JPH0686406B2 - Method for producing acrylic ester - Google Patents
Method for producing acrylic esterInfo
- Publication number
- JPH0686406B2 JPH0686406B2 JP1100168A JP10016889A JPH0686406B2 JP H0686406 B2 JPH0686406 B2 JP H0686406B2 JP 1100168 A JP1100168 A JP 1100168A JP 10016889 A JP10016889 A JP 10016889A JP H0686406 B2 JPH0686406 B2 JP H0686406B2
- Authority
- JP
- Japan
- Prior art keywords
- acrylic acid
- liquid
- esterification
- reactor
- separation column
- 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 - Lifetime
Links
- -1 acrylic ester Chemical class 0.000 title claims description 14
- 238000004519 manufacturing process Methods 0.000 title claims description 11
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 claims description 84
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 claims description 84
- 238000005886 esterification reaction Methods 0.000 claims description 57
- 239000007788 liquid Substances 0.000 claims description 56
- 238000006243 chemical reaction Methods 0.000 claims description 45
- 238000000926 separation method Methods 0.000 claims description 37
- 230000032050 esterification Effects 0.000 claims description 34
- 239000000203 mixture Substances 0.000 claims description 25
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 22
- 239000003054 catalyst Substances 0.000 claims description 22
- NWUYHJFMYQTDRP-UHFFFAOYSA-N 1,2-bis(ethenyl)benzene;1-ethenyl-2-ethylbenzene;styrene Chemical compound C=CC1=CC=CC=C1.CCC1=CC=CC=C1C=C.C=CC1=CC=CC=C1C=C NWUYHJFMYQTDRP-UHFFFAOYSA-N 0.000 claims description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 11
- 239000003729 cation exchange resin Substances 0.000 claims description 10
- 239000007795 chemical reaction product Substances 0.000 claims description 10
- 239000002994 raw material Substances 0.000 claims description 8
- 125000005396 acrylic acid ester group Chemical group 0.000 claims description 7
- 230000002378 acidificating effect Effects 0.000 claims description 6
- DNIAPMSPPWPWGF-GSVOUGTGSA-N (R)-(-)-Propylene glycol Chemical compound C[C@@H](O)CO DNIAPMSPPWPWGF-GSVOUGTGSA-N 0.000 claims description 4
- 125000002723 alicyclic group Chemical group 0.000 claims description 4
- 125000004432 carbon atom Chemical group C* 0.000 claims description 3
- 239000011347 resin Substances 0.000 description 12
- 229920005989 resin Polymers 0.000 description 12
- 239000002253 acid Substances 0.000 description 8
- 150000002148 esters Chemical class 0.000 description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 6
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 6
- 230000007423 decrease Effects 0.000 description 6
- 238000000034 method Methods 0.000 description 6
- 239000012071 phase Substances 0.000 description 6
- 238000006116 polymerization reaction Methods 0.000 description 6
- 239000003112 inhibitor Substances 0.000 description 5
- 229910052500 inorganic mineral Inorganic materials 0.000 description 5
- 239000011707 mineral Substances 0.000 description 5
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical compound OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000009835 boiling Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- LAQYHRQFABOIFD-UHFFFAOYSA-N 2-methoxyhydroquinone Chemical compound COC1=CC(O)=CC=C1O LAQYHRQFABOIFD-UHFFFAOYSA-N 0.000 description 2
- NIXOWILDQLNWCW-UHFFFAOYSA-M Acrylate Chemical compound [O-]C(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-M 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 2
- QIGBRXMKCJKVMJ-UHFFFAOYSA-N Hydroquinone Chemical compound OC1=CC=C(O)C=C1 QIGBRXMKCJKVMJ-UHFFFAOYSA-N 0.000 description 2
- BAPJBEWLBFYGME-UHFFFAOYSA-N Methyl acrylate Chemical compound COC(=O)C=C BAPJBEWLBFYGME-UHFFFAOYSA-N 0.000 description 2
- 229910000147 aluminium phosphate Inorganic materials 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000003197 catalytic effect Effects 0.000 description 2
- 238000007796 conventional method Methods 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 229910001882 dioxygen Inorganic materials 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 230000008961 swelling Effects 0.000 description 2
- GEYOCULIXLDCMW-UHFFFAOYSA-N 1,2-phenylenediamine Chemical compound NC1=CC=CC=C1N GEYOCULIXLDCMW-UHFFFAOYSA-N 0.000 description 1
- WJFKNYWRSNBZNX-UHFFFAOYSA-N 10H-phenothiazine Chemical compound C1=CC=C2NC3=CC=CC=C3SC2=C1 WJFKNYWRSNBZNX-UHFFFAOYSA-N 0.000 description 1
- AVXURJPOCDRRFD-UHFFFAOYSA-N Hydroxylamine Chemical compound ON AVXURJPOCDRRFD-UHFFFAOYSA-N 0.000 description 1
- 229920002125 Sokalan® Polymers 0.000 description 1
- 239000008346 aqueous phase Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- CQEYYJKEWSMYFG-UHFFFAOYSA-N butyl acrylate Chemical compound CCCCOC(=O)C=C CQEYYJKEWSMYFG-UHFFFAOYSA-N 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012527 feed solution Substances 0.000 description 1
- 239000003456 ion exchange resin Substances 0.000 description 1
- 229920003303 ion-exchange polymer Polymers 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 229950000688 phenothiazine Drugs 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000010992 reflux Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000012607 strong cation exchange resin Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Landscapes
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明はアクリル酸エステルの製造方法に関する。更に
詳しく述べると、アクリル酸と、炭素数１〜４の低級脂
肪族アルコールまたは脂環式アルコールとをエステル化
反応させることからなるアクリル酸エステルの製造方法
に関する。TECHNICAL FIELD The present invention relates to a method for producing an acrylic ester. More specifically, the present invention relates to a method for producing an acrylate ester, which comprises subjecting acrylic acid to an esterification reaction of a lower aliphatic alcohol having 1 to 4 carbon atoms or an alicyclic alcohol.
