Catalytic method for the manufacture of triethylenediamine

Cyclic and acyclic hydroxyethyl ethylenepolyamines are converted to triethylenediamine when using a catalyst composed of zirconia or titania to which from about 0.5 to about 7 wt. % of phosphorous has been thermally chemically bonded in the form of phosphate linkages.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a catalytic method for the preparation of 
diazabicyclo-(2.2.2.)-octane (triethylenediamine). More particularly, this 
invention relates to a catalytic method for the manufacture of 
triethylenediamine from hydroxyethyl derivatives of cyclic and acyclic. 
Still more particularly, this invention is directed to the use of titania 
and zirconia catalysts to which a minor amount of phosphorus has been 
thermally chemically bonded at the surface thereof in the form of 
phosphate linkages. Even more particularly, the present invention is 
directed a continuous process for the manufacture of triethylenediamine 
from hydroxyethyl derivatives of cyclic and acyclic ethylenepolyamines by 
passing such feedstocks over a bed of catalyst in a reaction zone wherein 
the catalyst is composed of pellets of titania and/or zirconia to which a 
minor amount of phosphorus (0.5 to 7 wt. %) has been thermally chemically 
bonded to the surface in the form of phosphate linkages. 
2. Prior Art 
The catalysts used in the practice of the process of the present invention 
are disclosed in Vanderpool U.S. Pat. No. 4,588,842, a division of 
abandoned Vanderpool U.S. application Ser. No. 455,160, filed Jan. 3, 
1983, upon which is based European patent application Ser. No. 
83,307,520.3 published Aug. 28, 1984, wherein they are disclosed as useful 
in promoting the reaction of ethylenediamine with ethanolamine to provide 
essentially linear polyethylenepolyamine reaction products. Minor 
quantities of cyclic products are also formed. 
It has heretofore been proposed to manufacture triethylenediamine from a 
wide variety of cyclic and acyclic polyethylenepolyamines. For example, it 
has been proposed to use solid cracking catalysts such as silica-alumina 
cracking catalysts to manufacture triethylenediamine from feedstocks such 
as polyethylenepolyamines (Herrick U.S. Pat. No. 2,937,176), from mixtures 
of diethanolamine with ethylenediamine (Mascioll U.S. Pat. No. 2,977,364), 
from N-aminoethyl piperazine (Krause U.S. Pat. No. 2,985,658), and from 
mixed feedstocks such as a feedstock containing both cyclic and acyclic 
polyethylenepolyamines such as N-aminoethyl piperazine and hydroxyethyl 
piperazine, diethylenetriamine and aminoethylethanolamine (Brader et al. 
U.S. Pat. No. 3,231,573). Brader U.S. Pat. No. 3,157,657 discloses the 
preparation of triethylenediamine from N-aminoethyl piperazine using a 
catalyst comprising tungsten or a base modified silica alumina cracking 
catalyst (Brader U.S. Pat. No. 3,120,526). U.S. Pat. No. 3,080,371 
discloses the use of an organic carboxylic acid to catalyze the conversion 
of hydroxyethyl piperazine to triethylenediamine. 
Brader et al. U.S. Pat. No. 3,297,701 discloses a method for the 
preparation of triethylenediamine by bringing an appropriate feedstock 
such as a cyclic or acyclic polyethylenepolyamine (e.g., N-aminoethyl 
piperazine, monoethanolamine, etc.) into contact with a phosphate of an 
enumerated metal (e.g., aluminum, calcium or iron phosphate). Also, Brader 
et al. propose the use of 2-(2-hydroxyethoxy)ethylamine as a feedstock for 
the synthesis of triethylenediamine in U.S. Pat. No. 3,172,891 using an 
aluminum phosphate catalyst. 
Muhlbauer et al. U.S. Pat. No. 3,285,920 is directed to a continuous 
process for the manufacture of piperazine and triethylenediamine wherein 
N-aminoethyl piperazine is converted to triethylenediamine using a 
silica-alumina cracking catalyst alone or modified with alkaline earth 
metal oxides, alkali metal oxides, zirconia, etc., a tungsten catalyst or 
a phosphate salt such as a phosphate salt of aluminum or iron. 
