CN1238247C - 制备不含盐的羟胺水溶液的方法 - Google Patents
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Abstract
本发明涉及一种通过在具有至少两个机械塔盘的板式塔中蒸馏不含盐的羟铵盐水溶液而制备高纯度羟胺水溶液的方法。所述方法的特征在于在板式塔的横截面上将填料设置于该塔的至少两个塔盘之间。
Description
本发明涉及一种通过在具有至少两个机械塔盘的板式塔中蒸馏不含盐的羟胺水溶液而制备高纯度羟胺水溶液的方法,其中在板式塔的横截面上将填料设置于该塔的至少两个塔盘之间。
高纯度的浓缩羟胺水溶液尤其用于电子工业中,例如与其他用于清洁印刷电路板或硅晶片的物质结合。为了用于电子工业中,通常要求杂质,尤其是金属离子的浓度充分低于1ppm,即要求“电子级”仪器。同时,对羟胺水溶液的纯度要求正不断增加。
高纯度的浓缩羟胺水溶液通常由不含盐的羟胺水溶液制备。
羟胺以羟铵盐大规模生产,通常以硫酸羟铵生产。为了制备不含盐的羟胺水溶液,用碱处理羟铵盐的水溶液并将羟胺水溶液与该混合物分离,通常是通过蒸馏,例如根据US-A-5,472,679、WO 97/22551、WO98/57886、DE 1954775.8、WO 99/07637。在这里通常得到稀释的不含盐的羟胺水溶液。
高纯度的浓缩羟胺水溶液通常由该类稀释的不含盐的羟胺水溶液通过再次蒸馏而得到,例如根据US-A-5,472,679、WO 97/22551、WO 98/57886、DE 1954775.8、WO 99/07637。
EP 188 387 A2公开了一种填充的分馏塔,其在进料管线和取出位置之上和之下具有机械塔盘,这些塔盘的特征在于其压降较高且液体滞留量较高,从而改善了因塔内容物的供入或取出而可能作用于填料的任何波动。该塔尤其在待分馏的料流以过冷或过热状态通入该塔中时被推荐。K.Sattler(编辑):Thermische Trennverfahren,第3版,Wiley-VCH,Weinheim2001,第242-249页给出了各种填料和填充塔的综述。D.W.Green(编辑):Perry’s Chemical Engineer’s Handbook,McGraw-Hill,纽约1997,第12-41至14-61页给出了气-液接触设备如塔盘或板式塔以及规整填料、散装填料和用规整填料和散装填料填充的塔的综述。
US 6 235 162公开了用于提纯羟胺溶液的两步法,其涉及的第一步中将挥发性成分(如有机溶剂、氨、氮气或其他气体)经由填充塔从溶液中排出。随后的第二步包括将残留在接收烧瓶中且已经除去挥发性成分的羟胺溶液进行闪蒸以除去非挥发性成分。
含羟胺的水溶液的蒸馏甚至在实验室规模上也被认为是特别危险的操作:见Roth-Weller:Gefhrliche Chemische Reaktionen,Stoffin-formationen Hydroxylamin(用于羟胺的危险化学反应、物质信息),第3页,1984,2,Eco-med-Verlag。
因此,上述蒸馏需要高度技术复杂性和大量时间。
此外,尽管使用了二次蒸馏,但高纯度的浓缩羟胺水溶液仍不希望地大量含有来自其制备的杂质,如硫酸钠或其他金属化合物。
本发明的目的是提供一种通过蒸馏制备高纯度的浓缩羟胺水溶液的方法,其中高纯度的浓缩羟胺水溶液以很少的杂质含量得到而不增加技术复杂性、时间或安全危险。
在本发明范围内的高纯度应理解为指金属离子含量低于1ppm且羟胺含量基于该溶液大于20重量%。
因此,本发明提供了一种通过在具有至少两个机械塔盘的板式塔中蒸馏不含盐的羟胺水溶液而制备金属离子含量低于1ppm且羟胺含量大于20重量%的高纯度羟胺水溶液的方法,其中在板式塔的横截面上将填料设置于该塔的至少一个塔盘上方。
在本发明方法中,使用不含盐的羟胺水溶液。该溶液的制备本身是已知的且例如可按US-A-5,472,679、WO 97/22551、WO 98/57886、DE 1954775.8或WO 99/07637中的方法进行。
该类不含盐的羟胺水溶液通常具有的羟胺含量为10-300g/l,优选80-150g/l且杂质如硫酸钠或金属离子的含量为0.005-25ppm。
根据本发明,将不含盐的羟胺水溶液在具有至少10个机械塔盘,优选10-50个机械塔盘的板式塔中进行蒸馏。
合适的塔盘包括错流式塔盘,如多孔板塔盘、浮阀塔盘、泡罩塔盘和槽形泡罩塔盘,或双流塔盘,优选多孔板塔盘。各塔盘之间的距离应为200-900mm,优选300-600mm。
塔和塔盘可以由非金属材料如玻璃、陶瓷、塑料制成。这防止了金属离子引发的分解。然而,令人惊奇的是已经发现该塔还可由特殊的金属材料如铂、银或锆制成而不显著增加羟胺分解。
有利的是使用降膜蒸发器来加热塔底,但当然也可使用其他常规底部加热器,如自然循环或强制循环蒸发器、板式换热器等。
在浓缩器段中的回流比可以有利地调节为0.2-2。
根据本发明,在该板式塔的横截面上在该塔的至少一个塔盘上方设置常规填料如拉西环、鲍尔环、鞍形填料;现代高性能填料如Hiflow环(购自Rauschert(德国Steinwiesen))、Super-Raschig环(购自Raschig(德国Ludwigshafen))、Cascade-Mini环(购自Koch-Glitsch(美国Wichita))、IMTP环(购自Norton(美国Akron))或Nutter环(购自Sulzer Chemtech(瑞士Wintherthur));或规整填料如Mellapak、Mellapak Plus或织物填料,优选现代高性能填料。