［従来の技術］ 従来、アクリル酸エスルルを連続的に製造するに際し
て、アクリル酸とアルコールとを反応器にて硫酸，リン
酸等の鉱酸や強酸性陽イオン交換樹脂のエステル化触媒
を用いて反応させ、アクリル酸分離塔にて反応生成物を
蒸留して未反応のアクリル酸を主成分とする高沸点分と
生成アクリル酸エステル、未反応アルコールおよび生成
水を主成分とする低沸点分とに分離し、更に、前者から
はアクリル酸を適宜精製処理して反応原料とともに循環
再使用する一方、後者からはアクリル酸エステルを分離
・精製するとともに未反応アルコールを回収して反応器
へ循環する操作が行なわれている（特公昭63−20415
号、特開昭58−159442号各公報）。[Prior Art] Conventionally, in the continuous production of esluryl acrylate, acrylic acid and alcohol were used in a reactor with a mineral acid such as sulfuric acid or phosphoric acid or an esterification catalyst of a strongly acidic cation exchange resin. The reaction product is reacted and distilled in an acrylic acid separation column to distill the reaction product into a high-boiling-point component containing unreacted acrylic acid as a main component and a low-boiling-point component containing produced acrylic acid ester, unreacted alcohol and produced water as main components. The acrylic acid is purified from the former and recycled and reused together with the reaction raw material, while the acrylic ester is separated and purified from the latter and unreacted alcohol is recovered and recycled to the reactor. Operation is being carried out (Japanese Patent Publication No. 63-20415)
No. 58-159442).
硫酸，リン酸等の鉱酸をエステル化触媒として用いる方
法（特開昭58−26843号）では、触媒を連続的に反応器
に投入するため触媒の経時劣化がなく反応系内の状態を
一定に保つ利点があるが、腐食性の高い鉱酸を用いるの
で耐食性の機器材質を選定せざるをえず、機器が高価に
なると同時に、廃液中に含まれる鉱酸を無害化する廃液
処理も繁雑となる欠点を有する。In the method of using a mineral acid such as sulfuric acid or phosphoric acid as an esterification catalyst (Japanese Patent Laid-Open No. 58-26843), the catalyst is continuously charged into the reactor, so that there is no deterioration of the catalyst over time and the state of the reaction system is kept constant. However, since a highly corrosive mineral acid is used, it is necessary to select a corrosion-resistant equipment material, which makes the equipment expensive and waste liquid treatment that renders the mineral acid contained in the waste fluid harmless. It has the drawback that
一方、強酸性陽イオン交換樹脂をエステル化触媒として
用いる方法（特公昭63−20415号、特開昭58−159442号
公報）では上述の鉱酸をエステル化触媒として用いる方
法のような欠点は起こらない。しかし、エステル化触媒
として反応器に充填された強酸性陽イオン交換樹脂は長
期にわたって交換されることがなく、連続運転に伴って
経時的に樹脂の劣化が起こる。また、エステル化反応
後、反応生成物はアクリル酸分離塔にて蒸留するが、該
アクリル酸分離塔においては、高温になると重合物の生
成が顕著になったり急激な重合の危険が生じるので許容
できる塔低温度の上限を規定してこの規定温度以下に納
まるように完全にアクリル酸を分離せずにアクリル酸エ
ステルを含んだ状態で塔底液を抜き出し、適宜精製処理
して反応原料とともに循環再使用することが行なわれて
いる。ところが、従来方法によるエステル化反応におい
ては、通常、温度一定で反応が行われていたことから、
転化率の低下によって、アクリル酸エステル収量を確保
するためにはアクリル酸分離塔の塔底液中のアクリル酸
エステルの組成を低下させねばならず、アクリル酸分離
塔塔低温度が上昇してくる。その結果、重合物の生成物
が増えて収率低下し、ついには規定した温度に到達した
ところで運転を停止して触媒交換が行なわれる。更に
は、アクリル酸分離塔の塔底液は反応器に循環されるの
で塔底液組成が変化するのに伴って反応器入口での液組
成も変化し、樹脂が膨潤または収縮を起こし場合によっ
ては割れが起こったりし、このこともまた樹脂寿命を短
くする要因となっている。On the other hand, the method of using a strongly acidic cation exchange resin as an esterification catalyst (Japanese Patent Publication No. Sho 63-20415 and Japanese Patent Application Laid-Open No. 58-159442) does not have the drawbacks of the above-mentioned method of using a mineral acid as an esterification catalyst. Absent. However, the strong acid cation exchange resin filled in the reactor as an esterification catalyst is not exchanged for a long period of time, and the resin deteriorates over time with continuous operation. Further, after the esterification reaction, the reaction product is distilled in an acrylic acid separation column, but in the acrylic acid separation column, the formation of a polymer becomes remarkable at a high temperature and there is a risk of rapid polymerization. The upper limit of the tower low temperature that can be set is specified, and the tower bottom liquid is extracted in the state of containing acrylic acid ester without completely separating acrylic acid so that the temperature falls below this specified temperature, and is appropriately purified and circulated along with the reaction raw materials. It is being reused. However, in the esterification reaction by the conventional method, since the reaction was usually performed at a constant temperature,
Due to the decrease in conversion rate, in order to secure the yield of acrylic acid ester, the composition of acrylic acid ester in the bottom liquid of the acrylic acid separation column must be reduced, and the low temperature of the acrylic acid separation column tower rises. . As a result, the amount of polymer products increases and the yield decreases, and when the temperature reaches the specified temperature, the operation is stopped and the catalyst is replaced. Furthermore, since the bottom liquid of the acrylic acid separation column is circulated to the reactor, the liquid composition at the reactor inlet also changes as the bottom liquid composition changes, and the resin causes swelling or shrinking. Cracks occur, which is also a factor that shortens the life of the resin.