In Wells U.S. Pat. No. 4,405,784, a method for the manufacture of 
triethylenediamine from a cyclic or acyclic polyethylenepolyamine is 
discloses wherein the catalyst that is used is strontium diorthophosphate. 
SUMMARY OF INVENTION 
It has been surprisingly discovered in accordance with the present 
invention that hydroxyethyl derivatives of cyclic and acyclic 
ethylenepolyamines may be converted to triethylenediamine (TEDA) with 
excellent yields and excellent selectivities when using a catalyst 
composed of zirconia or titania to which from about 0.5 to about 7 wt. % 
of phosphorus has been thermally chemically bonded in the form of 
phosphate linkages. 
DETAILED DESCRIPTION OF THE EMBODIMENT 
Feedstocks 
The hydroxyethyl derivatives of cyclic and acyclic ethylenepolyamines that 
may be used as feedstocks in accordance with the present invention include 
feedstocks having the formula: 
EQU HO--CH.sub.2 CH.sub.2 --NH--CH.sub.2 CH.sub.2).sub.n --R (I) 
wherein R represents --OH or --NH.sub.2 and n is an integer having a value 
of 1 to 2. 
Another class of materials that may be used as feedstocks include cyclic 
ethylenepolyamines characterized by the following formula: 
##STR1## 
wherein R" represents --CH.sub.2 CH.sub.2 OH and R"' represents --CH.sub.2 
CH.sub.2 OH or H. 
Representative members of this class include compounds such as 
N-hydroxyethylpiperazine and bis-N-hydroxyethylpiperazine. 
Hydroxy terminated derivates of the foregoing materials may also be used as 
feedstocks in accordance with the present invention, such feedstocks being 
prepared by ethoxylating a cyclic or an acyclic polyethylenepolyamine 
having Formula I or II (where R" and R"' equal H), above, or a mixture of 
such amines with from about 0.5 to about 1.5 mole equivalents of ethylene 
oxide per mole of amine. 
Catalysts 
The pelleted catalyst compositions of the present invention are normally 
employed as a fixed bed of catalyst in a continuous reaction system. In a 
continuous process of this nature, the time of contact of the reactants 
with the catalyst is one of the interrelated factors that those skilled in 
the art will adjust, along with temperature, pressure, bed geometry, 
pellet size, etc. in order to obtain a desired rate of reaction and, hence 
a desired percentage of conversion of the reactants. In a continuous 
process, it is not necessary to drive the reaction to completion because 
unreacted feedstock components can be recycled to the reactor. 
It is customary to use cylindrically-shaped catalyst pellets having a 
diameter essentially equal to the length thereof, such as diameters and 
lengths ranging from about 0.794 mm (1/32 inch) to about 9.525 mm (3/8 
inch). It will be understood that the shape and dimensions of the pellets 
are not critical to the present invention and that pellets of any suitable 
shape and dimensions may be used, as desired, by one wishing to practice 
the process of the present invention. 
When cylindrical pellets of catalyst of the type described above are used, 
the weighted hourly space velocity may be varied within wide limits (e.g., 
0.1 to 5 w/hr/w) in order to obtain a desired rate of conversion, as 
explained above. Normally, space velocities of about 0.5 to 2 w/hr/w will 
be employed. 
Catalyst life is an important factor in conducting a continuous reaction. 
For example, if a catalyst is easily poisoned, or if catalyst pellets do 
not have good structural properties, the economics of the process will be 
seriously and adversely affected. 
The catalysts of the present invention are not particularly susceptible to 
poisoning so this normally does not present a problem. However, under the 
reaction conditions employed, amines of the type used and formed herein 
have the potential capability of leaching or otherwise adversely affecting 
the structural integrity of the pellets. In an extreme instance, catalyst 
pellets having good initial crush strength and surface hardness will be 
reduced to fines very rapidly when used under reaction conditions such as 
those employed herein. 