填料应对要蒸馏的溶液呈惰性,例如由塑料或特殊金属材料组成,优选由全氟化塑料(如TFM、PFA、Teflon)组成。
填料在塔盘之间的填充高度应为50-300mm,优选100-200mm。填料床与其上方安装填料床的塔盘之间的距离为0-600mm,优选100-300mm。填料床与其下方安装填料床的塔盘之间的距离为0-300mm,优选30-100mm。
在使用本发明方法之前,可能有利的是加入稳定剂。合适的稳定剂本身已知且可市购。
该羟胺溶液可以有利地在该板式塔的理论塔盘数的约三分之一的高度处供入。在塔顶得到基本不含羟胺的水,而在塔底得到其浓度取决于蒸馏条件的羟胺溶液。
通常而言,将蒸馏塔在1-200kPa(0.01-2巴),优选5-120kPa(0.05-1.2巴),特别优选30-110kPa(0.3-1.1巴)的压力下操作,该压力在每种情况下是指塔顶/底压力。羟胺待浓缩的程度越大,蒸馏必须越温和(低压和低温)。蒸馏可以连续或间歇进行。
蒸馏塔中的温度取决于操作蒸馏塔的压力。它们通常为10-160℃,优选60-110℃。
在蒸馏塔顶部取出的水或蒸气可以直接或在压缩或作为汽提蒸汽过热之后再循环到用于本发明方法的塔的底部,或可以作为废水供入废水处理工厂。
合适的话,可以在进料塔盘上方安装用于分离夹带液滴的装置,如除沫器。
通常以塔底产物得到浓缩的羟胺水溶液,其优选具有的羟胺含量大于20重量%,优选大于40重量%,尤其大于50重量%且金属离子(尤其是来自其制备或用于制备和回收的材料的金属离子)低于1ppm,尤其是低于0.1ppm。
通过本发明方法得到的高纯度羟胺水溶液具有的纯度高于由已知蒸馏方法得到的溶液。此外,羟胺因冲洗水的损失较低。再有,与已知方法相比,蒸馏混合物在塔中的停留时间更短,因此热应力更低。另外,对于相同的塔尺寸和相同的塔内滞留量,该塔的容量增加。若该塔包括除沫器,则与已知方法相比对该除沫器的负荷得以减轻。
实施例
对比例1
在具有33块塔盘且直径为1.3m的板式塔中,将8.9重量%的羟胺(游离碱)水溶液从下面以2.2t/h加入8块塔盘中。
在顶部以1.9t/h取出羟胺含量为1500ppm(重量)的水,回流速率为0.9t/h且以10kg/h加入稳定剂。
在塔底以350kg/h取出50重量%羟胺水溶液。
跨越该塔的压降为100毫巴,塔底蒸发器中的能量输入为2.8t/h蒸汽。
实施例1
程序同对比例1,不同的是在每种情况下在塔盘上设置150mm高的Hiflow环38/1(Rauschert,Steinwiesen,德国)的床。
得到与对比例1相同的结果,但以顶部产物得到的水仅含1000ppm(重量)的羟胺。
实施例2
程序同实施例1,不同的是进料量为3.4t/h。
在顶部以2.9t/h取出羟胺含量为1000ppm(重量)的水,回流速率为1.4t/h且以15kg/h加入稳定剂。
在塔底以540kg/h取出50重量%羟胺水溶液。
跨越该塔的压降为130毫巴,塔底蒸发器中的能量输入为4.3t/h蒸汽。
Claims (6)
1.一种通过在具有至少两个机械塔盘的板式塔中蒸馏不合盐的羟胺水溶液而制备金属离子含量低于1ppm且羟胺含量大于20重量%的高纯度羟胺水溶液的方法,其中在板式塔的横截面上将填料设置于该塔的至少一个塔盘上方。
2.如权利要求1所要求的方法,其中该板式塔具有至少10个机械塔盘。
3.如权利要求2所要求的方法,其中该板式塔具有10-50个机械塔盘。
4.如权利要求1-3中任一项所要求的方法,其中所用填料为常规填料、现代高性能填料或规整填料。
5.如权利要求1-3中任一项所要求的方法,其中在蒸馏塔中的温度为10-160℃。
6.如权利要求1-3中任一项所要求的方法,其中所用板式塔为具有错流式塔盘或双流塔盘的塔。
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DE10131788.3 | 2001-07-04 | ||
DE10131788A DE10131788A1 (de) | 2001-07-04 | 2001-07-04 | Verfahren zur Herstellung einer salzfreien, wässrigen Hydroxylaminlösung |
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CN1524061A CN1524061A (zh) | 2004-08-25 |
CN1238247C true CN1238247C (zh) | 2006-01-25 |
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US (1) | US7029557B2 (zh) |
EP (1) | EP1406833B1 (zh) |
JP (1) | JP4286132B2 (zh) |
KR (1) | KR100859578B1 (zh) |
CN (1) | CN1238247C (zh) |
AT (1) | ATE282580T1 (zh) |
CA (1) | CA2451869C (zh) |
DE (2) | DE10131788A1 (zh) |
ES (1) | ES2232775T3 (zh) |
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DE10314492B4 (de) * | 2003-03-27 | 2008-10-16 | Domo Caproleuna Gmbh | Verfahren zur Herstellung einer wässrigen Lösung von Hydroxylamin |
