrogen, and R 2 is a methyl group or An organic solvent (hereinafter referred to as a dope solvent) that is compatible with a coagulating solvent such as water and a swelling agent (indicates an integer of 1 to 3 when the ethyl group is an ethyl group).
After preparing a dope by dissolving it in immersed in
A semipermeable membrane obtained by coagulating and forming a membrane from the above polyimide polymer is preferably used. In the above swelling agent, when R 2 is hydrogen, n is
It is preferably an integer of 2 or 3, and when R 2 is a methyl group or an ethyl group, it is preferably an integer of 1 or 2. Therefore, specific examples include ethylene glycol, diethylene glycol, triethylene glycol, and ethylene glycol monomethyl. (Poly)ethylene glycol and its methyl or ethyl derivatives such as ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, and triethylene glycol monomethyl ether can be mentioned. Examples of dope solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methyl-2-piperidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide, tetramethylurea, and sulfolane. can. In addition, in the present invention, as described in Japanese Patent Application No. 55-42682 (see Japanese Patent Application Laid-Open No. 56-139104), the polyimide polymer and tetrahydrofuran, dioxane, acetone, methyl ethyl ketone, diethyl ketone, etc. A semipermeable membrane obtained by forming a membrane from a dope prepared by dissolving a swelling agent, which is at least one liquid polar organic compound selected from , cyclohexanone, methyl formate, and ethyl formate, in a dope solvent can also be used. Furthermore, water is generally used as a coagulating solvent, but any solvent that is compatible with the dope solvent, dissolves the swelling agent, and coagulates the polyimide polymer may be used, such as methanol, ethanol,
A mixed solvent of water and one or more of acetone, ethylene glycol, diethylene glycol, diethylene glycol monomethyl ether, etc., or these alone can be used as a coagulant. Incidentally, the method for producing an ultrafiltration membrane from a dope in which a polyimide polymer and a swelling agent are dissolved is described in the above-mentioned publication and Japanese Patent Application No. 55-42682 (see Japanese Patent Application Laid-Open No. 56-139104). Although details are omitted, the amount of polyethylene glycol represented by the above general formula, its ether derivative, and other swelling agents used is 30 parts by weight per 100 parts by weight of the polyimide polymer.
~300 parts by weight, preferably 50-200 parts by weight,
Polyimide polymer concentration in dope is 5-30% by weight
is appropriate. The semipermeable membrane made of polyimide polymer used in the present invention preferably has a molecular weight fractionation of 2,000 or more and less than 10,000. This is because if the molecular weight fractionation value is too small, the permeation rate tends to be low, while if it is too large, the decolorization performance tends to be poor. The molecular weight fractionation property can be determined by measuring the exclusion rate of a semipermeable membrane for a solute of known molecular weight. In practice, for example, it is preferable to measure the rejection rate of a membrane using a toluene solution containing polyethylene glycol as a solute (concentration 5000 ppm) whose average molecular weight is known and whose molecular weight distribution is monodisperse. Therefore, here too, the rejection rate was measured using toluene solutions of polyethylene glycols with different average molecular weights under a pressure of 3 Kg/cm 2 at a temperature of 25°C, and the rejection rate was determined using toluene solutions of polyethylene glycol with a rejection rate of at least 95%. The minimum molecular weight is taken as the molecular weight fractionation property of the membrane. In the present invention, the organic solvent for diluting the crude cottonseed oil must not dissolve the polyimide semipermeable membrane described above, and preferably has a molecular weight smaller than that of cottonseed oil.
Usually 50-200, preferably 60-150. Specifically, aliphatic hydrocarbons such as pentane, hexane, heptane, and octane, alicyclic hydrocarbons such as cyclopropane, cyclopentane, cyclohexane, and cycloheptane, aromatic hydrocarbons such as benzene, toluene, and xylene, acetone, One or a mixture of two or more of aliphatic ketones such as methyl ethyl ketone and lower fatty acid esters such as ethyl acetate and butyl acetate are used, and preferably an aliphatic hydrocarbon such as hexane is used. Micella, which is a solution of crude cottonseed oil diluted with these organic solvents, usually contains cottonseed oil in an amount of 10 to 80% by weight, preferably 20 to 50% by weight, but is not limited thereto. Next, in the present invention, the miscella of crude cottonseed oil, that is, the solution of organic solvent is generally heated to 80°C or above 5°C.