The pelleted catalyst compositions of the present invention are 
advantageously used in a continuous process for the continuous production 
of TEDA from cyclic and acyclic polyethylene polyamines and hydroxy 
terminated derivatives thereof. As shown herein, such catalyst 
compositions can be used for prolonged periods without the need for 
regeneration. Nevertheless, with the passage of time deactivation will 
tend to slowly occur. Deactivation can be measured qualitatively as the 
increase of temperature required to maintain an essentially constant 
conversion rate. 
When a catalyst composition of the present invention has become 
deactivated, or at least partially deactivated, in the sense that the 
temperature required to maintain a desired conversion level is considered 
to be excessive, the catalyst may be regenerated with ease with oxygen 
under controlled regeneration conditions as disclosed in Vanderpool U.S. 
Pat. No. 4,540,822. 
The regeneration temperature is preferably within the range of about 
350.degree. to about 550.degree. C. and more preferably within the range 
of 400.degree. to 500.degree. C. The oxygen is used in concentrations of 1 
to 20%, the balance being an inert gas such as nitrogen, flue gas, etc. 
In accordance with the preferred procedure the regeneration is initiated 
with a mixture of oxygen and inert gas containing from about 1 to about 3% 
oxygen, the balance being the inert gas. This mixture of oxygen and inert 
gas is passed through the catalyst bed at an initially comparatively 
moderate temperature of about 350.degree. to about 450.degree. C., and 
more preferably from about 400.degree. to about 450.degree. C. This may be 
considered as a pre-conditioning step and should be continued for a length 
of time within the range of about 0.5 to about 5 hours, such as a period 
of one to two hours. Thereafter the oxygen concentration can be 
progressively increased or increased in stages to a concentration of from 
about 3% to about 20% oxygen while increasing the temperature, if desired, 
to a temperature within the range of about 400.degree. to 550.degree. C., 
such as a temperature within the range of about 450.degree. to 500.degree. 
C. The oxygen treatment may be continued in this fashion suitably for 
about 2 to 10 hours. Thereafter the catalyst bed is flushed with an inert 
gas until it is cooled and it may then be restored to service. 
The catalyst compositions of the present invention are prepared by 
depositing a phosphorus compound on titania or zirconia, as described in 
greater detail in copending Vanderpool application Ser. No. 06/564,153 
filed Dec. 22, 1983, now U.S. Pat. No. 4,588,842, and entitled "Catalytic 
Preparation of Linear Polyethylenepolyamines" and in said Vanderpool 
European patent application Ser. No. 307,520.3 published Aug. 28. 1984. 
Pellets of titania or zirconia may be prepared by extrusion or by 
compaction in conventional pelleting apparatus using a pelleting aid such 
as graphite. It is also within the scope of the present invention to 
deposit the phosphorus compound on powdered titania or zirconia followed 
by pelleting and calcination. 
Any appropriate water soluble or liquid phosphorus compound can be used as 
a source of the phosphorus. For convenience, phosphoric acid will normally 
be used. However, other phosphorus compounds such as phosphoryl chloride 
(POCl.sub.3), phosphorous acid, polyphosphoric acid, phosphorus halides, 
such as phosphorus bromide, alkyl phosphates and alkyl phosphites such as 
trimethyl phosphate, triethyl phosphate, trimethyl phosphite, triethyl 
phosphite, etc. may be utilized. Also, a diamminohydrogen phosphate such 
as diammonium hydrogen phosphate, (NH.sub.4).sub.2 HPO.sub.4, 
dimethylamino hydrogen phosphate, (CH.sub.3).sub.2 NH.sub.2 PO.sub.4, 
diethylaminohydrogen phosphate (CH.sub.3 CH.sub.2).sub.2 NH.sub.2 
PO.sub.4, etc. may be used. 