US8457841B2 (en) | 2007-08-31 | 2013-06-04 | GM Global Technology Operations LLC | Suspension system with optimized damping response |
US8428819B2 (en) | 2007-08-31 | 2013-04-23 | GM Global Technology Operations LLC | Suspension system with optimized damper response for wide range of events |
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EP0925109B1 (de) * | 1997-07-04 | 2009-04-01 | Kühni Ag | Einbauten für stoffaustauschkolonnen |
DE19733681A1 (de) | 1997-08-04 | 1999-02-11 | Basf Ag | Verfahren zur Herstellung einer wäßrigen Lösung von freiem Hydroxylamin |
US6235162B1 (en) | 1998-05-28 | 2001-05-22 | Sachem, Inc. | Ultrapure hydroxylamine compound solutions and process of making same |
DE19936380A1 (de) * | 1999-08-03 | 2001-02-08 | Basf Ag | Geordnete Packung zum Wärme- und Stoffaustausch |
-
2001
- 2001-07-04 DE DE10131788A patent/DE10131788A1/de not_active Withdrawn
-
2002
- 2002-07-02 KR KR1020037017310A patent/KR100859578B1/ko active IP Right Grant
- 2002-07-02 AT AT02767163T patent/ATE282580T1/de active
- 2002-07-02 CA CA002451869A patent/CA2451869C/en not_active Expired - Fee Related
- 2002-07-02 MX MXPA03011842A patent/MXPA03011842A/es active IP Right Grant
- 2002-07-02 EP EP02767163A patent/EP1406833B1/de not_active Expired - Lifetime
- 2002-07-02 DE DE50201592T patent/DE50201592D1/de not_active Expired - Lifetime
- 2002-07-02 CN CNB028135326A patent/CN1238247C/zh not_active Expired - Lifetime
- 2002-07-02 WO PCT/EP2002/007271 patent/WO2003004407A1/de active IP Right Grant
- 2002-07-02 ES ES02767163T patent/ES2232775T3/es not_active Expired - Lifetime
- 2002-07-02 JP JP2003510386A patent/JP4286132B2/ja not_active Expired - Lifetime
- 2002-07-02 US US10/482,212 patent/US7029557B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
EP1406833A1 (de) | 2004-04-14 |
WO2003004407A1 (de) | 2003-01-16 |
US7029557B2 (en) | 2006-04-18 |
CN1524061A (zh) | 2004-08-25 |
JP4286132B2 (ja) | 2009-06-24 |
KR20040018415A (ko) | 2004-03-03 |
JP2004533392A (ja) | 2004-11-04 |
KR100859578B1 (ko) | 2008-09-23 |
MXPA03011842A (es) | 2005-03-07 |
US20040149564A1 (en) | 2004-08-05 |
DE50201592D1 (de) | 2004-12-23 |
EP1406833B1 (de) | 2004-11-17 |
DE10131788A1 (de) | 2003-01-16 |
ATE282580T1 (de) | 2004-12-15 |
ES2232775T3 (es) | 2005-06-01 |
CA2451869C (en) | 2009-11-24 |
CA2451869A1 (en) | 2003-01-16 |
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