［発明が解決しようとする課題］ 本発明の目的はこのような従来法の欠点を改善すること
にある。即ち安価な機器材質を用い、廃液処理費用を削
減し、長時間の連続運転が可能になるように樹脂寿命を
維持するアクリル酸エスルテの製造方法を提供すること
にある。[Problems to be Solved by the Invention] An object of the present invention is to remedy the drawbacks of the conventional methods. That is, it is an object of the present invention to provide a method for producing esulte acrylate that uses inexpensive equipment materials, reduces waste liquid treatment costs, and maintains the resin life so that long-term continuous operation is possible.
［課題を解決するための手段］ 本発明者等は鋭意検討の結果、アクリル酸と炭素数１〜
４の低級脂肪族アルコールまたは脂環式アルコールを強
酸性陽イオン交換樹脂を触媒としてエステル化反応させ
る際に、、アクリル酸の転化率が常に一定になる様に反
応温度を調節しながらエステル化反応させることによっ
て、アクリル酸分離塔を安定した状態で運転でき、エス
テル化反応器に循環する循環液の組成が安定し、反応器
の入口液組成も安定し、前記本発明の目的を達成できる
ことを見出した。即ち本発明はアクリル酸と、炭素数１
〜４の低級脂肪族アルコールまたは脂環式アルコールと
をエステル化反応器に供給し、該反応器にて強酸性陽イ
オン交換樹脂を触媒としてアクリル酸の転化率が常に一
定になる様に反応温度を調節し、かつ上記アクリル酸お
よびアルコールのエステル化反応器に新規に供給する原
料液とアクリル酸分離塔からの循環液とからなるエステ
ル化反応器への供給液の組成を常に実質的に一定になる
ようにしてエステル化反応をさせ、得られた反応生成物
をアクリル酸分離塔に導いて、アクリル酸分離塔の塔頂
からアクリル酸エステル、水および未反応アルコールを
留去させる一方、アクリル酸を含む液を抜きだして循環
液としエステル化反応器に縦貫させることを特徴とする
アクリル酸エステルの製造方法である。以下に本発明を
更に詳しく説明する。[Means for Solving the Problems] As a result of earnest studies, the present inventors have found that acrylic acid and carbon number 1 to 1
When the esterification reaction of the lower aliphatic alcohol or alicyclic alcohol of 4 with a strongly acidic cation exchange resin as a catalyst, the esterification reaction is performed while adjusting the reaction temperature so that the conversion rate of acrylic acid is always constant. By doing so, the acrylic acid separation column can be operated in a stable state, the composition of the circulating liquid circulating in the esterification reactor is stable, the composition of the inlet liquid of the reactor is also stable, and the object of the present invention can be achieved. I found it. That is, the present invention uses acrylic acid and carbon number 1
To 4 lower aliphatic alcohols or alicyclic alcohols are supplied to an esterification reactor, and the reaction temperature is adjusted so that the conversion of acrylic acid is always constant in the reactor by using a strongly acidic cation exchange resin as a catalyst. And the composition of the feed liquid to the esterification reactor, which is composed of a raw material liquid newly fed to the acrylic acid and alcohol esterification reactor and a circulating liquid from the acrylic acid separation column, is always substantially constant. The resulting reaction product is introduced into the acrylic acid separation column, and the acrylic ester, water and unreacted alcohol are distilled off from the top of the acrylic acid separation column, while the acrylic acid is removed. A method for producing an acrylate ester, characterized in that a liquid containing an acid is extracted and made into a circulating liquid and is vertically passed through an esterification reactor. The present invention will be described in more detail below.
本発明で使用するアクリル酸は粗製アクリル酸及び精製
アクリル酸のいずれも使用可能であり、エステル化反応
後、アクリル酸分離塔から回収される未反応アクリル酸
も循環再使用させる。As the acrylic acid used in the present invention, both crude acrylic acid and purified acrylic acid can be used, and the unreacted acrylic acid recovered from the acrylic acid separation column after the esterification reaction is also recycled.
炭素数１〜４の低級の脂肪族アルコールまたは脂環式ア
ルコールの具体例としてはメタノール，エタノール，プ
ロパノール，ブタノール等が挙げられ、これらは直鎖状
のものであっても分岐を有するものであっても良い。ま
た、エステル化反応後、アクリル酸エステルを精製する
過程で回収される未反応アルコールを循環再使用しても
よい。Specific examples of the lower aliphatic alcohol or alicyclic alcohol having 1 to 4 carbon atoms include methanol, ethanol, propanol, butanol and the like, which may be linear or branched. May be. Further, after the esterification reaction, unreacted alcohol recovered in the process of purifying the acrylic ester may be reused by circulation.