The semipermeable membrane is contacted under pressure at a temperature below 0.degree. C. at which the organic solvent used does not significantly evaporate, preferably in the range of 10 to 60.degree. Generally, the higher the treatment temperature, the greater the amount of permeate that can be obtained. In the present invention, even if the membrane treatment is performed at high temperatures, the semipermeable membrane maintains its molecular weight fractionation property substantially constant, so that the membrane permeate is a light-colored crude cottonseed oil solution that has been significantly decolored. can get. At temperatures lower than 5℃, the amount of permeated liquid is small for practical purposes.
At temperatures higher than 80°C, it is substantially difficult for a semipermeable membrane to maintain its molecular weight fractionation. In addition, during membrane treatment, crude cottonseed oil miscella is brought into contact with a semipermeable membrane under pressure of 0.1 to 50 kg/cm 2 (gauge pressure, the same applies hereinafter) depending on the form of the semipermeable membrane used. . For example, when using a capillary semipermeable membrane with an inner diameter of about 0.1 to 2 mm, the pressure is 0.1 to 5 Kg/cm 2 , preferably
Pressure of 0.3~3Kg/ cm2 and inner diameter of 2~50mm
In the case of a tubular semipermeable membrane of about 100 lbs., it is pressurized to a pressure of 2 to 50 kg/cm 2 , preferably 5 to 20 kg/cm 2 . As described above, the pressure depends on the form of the membrane, but in general, if the pressure is too low, the permeation rate of cottonseed oil will be low, while if the pressure is too high, the membrane may become compacted or damaged, so it is not preferable. Further, in the present invention, the crude cottonseed oil miscella is continuously passed through the semi-permeable membrane under the conditions described above until at least 50%, preferably 66-98%, of the crude cottonseed oil is recovered as the membrane permeate. It is desirable to pressurize the contact while circulating the mixture. If necessary, add an appropriate amount of organic solvent to the miscella to compensate for the permeation. The flow velocity of the crude cottonseed oil miscella to the membrane surface is a linear velocity parallel to the membrane surface of 0.1 to 8 m/sec, preferably
The speed is preferably 0.5 to 3 m/sec. For example, crude cottonseed oil micella is continuously circulated through a tubular semipermeable membrane using a pump or the like, but if the linear velocity parallel to the membrane surface of the crude cottonseed oil micella is too low,
The concentration polarization of non-permeable components such as impurity pigments on the membrane surface becomes large, impeding the permeation of cottonseed oil, and if it is too large, it undesirably lowers the energy efficiency of the pump. Although the method of the present invention is to obtain decolorized cottonseed oil, impurity dyes can also be appropriately recovered from the membrane retentate if necessary. Usually, a highly pure dye can be obtained by diluting the membrane non-permeable liquid again with an organic solvent such as hexane, performing membrane treatment, and then removing the organic solvent from the membrane non-permeable liquid. According to the method of the present invention, as described above, crude cottonseed oil containing impurity pigments such as gossypol is diluted with an organic solvent, and then subjected to a single membrane treatment using a semipermeable membrane made of a specific polyimide polymer. Then, a membrane permeate is obtained, and by removing the organic solvent from this membrane