As a matter of convenience, the normal practice is to use only one chemical 
as a phosphorus source (e.g., aqueous phosphoric acid). However, mixtures 
of two or more such reagents may be used if desired. 
Preferably the catalyst composition is prepared by impregnating a preformed 
pellet. A suitable procedure to be used is to heat the water soluble or 
liquid phosphorus compound at a temperature of about 100.degree. to about 
150.degree. C. and to then add pellets in an amount about equal to the 
volume of the heated liquid. This treatment should be continued from about 
0.5 to about 5 hours. At the end of that time, the resulting mixture of 
pellets and liquid is cooled, decanted to remove excess liquid followed by 
washing with an amount of water adequate to substantially completely 
remove unadsorbed liquid. Temperatures above 150.degree. C. can be used, 
if desired, but there is no particular advantage in doing so. 
It will be understood that the phosphorus that is present on a thus-treated 
pellet is not present as elemental phosphorus, but rather as phosphorus 
that is chemically bound, probably as an oxide, to the titania or zirconia 
support. This is demonstrated by the fact that repeated washing will not 
remove all of the phosphorus. However, the exact nature of the bonding is 
not completely understood. 
The amount of phosphorus that is bonded to the support is a function of 
heating and other conditions used in the treating step and is also a 
function of the chemical identity of the phosphorus compound that is used 
as a source of phosphorus. Under the treating conditions exemplified 
above, at least about 0.5 wt % of phosphorus is caused to bond (i.e., 
permanently adhere) to the pellets. There is an upper limit to the amount 
of phosphorus that bonds to the support. This upper limit is, as 
indicated, a function of both the treating conditions and the chemical 
used as a source of the phosphorus. Normally, the maximum amount of 
phosphorus that can be caused to bond to the pellets is about 7 wt. %. 
When the pellets are impregnated with the phosphorus compound at a 
temperature of at least about 100.degree. C., there is no absolute need to 
calcine the catalyst composition before use. However, the pellets can be 
calcined prior to use, if desired, as a precautionary measure and/or in 
order to still further improve the physical properties of the pellets. The 
pellets are suitably calcined at a temperature of about 200.degree. C. to 
about 800.degree. C. for a period of time within the range of 2 to 24 
hours; more preferably at a temperature of about 300.degree. C. to about 
600.degree. C. for about 4 to 16 hours. 
Other procedures can be used in adding phosphorus to the titania or 
zirconia. For example, the pellets can be treated with the phosphorus 
compound at ambient temperatures or at more modest elevated temperatures 
of less than about 100.degree. C. However, the catalyst should be calcined 
as described above without washing. 
Alternatively, the titania or zirconia can be treated with the 
phosphorus-containing compound in powdered form and the powder can 
thereafter be pelleted. If the treatment is conducted at a temperature of 
about 100.degree. C. or more, thermal activation will normally have been 
obtained and it will not be absolutely necessary to perform a calcining 
operation prior to use. If lower treating temperatures are used, calcining 
prior to use is normally a desired operation. The calcining operation can 
be conducted prior to or subsequent to the pelleting step. Any appropriate 
pelleting procedure of the type known to those skilled in the art may be 
used. For example, the treated powdered titania or zirconia can be mixed 
with graphite and/or other binders and compacted or extruded under 
conventional conditions. 
In any event, in-situ calcining will occur when the pelleted catalyst 
compositions are used to catalyze the reaction of the cyclic and/or 
acyclic polyethylenepolyamine and/or hydroxy terminated derivative 
feedstock at 300.degree. to 400.degree. C. to at least partially convert 
the feedstock to TEDA, as is hereinafter more fully set forth. 
Reaction Conditions 
The reaction of the present invention is conducted utilizing a feedstock of 
the present invention which is dissolved in water so as to form about a 5 
to about 50 wt. % aqueous solution of feedstock, such as a 20 wt. % 
aqueous solution, which is brought into contact with a catalyst in a batch 
reactor or in a continuous reactor. 