本発明ではエステル化反応用の触媒として強酸性陽イオ
ン交換樹脂を用いる。多孔質またはゲルタイプの樹脂が
使用可能であるが多孔質タイプの樹脂が好適に用いられ
る。特に粗製アクリル酸を使用する場合には耐有機汚染
性に優れた多孔質タイプの樹脂を使用するのが好まし
い。多孔質の強酸性陽イオン交換樹脂としては架橋度２
〜16％，ポロシティ0.1〜1.0ml/g,平均細孔径100〜600
Åのものが好ましく使用でき、具体例としてはＣ−26C
（デュオライト社製）,PK−208,PK−216,PK−228（三菱
化成社製）,MSC−1,88（ダウ社製），アンバーリストー
16（ローム アンド ハース社製）,SPC−108,SPC−112
（バイエル社製）などが挙げられる。In the present invention, a strongly acidic cation exchange resin is used as a catalyst for the esterification reaction. A porous or gel type resin can be used, but a porous type resin is preferably used. Particularly when crude acrylic acid is used, it is preferable to use a porous type resin having excellent resistance to organic contamination. As a porous strong cation exchange resin, the degree of crosslinking is 2
〜16%, porosity 0.1〜1.0ml / g, average pore size 100〜600
Å can be preferably used, and C-26C is a specific example.
(Duolite), PK-208, PK-216, PK-228 (Mitsubishi Kasei), MSC-1,88 (Dow), Amberlystow
16 (made by Rohm and Haas), SPC-108, SPC-112
(Manufactured by Bayer) and the like.
エステル化反応は反応器入口液、出口液の組成を分析す
るなどしてアクリル酸の転化率を監視し、該転化率が常
に一定になる様に反応温度を調節しながら行なわれる。
好ましくは運転を開始して定常状態に達したときのアク
リル酸の転化率を基準として、±５％以内、より好まし
くは±３％以内の範囲に納まる転化率とする。また、高
い選択率を得るためにアクリル酸の転化率は15〜50％の
範囲であるのが好ましい。この場合、反応温度を調節し
ても、転化率は一定であって選択率も高いために反応器
出口の液組成があまり変化せずに安定した運転条件が保
たれる。The esterification reaction is carried out while monitoring the conversion rate of acrylic acid by analyzing the composition of the liquid at the inlet and the liquid at the outlet of the reactor and adjusting the reaction temperature so that the conversion is always constant.
The conversion rate is preferably within ± 5%, more preferably within ± 3%, based on the conversion rate of acrylic acid when the operation is started and reaches a steady state. Further, in order to obtain a high selectivity, the conversion rate of acrylic acid is preferably in the range of 15 to 50%. In this case, even if the reaction temperature is adjusted, the conversion rate is constant and the selectivity is high, so that the liquid composition at the outlet of the reactor does not change so much and stable operation conditions are maintained.
また、エステル化反応は、上記のように転化率が常に一
定になるように反応温度を調節するとともに、上記のア
クリル酸およびアルコールの新規原料液と上記の循環液
とからなるエステル化反応器への供給液の組成を実質的
に一定にしながら行う。かくして、エステル化反応器中
の反応液の組成が実質的に一定に維持され、前記本発明
の目的が達成される。Further, in the esterification reaction, the reaction temperature is adjusted so that the conversion rate is always constant as described above, and the esterification reactor is composed of the above novel raw material liquid of acrylic acid and alcohol and the above circulating liquid. The composition of the feed solution is substantially constant. Thus, the composition of the reaction liquid in the esterification reactor is kept substantially constant, and the above-mentioned object of the present invention is achieved.
運転開始から触媒を寿命として交換するまでの反応温度
範囲は目的とするエステル化反応によって異なるが、通
常50〜110℃である。また、エステル化反応は液相にて
行なわれ、複数の反応器を順次切り換えて触媒交換しつ
つ連続操業することも可能である。The reaction temperature range from the start of operation to the replacement of the catalyst as the life is different depending on the target esterification reaction, but is usually 50 to 110 ° C. Further, the esterification reaction is carried out in the liquid phase, and it is also possible to successively switch a plurality of reactors and exchange the catalysts to continuously operate.
エステル化反応においては、通常用いられているような
重合禁止剤を使用することができる。使用される重合禁
止剤としては例えばハイドロキノン，メトキシハイドロ
キノン，フェノチアジン，ヒドロキシルアミン，フェニ
レンジアミンなどが挙げられる。なお、反応を分子状酸
素の存在下で行うと重合禁止剤の効果を更に高めること
ができる。In the esterification reaction, a polymerization inhibitor that is commonly used can be used. Examples of the polymerization inhibitor used include hydroquinone, methoxyhydroquinone, phenothiazine, hydroxylamine, and phenylenediamine. If the reaction is carried out in the presence of molecular oxygen, the effect of the polymerization inhibitor can be further enhanced.