permeate, it is possible to obtain a light-colored and flavorful decolorized cottonseed oil with chromaticity eliminated by more than 90%, and additional purification before or after membrane treatment. Even if this step is omitted, refined cottonseed oil of sufficiently high purity can be obtained as a product. Furthermore, according to the method of the present invention, gummy substances such as phospholipids contained in the crude cottonseed oil are also removed by the membrane, and no particularly high temperature is required, so deterioration of the components in the cottonseed oil is also suppressed. Very high quality cottonseed oil can be obtained. The present invention will be specifically explained below using examples. Reference example In the above general formula, R 1 is
【式】であり、イミド化率
が99％以上、極限粘度〔η〕が0.58のポリイミド
26重量％を含むＮ−メチル−２−ピロリドン溶液
に、ポリイミド100重量部当たりアセトン120重量
部を膨潤剤として添加して均一なドープを調整
し、このドープをガラス管の内面に流延塗布し、
30rpmで回転させつつ、水平に保持して、管内に
50／分（０℃、１気圧換算）の流量にて管一端
から30秒、次に他端からまた30秒送風し、蒸発処
理を行なつた。この処理後、直ちにこのガラス管
を５℃の水中に投入して５時間浸漬し、内径12
mm、膜厚200μの管状限外過膜を得た。この限
外過膜を内径12.5mmの穿孔ステンレス管に装着
した後、エタノール中に浸漬して膜から水を抜い
た。この膜モジユールを粗製綿実油ミセラの通液
ラインに接続し、膜処理を行なつた。尚、この膜
は6000の分子量分画性を有する。
色度の測定はロピボンド比色法を使用し、ミセ
ラ原液及び膜透過液の色度を比較した。比較に当
つては、一般に行なわれているように、
色度＝｛〔黄色（Ｙ）の値〕＋10×〔赤色（Ｒ）
の値〕＋
10×〔青色（Ｂ）の値〕｝
×１／（セルの長さ）
の式から各々の色度を求めた（セルの長さは１イ
ンチを基準とした）。
実施例
30％の粗製綿実油を含有するヘキサンミセラを
圧力５Kg／cm2、流速14／分、温度40℃で膜Ｂの
モジユールに循環通液した後、ヘキサンを留去し
て脱色綿実油を得た。ミセラ原液及び膜透過液の
色度を測定した。その結果を下記第１表に示す。
膜で一段処理することにより色度排除率は97％に
も達し、得られた脱色綿実油は実用上十分淡色
で、且つ、風味も良いものであつた。Polyimide with [formula], imidization rate of 99% or more, and intrinsic viscosity [η] of 0.58
A uniform dope was prepared by adding 120 parts by weight of acetone per 100 parts by weight of polyimide as a swelling agent to an N-methyl-2-pyrrolidone solution containing 26% by weight, and this dope was cast onto the inner surface of a glass tube. ,
While rotating at 30 rpm, hold it horizontally and insert it into the pipe.
The evaporation process was carried out by blowing air at a flow rate of 50/min (0° C., 1 atm) from one end of the tube for 30 seconds and then from the other end for another 30 seconds. After this treatment, the glass tube was immediately placed in water at 5°C and soaked for 5 hours.
A tubular ultrafiltration membrane with a thickness of 200 μm and a thickness of 200 μm was obtained. This ultrafiltration membrane was attached to a perforated stainless steel tube with an inner diameter of 12.5 mm, and then immersed in ethanol to remove water from the membrane. This membrane module was connected to the liquid passage line of the crude cottonseed oil micella, and membrane treatment was performed. This membrane has a molecular weight fractionation of 6000. The chromaticity was measured using the Ropibond colorimetric method, and the chromaticity of the micellar stock solution and the membrane-permeated liquid were compared. For comparison, as is generally done, chromaticity = {[yellow (Y) value] + 10 x [red (R) value] + 10 x [blue (B) value]} x 1 The chromaticity of each was determined from the formula: /(cell length) (cell length was based on 1 inch). Example Hexane miscella containing 30% crude cottonseed oil was circulated through the module of membrane B at a pressure of 5 kg/cm 2 , a flow rate of 14/min, and a temperature of 40°C, and then the hexane was distilled off to obtain decolorized cottonseed oil. . The chromaticity of the micellar stock solution and the membrane permeate was measured. The results are shown in Table 1 below.
By performing one-step treatment with the membrane, the color exclusion rate reached 97%, and the decolorized cottonseed oil obtained was sufficiently light in color for practical use and had a good flavor.