When the reaction is conducted in a batch reactor, the catalyst will 
preferably be employed in powdered form, whereas when the reaction is 
conducted on a continuous basis the catalyst is preferably employed in the 
form of pellets. 
The reaction is suitably conducted at a temperature of about 
250.degree.-400.degree. C. and, more preferably, at a temperature of about 
300.degree. to about 350.degree. C. 
The reaction is also preferably conducted at atmospheric pressure. 
Superatmospheric or subatmospheric pressures may be utilized if desired, 
but there is no particular advantage in doing so. 
When the reaction is conducted on a batch basis, the reaction time may 
suitably vary from about 1 to about 5 hours. When the reaction is 
conducted on a continuous basis, the feedstock may suitably be passed over 
a bed of pelleted catalyst at a liquid hourly space velocity (lhsv) of 
about 0.1 to about 10 volumes of the aqueous solution of the amine 
feedstock per volume of catalyst per hour. More preferably, the 1hsv will 
be from about 0.5 to about 2. 
It is not necessary to use either ammonia or hydrogen as feed components in 
the practice of the process of the present invention. 
Recovery and Purification 
The product of the present invention, triethylenediamine, is a compound 
having the formula: 
##STR2## 
Triethylenediamine in its pure form is a hygroscopic crystalline solid 
having a melting point of about 158.degree.-160.degree. C. 
Triethylenediamine is sparingly soluble in glycols such as ethylene 
glycol, propylene glycol, diethylene glycol, dipropylene glycol, etc. 
Also, when an aqueous reaction product containing triethylenediamine and 
propylene glycol is distilled, the triethylene diamine and propylene 
glycol can be distilled overhead as a triethylene diamine-propylene glycol 
azeotrope, thereby resulting in the recovery of a purified material in 
liquid form. This has the advantage of avoiding the necessity of 
recovering the triethylenediamine as a hygroscopic crystalline solid with 
all of the processing problems that are entailed in the handling of 
hygroscopic crystalline solids.

EXAMPLES 
I. Equipment and Procedures 
In all cases, these evaluations were performed in a 100 cc reactor 
constructed of 3/4 inch stainless steel tubing connected to 1/8 inch feed 
and effluent lines with swagelok fittings. The reactor tube was situated 
inside of a 3.times.3 inch aluminum block which was heated electrically 
with four 1000 watt strip heaters. Temperature control was achieved with a 
Thermoelectric controller monitoring thermocouples attached to the skin of 
the reactor body. The feed was charged to the reactor system with a 
Beckman 110A L.C. pump. For safety, pressure relief was provided by a 3000 
lb. rupture disk assembly although all runs were preformed at atmospheric 
pressure to minimize bimolecular reactions. The reactor effluent was 
collected in a glass jug and sampled after the system had lined-out at the 
proscribed temperature for at least 2.5 hours. 
In general the feedstock consisted of a 4:1 aqueous feed. For example, HEP 
feed consisted of 4 parts water by weight and 1 part HEP by weight. For 
the runs using nitrogen as a diluent, a different feed system was used; 
this will be described in detail hereinafter. 
The catalyst that was used was prepared from pelleted titania and 
polyphosphoric acid. It had about 2 wt. % of phosphorus thermally 
chemically bonded thereto and was prepared by dipping the preformed 
pellets into a 30% polyphosphoric acid solution, followed by decanting and 
calcining at 450.degree. C. 
Analysis of the reactor effluent was achieved using an OV-17 column in a 
Hewlett-Packard 5710A gas chromatograph. Analysis was on a water-free and 
feed-free basis. Since the conversion of HEP and BisHEP were nearly 
quantitative, the selectivities were close to calculated yields. 
Screening Reactions 
A. N-Hydroxyethyl Piperazine (HEP) Feedstock 
1. Aqueous Feedstock Water Diluent 
As described above, a 20 wt. % aqueous HEP solution was charged to the 
reactor with the results shown below. In this experiment, the purpose of 
the water is to further minimize bimolecular reactions that would be 
expected to result in the dimerization and polymerization of the HEP by 
acting as an inert diluent. In larger reactor systems water may be 
necessary as a heat transport medium. It must be emphasized that these 
selectivities are only approximate due to the nature of G.C. analysis. 