このようにして得られたエステル化反応生成物はアクリ
ル酸分離塔に導いて、アクリル酸分離塔の塔頂からアク
リル酸エステル，水および未反応アルコールを留去させ
る。一方、アクリル酸分離塔の塔底から実質的に全量の
アクリル酸を含む液を抜きでして循環液としてエステル
化反応器に循環させる。The esterification reaction product thus obtained is introduced into the acrylic acid separation column, and the acrylic ester, water and unreacted alcohol are distilled off from the top of the acrylic acid separation column. On the other hand, a liquid containing substantially the entire amount of acrylic acid is extracted from the bottom of the acrylic acid separation column and circulated as a circulating liquid in the esterification reactor.
アクリル酸分離塔においては、前述したとおり、塔底温
度が規定温度以下に納まるように完全にアクリル酸を分
離せずにアクリル酸エステルを含んだ状態で塔底液を抜
き出す。次いで、塔底液は循環液としてエステル化反応
器に循環するのであるが、エステル化反応を進めるうえ
では該循環液組成はアクリル酸エステルおよび水を減ら
しアクリル酸を増やす方が有利になる。従ってアクリル
酸分離塔から排出される塔底液は、目的とするエステ
ル、反応条件によっても異なるが、アクリル酸の濃度が
50重量％以上、より好ましくは60重量％以上、また水の
濃度が５重量％以下、より好ましくは２重量％以下であ
るのが望ましい。In the acrylic acid separation column, as described above, the column bottom liquid is withdrawn in the state of containing the acrylic ester without completely separating the acrylic acid so that the column bottom temperature falls below the specified temperature. Next, the bottom liquid is circulated to the esterification reactor as a circulating liquid, and in terms of the composition of the circulating liquid, it is more advantageous for the composition of the circulating liquid to decrease the acrylic acid ester and water and increase the acrylic acid. Therefore, the bottom liquid discharged from the acrylic acid separation column will differ in concentration of acrylic acid, depending on the target ester and reaction conditions.
It is desirable that the concentration of water is 50% by weight or more, more preferably 60% by weight or more, and the concentration of water is 5% by weight or less, more preferably 2% by weight or less.
アクリル酸分離塔においてもエステル化反応に関して例
示したと同様の重合禁止剤を用いる。分子状酸素の存在
下で行うと重合禁止剤の効果を更に高めることができる
ことも同様である。アクリル酸分離塔塔底液は循環液と
してエステル化反応器に循環されるが、その一部を薄層
蒸発器に導いて重合物などの高沸点不純物を除去するな
ど適宜精製処理した後エステル化反応器に循環させる循
環液量は多すぎても少なすぎてもエステル化反応に必要
な樹脂量が増加するので好ましくない。循環液量は新規
供給量に対して１〜５倍量が適切である。Also in the acrylic acid separation column, the same polymerization inhibitor as that exemplified for the esterification reaction is used. Similarly, the effect of the polymerization inhibitor can be further enhanced by carrying out in the presence of molecular oxygen. The bottom liquid of the acrylic acid separation column is circulated as a circulating liquid to the esterification reactor, and a part of it is introduced to a thin-layer evaporator to appropriately purify it such as removing high boiling impurities such as polymerized products, and then esterification. If the amount of the circulating liquid circulated in the reactor is too large or too small, the amount of resin required for the esterification reaction increases, which is not preferable. The circulating liquid amount is appropriately 1 to 5 times the new supply amount.
次に、本発明の好適な実施態様を例示する第１図に従っ
て更に詳しく説明する。Next, a more detailed description will be given with reference to FIG. 1, which illustrates a preferred embodiment of the present invention.
ライン１よりアクリル酸、ライン２よりアルコール、ラ
イナ７より循環液を供給し、これら混合物を多孔質の強
酸性陽イオン交換樹脂を充填したエステル化反応器101
に供給する。エステル化反応器101において、反応器入
口３および出口４の液を分析してアクリル酸の転化率を
監視し、該転化率が常に一定になる様に反応温度を調節
しながらエステル化反応を行う。Esterification reactor 101 in which acrylic acid is supplied from line 1, alcohol is supplied from line 2, and a circulating liquid is supplied from liner 7, and the mixture is filled with a porous strong acid cation exchange resin.
Supply to. In the esterification reactor 101, the liquid at the inlet 3 and the outlet 4 of the reactor is analyzed to monitor the conversion rate of acrylic acid, and the esterification reaction is performed while adjusting the reaction temperature so that the conversion rate is always constant. .
生成エステル，未反応アクリル酸，未反応アルコールお
よび生成水からなるエステル化反応生成物をエステル化
反応器101の出口４から抜き出し、アクリル酸分離塔102
に供給して蒸留する。アクリル酸分離塔102の塔底から
実質的に全量の未反応アクリル酸を含む液を抜き出し、
循環液としてライン７よりエステル化反応器101へ循環
する。ここでアクリル酸分離塔塔底液の一部を薄層蒸発
器103に供給して重合物などの高沸点不純物をライン６
より系外に除去し、留出物を残りのアクリル酸分離塔塔
底液とともに循環する。An esterification reaction product consisting of the produced ester, unreacted acrylic acid, unreacted alcohol and produced water is extracted from the outlet 4 of the esterification reactor 101, and the acrylic acid separation column 102
And then distilled. Withdrawing a liquid containing substantially all unreacted acrylic acid from the bottom of the acrylic acid separation column 102,
It circulates from the line 7 to the esterification reactor 101 as a circulating liquid. Here, a part of the bottom liquid of the acrylic acid separation column is supplied to the thin layer evaporator 103 to remove high boiling impurities such as polymerized substances in the line 6.
It is further removed to the outside of the system, and the distillate is circulated together with the remaining bottom liquid of the acrylic acid separation column.
