dvr DI Ethanol Amine

If RXH is not acid enough to release a proton at alkaline pH, as it is the case with amines, then the reaction has to be carried out in two steps. During the first step the first EO mole is added at acid pH, so that the amine is transformed in ammonium. The reaction produce the mono-, di- and tri-ethanol amines. 

Proton release from ammonium NH4%u2192 NH+ H(here RX– is NH3) Then, the three condensation reactions: 

 

NHEO %u2192 NH2CH2CH2OH (mono-ethanol amine MEA) 
NH
2CH2CH2OH + EO %u2192 NH(CH2CH2OH)(di-ethanol amine DEA) 
NH-(CH
2CH2OH)EO %u2192 N(CH2CH2OH)(tri-ethanol amine TEA) 

With an alkyl amine, first the alkyl ammoniumion is formed and it is deprotonated: 

RNH3%u2192 RNH+ H(here RX– is RNH2)
RNH
EO %u2192 RNH-CH2CH2OH (mono-ethanol alkyl amine) 
RNH-CH
2CH2OH + EO %u2192 RN(CH2CH2OH)(di-ethanol alkyl amine) 

Once the ethanol amine is attained, the EO polycondensation is carried out at alkaline pH as previously. In many instance the first ethoxylation is stopped when the monoethanol alkyl amine is formed in order to avoid the polycondensation in more than one chain. 

Application:
PRODUCT NAME    :  DI ETHANOL AMINE
CAS number     :  
UN number    :  
Formula    : (HOCH2CH2)2NH
Odour   : AMMONIA LIKE
Solubility in water   : COMPLETE
Density   : 1.09     at 20   oC
Boiling point    : 269 oC
Melting point    : 28 oC
Viscosity  :  
Flashpoint      : 152 oC
Explosive limits    : 0.1 mbar at 20 oC
Vapour pressure   : 0.1 mbar at 20 oC
Skin absorption/irritation       : YES
TLV       Country  NL            Year  1995      : 3 ppm              15        mg/m3
Pollution category    1994       : D

Note: This article uses material from the http://rxmarine.com/