【表】【table】
【表】
第１表において色度の排除率は下記式より算出
した値である。
排除率（％）＝100×｛１−膜透過液色度／原液ミセ
ラ色度｝[Table] In Table 1, the chromaticity exclusion rate is a value calculated from the following formula. Rejection rate (%) = 100 × {1-membrane permeate liquid chromaticity/undiluted solution micellar chromaticity}
Claims (1)
に一般式 （R1は２価の有機基を示す。） で表されるポリイミド系重合体よりなり、かつ
2000以上10000未満の分子量分画性を有する半透
膜と加圧下に接触させることにより、色度を90％
以上排除した脱色油を得ることを特徴とする粗製
綿実油の脱色方法。 ２ R1が一般式 （Ｘは２価の結合基を示す。） で表されることを特徴とする特許請求の範囲第１
項記載の粗製綿実油の脱色方法。 ３ Ｘが−CH2−又は−Ｏ−であることを特徴と
する特許請求の範囲第２項記載の粗製綿実油の脱
色方法。 ４ 有機溶剤が分子量50〜200の炭化水素、低級
脂肪酸エステル、脂肪族ケトン又はこれらの混合
物であることを特徴とする特許請求の範囲第１項
記載の粗製綿実油の脱色方法。 ５ 有機溶剤がヘキサンであることを特徴とする
特許請求の範囲第４項記載の粗製綿実油の脱色方
法。 ６ 粗製綿実油の有機溶剤溶液を10〜60℃の温度
で半透膜に接触させることを特徴とする特許請求
の範囲第１項記載の粗製綿実油の脱色方法。 ７ 粗製綿実油含量が10〜80重量％となるように
有機溶剤で希釈することを特徴とする特許請求の
範囲第１項記載の粗製綿実油の脱色方法。[Claims] 1. After diluting crude cottonseed oil with an organic solvent, substantially the general formula (R 1 represents a divalent organic group.) Consisting of a polyimide polymer represented by
By contacting under pressure with a semipermeable membrane with a molecular weight fractionation of 2000 or more and less than 10000, the chromaticity can be reduced to 90%.
A method for decolorizing crude cottonseed oil, which is characterized by obtaining decolorized oil free of the above. 2 R 1 is a general formula (X represents a divalent bonding group)
Method for decolorizing crude cottonseed oil as described in Section 1. 3. The method for decolorizing crude cottonseed oil according to claim 2, wherein X is -CH2- or -O-. 4. The method for decolorizing crude cottonseed oil according to claim 1, wherein the organic solvent is a hydrocarbon having a molecular weight of 50 to 200, a lower fatty acid ester, an aliphatic ketone, or a mixture thereof. 5. The method for decolorizing crude cottonseed oil according to claim 4, wherein the organic solvent is hexane. 6. The method for decolorizing crude cottonseed oil according to claim 1, characterized in that a solution of the crude cottonseed oil in an organic solvent is brought into contact with a semipermeable membrane at a temperature of 10 to 60°C. 7. A method for decolorizing crude cottonseed oil according to claim 1, which comprises diluting the crude cottonseed oil with an organic solvent so that the content of the crude cottonseed oil becomes 10 to 80% by weight.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3587881A JPS57149399A (en) | 1981-03-11 | 1981-03-11 | Method of decoloring crude cottonseed oil |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3587881A JPS57149399A (en) | 1981-03-11 | 1981-03-11 | Method of decoloring crude cottonseed oil |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57149399A JPS57149399A (en) | 1982-09-14 |
| JPS6146040B2 true JPS6146040B2 (en) | 1986-10-11 |
Family
ID=12454253
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3587881A Granted JPS57149399A (en) | 1981-03-11 | 1981-03-11 | Method of decoloring crude cottonseed oil |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57149399A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4617126A (en) * | 1984-08-03 | 1986-10-14 | Uop Inc. | Membrane separation of hydrocarbons |
| JPH0816231B2 (en) * | 1985-02-01 | 1996-02-21 | 花王株式会社 | Separation method of fats and oils and fatty acids |
| US5395531A (en) * | 1992-09-28 | 1995-03-07 | Pall Corporation | Method for fractionating a fat composition |
| CA2855246A1 (en) * | 2011-11-09 | 2013-05-16 | Andrew Boam | Membrane-based processes for reducing at least one impurity and making a concentrate comprising at least one natural component from a non-marine fatty acid oil mixture, and compositions resulting thereof |
-
1981
- 1981-03-11 JP JP3587881A patent/JPS57149399A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57149399A (en) | 1982-09-14 |
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