また、アクリル酸分離塔102の塔頂からは生成エステ
ル，未反応アルコールおよび生成水が留出し、受器104
にてエステル相と水相とに二相分離する。一部は還流液
としてアクリル酸分離塔102に循環する。ライン８より
エステル相を抜き出し、図外の精製工程に送ってアクリ
ル酸エステル製品を得る。一方、ライン９より水相を抜
き出し、図外のアルコール回収工程または廃水処理工程
に送る。In addition, the produced ester, unreacted alcohol and produced water are distilled out from the top of the acrylic acid separation column 102, and the receiver 104
The two phases are separated into an ester phase and an aqueous phase. A part of it circulates in the acrylic acid separation column 102 as a reflux liquid. The ester phase is extracted from the line 8 and sent to a refining process (not shown) to obtain an acrylic ester product. On the other hand, the water phase is extracted from the line 9 and sent to the alcohol recovery process or waste water treatment process not shown.
本発明においては、エステル化反応はアクリル酸の転化
率が常に一定になる様に行なわれるので、エステル化反
応生成物の組成は安定しており、アクリル酸分離塔102
の運転条件も安定して行なわれる。即ち、アクリル酸分
離塔102の操作温度は一定し、塔底から出され、反応器
に循環される循環液の組成も一定している。In the present invention, the esterification reaction is carried out so that the conversion rate of acrylic acid is always constant, so that the composition of the esterification reaction product is stable and the acrylic acid separation column 102
The operating conditions of are stable. That is, the operating temperature of the acrylic acid separation column 102 is constant, and the composition of the circulating liquid discharged from the bottom of the column and circulated in the reactor is also constant.
［実施例］ 更に、本発明を以下の実施例によって詳しく説明する。
なお、各実施例は第１図の装置を用いて行ない、アクリ
ル酸の転化率は反応器入口液、出口液のアクリル酸濃度
を分析して下記式に従って計算した。[Examples] Further, the present invention will be described in detail by the following examples.
Each example was carried out using the apparatus shown in FIG. 1, and the conversion rate of acrylic acid was calculated according to the following formula by analyzing the acrylic acid concentrations of the reactor inlet liquid and outlet liquid.
実施例１ 第１図の装置を用い、純度99.7重量％のアクリル酸およ
びメタノールを原料とし、エステル化反応器に多孔質の
陽イオン交換樹脂7.5lを充填してアクリル酸メチルの製
造を行なった。運転開始時（運転を開始して定常状態に
達したとき）及び運転開始から７ケ月後の状況は第１表
に示したとおりであった。 Example 1 Using the apparatus shown in FIG. 1, acrylic acid and methanol having a purity of 99.7% by weight were used as raw materials, and 7.5 l of a porous cation exchange resin was charged into an esterification reactor to produce methyl acrylate. . The conditions at the start of operation (when the operation started and reached a steady state) and seven months after the start of operation were as shown in Table 1.
運転中、反応器でのアクリル酸の転化率を一定に保つ為
に樹脂の経時劣化に伴い反応温度を徐々に上昇させた結
果、７ケ月間の連続運転後反応温度は67℃となったがこ
の間の反応温度の上昇割合はほぼ一定であった。また、
運転中はアクリル酸の転化率、エステル化反応生成物の
組成、アクリル酸分離塔の塔底温度、循環液の組成など
は安定していた。During operation, in order to keep the conversion of acrylic acid in the reactor constant, the reaction temperature was gradually increased as the resin deteriorated with time. As a result, the reaction temperature after continuous operation for 7 months was 67 ° C. During this period, the rate of increase in reaction temperature was almost constant. Also,
During the operation, the conversion rate of acrylic acid, the composition of the esterification reaction product, the bottom temperature of the acrylic acid separation column, the composition of the circulating liquid, etc. were stable.
実施例２ 実施例１と同じ純度99.7重量％のアクリル酸とブタノー
ルとを原料とし、エステル反応器に多孔量の陽イオン交
換樹脂20lを充填し、反応温度65℃にて実施例１に準じ
てアクリル酸ブチルの製造を開始した。 Example 2 Acrylic acid and butanol having the same purity as in Example 1 were used as raw materials, and the ester reactor was filled with 20 liters of a cation exchange resin having a porosity, and the reaction temperature was 65 ° C. according to Example 1. Production of butyl acrylate started.
運転を開始して定常状態に達したとき、各流量はアクリ
ル酸（ライン１）1.33kg/時，ブタノール（ライン２）
2.00kg/時，循環液（ライン７）6.66kg/時，アクリル酸
の転化率は28.5％、アクリル酸分離塔塔底温度は100℃
であった。When the operation started and reached a steady state, each flow rate was acrylic acid (line 1) 1.33 kg / hr, butanol (line 2).
2.00 kg / hr, circulating fluid (line 7) 6.66 kg / hr, acrylic acid conversion rate 28.5%, acrylic acid separation column bottom temperature 100 ° C
Met.
７ケ月間連続運転する間にエステル化反応温度は65℃か
らほぼ一定の割合で上昇し、76℃になった。しかし、７
ケ月間の連続運転中、アクリル酸の転化率、エステル化
反応生成物の組成、アクリル酸分離塔の塔底温度、循環
液の組成などは安定していた。During continuous operation for 7 months, the esterification reaction temperature increased from 65 ° C at a nearly constant rate to 76 ° C. But 7
During the continuous operation for a month, the conversion rate of acrylic acid, the composition of the esterification reaction product, the bottom temperature of the acrylic acid separation column, the composition of the circulating liquid, etc. were stable.
比較例１ 運転中の反応温度を76℃に保った他は実施例２と同様に
してアクリル酸ブチルの製造を実施した。その結果、樹
脂の経時劣化が起こり、アクリル酸の転化率は徐々に低
下し、アクリル酸分離塔の塔底温度は徐々に上昇して５
ケ月間で連続運転を停止せざるをえなかった。運転を開
始して定常常態に達したときのアクリル酸の転化率は3
5.0％であったのが運転停止時には17.5％に低下してお
り、実施例２に比べて樹脂寿命は明らかに短くなってお
り、単位触媒量当りの総生産量も少なかった。Comparative Example 1 Butyl acrylate was produced in the same manner as in Example 2 except that the reaction temperature during operation was kept at 76 ° C. As a result, deterioration of the resin over time occurs, the conversion rate of acrylic acid gradually decreases, and the bottom temperature of the acrylic acid separation column gradually increases to 5
I had no choice but to stop continuous operation for a month. The conversion rate of acrylic acid is 3 when the operation starts and reaches a steady state.
Although it was 5.0%, it decreased to 17.5% when the operation was stopped, the resin life was clearly shorter than that in Example 2, and the total production amount per unit catalyst amount was also small.
但し、反応器入口の液組成は徐々に変化するため、転化
率の低下が単位時間当りの生産量の低下を意味するもの
ではなく、単位時間当りの生産量は実施例１と同一であ
った。However, since the liquid composition at the reactor inlet gradually changed, the decrease in conversion rate did not mean the decrease in the production amount per unit time, and the production amount per unit time was the same as in Example 1. .
［発明の効果］ 本発明によれば、上記のアクリル酸およびアルコールの
新規原料液と上記の循環液とからなるエステル化反応器
への供給液の組成を一定にし、かつエステル化反応器中
での反応温度を50〜110℃の範囲で調節してアクリル酸
の転化率を一定になるようにすることにより、エステル
化反応器中での反応液の組成が実質的に一定になること
から、次のような効果が得られる。[Effects of the Invention] According to the present invention, the composition of the supply liquid to the esterification reactor consisting of the above-mentioned novel raw material liquid of acrylic acid and alcohol and the above-mentioned circulating liquid is kept constant, and in the esterification reactor. By adjusting the reaction temperature of 50 to 110 ° C. in order to make the conversion of acrylic acid constant, the composition of the reaction solution in the esterification reactor becomes substantially constant, The following effects can be obtained.
（１）触媒としてのイオン交換樹脂の膨潤、収縮、割れ
などの問題が防止でき、触媒寿命を長く維持ることがで
きる。(1) Problems such as swelling, shrinkage, and cracking of the ion exchange resin as a catalyst can be prevented, and the catalyst life can be maintained for a long time.
本発明においては、エステル化反応器中の温度が規定の
温度に達した時点をもって触媒寿命とし、触媒交換を行
うが、上記のように触媒寿命が長くなることから、単位
触媒（樹脂）当りのアクリル酸エステルの総生産量が増
加する。In the present invention, the catalyst life is set at the time when the temperature in the esterification reactor reaches a specified temperature, and the catalyst exchange is performed. However, since the catalyst life becomes long as described above, the unit catalyst (resin) Increases the total production of acrylic ester.
（２）常に一定の液組成で運転できることから、アクリ
ル酸分離塔の運転条件も安定し、アクリル酸分離塔での
塔底温度の上昇による重合物の増加を防止することがで
きる。(2) Since the liquid composition can always be operated with a constant liquid composition, the operating conditions of the acrylic acid separation column are stable, and it is possible to prevent an increase in polymer due to a rise in the bottom temperature of the acrylic acid separation column.
第１図は本発明の好適な実施態様を例示するフローシー
ト図を表わす。 101…エステル化反応器 102…アクリル酸分離塔 103…薄層蒸発器、104…受器 １…アクリル酸供給ライン ２…アルコール供給ライン ３…エステル化反応器入口 ４…エステル化反応器出口 ５…アクリル酸分離塔塔底液抜き出しライン ６…高沸点物抜き出しライン ７…循環液供給ライン ８…エステル相抜き出しライン ９…水相抜き出しラインFIG. 1 represents a flow sheet diagram illustrating a preferred embodiment of the present invention. 101 ... Esterification reactor 102 ... Acrylic acid separation column 103 ... Thin layer evaporator, 104 ... Receiver 1 ... Acrylic acid supply line 2 ... Alcohol supply line 3 ... Esterification reactor inlet 4 ... Esterification reactor outlet 5 ... Acrylic acid separation column tower bottom liquid withdrawal line 6 ... High boiling point material withdrawal line 7 ... Circulating liquid supply line 8 ... Ester phase withdrawal line 9 ... Water phase withdrawal line
───────────────────────────────────────────────────── フロントページの続き (72)発明者 馬場 将夫 兵庫県姫路市網干区興浜字西沖992番地の １ 日本触媒化学工業株式会社姫路製造所 内 審査官 唐木 以知良 (56)参考文献 特公 昭63−20415（ＪＰ，Ｂ２) 特公 昭59−12102（ＪＰ，Ｂ２) 「化学実験法」（1960−５−１）東京化 学同人，210−212、 「触媒工学講座 ３ 触媒装置および設 計」（昭42−７−10）地人書館，367、 「別冊化学工業 26−８ 触媒化学の進 歩−有効利用法と実際−」（昭57−５− １）化学工業社，33、 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Masao Baba Inventor Masao Baba 1 992 Nishikioki, Kamahama, Aboshi-ku, Himeji-shi, Hyogo Ichira Karaki (56) Bibliography Shoji 63 -20415 (JP, B2) JP-B-59-12102 (JP, B2) "Chemical Experimental Method" (1960-5-1) Tokyo Kagaku Dojin, 210-212, "Catalyst Engineering Course 3 Catalytic Equipment and Design" (Sho 42-7-10) Jishin Shokan, 367, "Separate Volume Chemical Industry 26-8 Progress in Catalytic Chemistry-Effective Utilization and Practical Use-" (Sho 57-5-1) Kagaku Kogyosha, 33,
Claims (1)
アルコールまたは脂環式アルコールとをエステル化反応
器に供給し、該反応器にて強酸性陽イオン交換樹脂を触
媒としてエステル化反応させ、得られた反応生成物をア
クリル酸分離塔に導いて、アクリル酸分離塔の塔頂から
アクリル酸エステル、水および未反応アルコールを留去
させる一方、アクリル酸分離塔の塔底から実質的に全量
のアクリル酸を含む液を抜き出して循環液としてエステ
ル化反応器に循環させてアクリル酸エステルを製造する
際に、 （イ）上記のアクリル酸およびアルコールのエステル化
反応器に新規に供給する原料液と上記の循環液とからな
るエステル化反応器への供給液の組成を実質的に一定に
し、かつ （ロ）エステル化反応器中での反応温度を50〜110℃の
範囲で調節してアクリル酸の転化率を実質的に一定に維
持する、 ことを特徴とするアクリル酸エステルの製造方法。1. Acrylic acid and a lower aliphatic alcohol having 1 to 4 carbon atoms or an alicyclic alcohol are supplied to an esterification reactor, and the esterification is carried out in the reactor using a strongly acidic cation exchange resin as a catalyst. The reaction product obtained by the reaction is introduced into an acrylic acid separation column, and the acrylic ester, water and unreacted alcohol are distilled off from the top of the acrylic acid separation column, while the acrylic acid separation column is substantially separated from the bottom of the column. (A) When the acrylic acid ester is produced by extracting a liquid containing all the acrylic acid and circulating it as a circulating liquid in the esterification reactor, (a) supplying it to the esterification reactor of acrylic acid and alcohol newly. The composition of the feed liquid to the esterification reactor composed of the raw material liquid and the circulating liquid described above is substantially constant, and (b) the reaction temperature in the esterification reactor is in the range of 50 to 110 ° C. A method for producing an acrylic acid ester, characterized in that the conversion rate of acrylic acid is maintained substantially constant by adjusting with.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1100168A JPH0686406B2 (en) | 1989-04-21 | 1989-04-21 | Method for producing acrylic ester |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1100168A JPH0686406B2 (en) | 1989-04-21 | 1989-04-21 | Method for producing acrylic ester |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02279655A JPH02279655A (en) | 1990-11-15 |
| JPH0686406B2 true JPH0686406B2 (en) | 1994-11-02 |
Family
ID=14266789
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1100168A Expired - Lifetime JPH0686406B2 (en) | 1989-04-21 | 1989-04-21 | Method for producing acrylic ester |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0686406B2 (en) |
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| US6605738B1 (en) | 1996-05-29 | 2003-08-12 | Union Carbide Chemicals & Plastics Technology Corporation | Processes for refining butyl acrylate |
| CN1069893C (en) * | 1996-08-03 | 2001-08-22 | 中国石化齐鲁石油化工公司 | Process for producing methyl methacrylate and ethyl methacrylate |
| KR100380017B1 (en) * | 1998-12-30 | 2003-09-26 | 주식회사 엘지화학 | Manufacturing method of unsaturated carboxylic ester by continuous process |
| JP5108249B2 (en) * | 2006-04-20 | 2012-12-26 | 三井化学株式会社 | Method for producing thiol compound |
| JP4160087B2 (en) | 2006-07-11 | 2008-10-01 | 株式会社日本触媒 | Method for producing acrylic ester |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54106412A (en) * | 1978-02-08 | 1979-08-21 | Kyowa Yuka Kk | Method of purifying ester |
| JPS58159442A (en) * | 1982-03-17 | 1983-09-21 | Nippon Kayaku Co Ltd | Preparation of acrylic or methacrylic ester |
| JPS5912102A (en) * | 1982-07-12 | 1984-01-21 | Toshiba Corp | Labyrinth packing |
| JPH075981B2 (en) * | 1986-07-12 | 1995-01-25 | 新日本製鐵株式会社 | Side burner combustion control method for continuous heating furnace |
-
1989
- 1989-04-21 JP JP1100168A patent/JPH0686406B2/en not_active Expired - Lifetime
Non-Patent Citations (3)
| Title |
|---|
| 「別冊化学工業２６−８触媒化学の進歩−有効利用法と実際−」（昭５７−５−１）化学工業社，３３、 |
| 「化学実験法」（１９６０−５−１）東京化学同人，２１０−２１２、 |
| 「触媒工学講座３触媒装置および設計」（昭４２−７−１０）地人書館，３６７、 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02279655A (en) | 1990-11-15 |
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