Data is presented in Table I. 
TABLE I.sup.a 
______________________________________ 
TEDA via HEP 
Ex. TEMP.sup.b 
Conv. TEDA PIP EtPIP Hvs.sup.c 
______________________________________ 
1 298 36 66 3.6 1.3 15 
2 311 86 83 4.2 3.4 7 
3 320 100 88 5.8 6.0 &lt;1 
4 330 100 83 7.1 9.3 &lt;1 
5 337 100 75 8.0 13.6 &lt;1 
______________________________________ 
.sup.a Data is basis GC analysis of crude reactor effluents. Selectivitie 
are approximate Area % on a water and feed free basis. 
.sup.b Temperature in degrees Centigrade. 
.sup.c Heavies are probably dimers of HEP. 
The obvious interpretations are: 
1. Increased temperatures increase byproduct formation and result in 
further reaction of an unidentified heavy by-product to give additional 
TEDA, piperazine and N-ethylpiperazine. 
2. Selectivity to the desired TEDA is optimized at the minimum temperature 
required for 100% HEP conversion. 
3. The heavy byproducts are apparently convertible to TEDA. 
2. Mass Balance 
The above process was run overnight using the equipment and procedures 
described in I for a material balance evaluation. A 99% mass balance was 
achieved across the reactor. The reactor effluent (obtained at 320.degree. 
C.) was about 14% TEDA or about 81% molar yield. This effluent was 
distilled in the presence of propylene glycol. A recovered molar yield of 
74% was obtained. 
In particular, 1868 g of effluent was obtained which contained about 257 g 
TEDA. This value was obtained by G.C. analysis using a correction factor 
obtained from a standard containing about 15% TEDA in water. 600 g of 
propylene glycol was added to the reactor effluent before distillation to 
create a TEDA/PG azeotrope thereby eliminating the distillation of solid 
TEDA. The TEDA/PG azeotrope has a 1:2 weight ratio. 600 g PG was used to 
give about 20% excess and assure a liquid overhead. 
______________________________________ 
Mass Balance Distillation 
Cut 1 to 185.degree. C. 
Very little TEDA 
5 g 
Cut 2 185-188.degree. C. 
PG with some TEDA 
10 g 
Cut 3 188-191.degree. C. 
33% TEDA in PG 202 g 
Btms Some TEDA 5 g 
Column holdup 15 g 
Total 237 g 
______________________________________ 
B. Crude HEP Feedstock 
The feedstocks discussed below were prepared in a high pressure laboratory 
by digesting the required amount of ethyleneoxide (EO) in an aqueous 
solution of piperazine (PIP) at 90.degree.-100.degree. C. for 2 hours. The 
organics were diluted to a 20 wt. % solution with distilled water and runs 
were made using the equipment and procedures of I. G.C. analysis of the 
crude reactor effluents are provided in Table II. 
TABLE II.sup.a 
______________________________________ 
TEDA via Crude HEP 
Ad- Conv. (%) Select. (%) 
Ex. duct.sup.b 
TEMP.sup.c 
HEP BisHEP TEDA PIP EtPIP 
______________________________________ 
6 0.5:1 290 54 59 78 20 -- 
7 " 296 72 -- 78 20 -- 
8 " 300 76 79 78 19 1 
9 " 306 88 100 79 18 1 
10 " 310 92 100 78 15 2 
11 " 315 97 100 77 16 2 
12 " 320 99 100 77 14 3 
13 " 325 100 100 76 10 4 
14 1:1 291 50 65 91 7 1 
15 " 300 66 79 89 8 1 
16 " 305 79 91 89 7 1 
17 " 310 87 95 86 6 2 
18 " 315 95 100 84 9 2 
19 " 320 98 100 80 10 3 
20 " 324 99 100 81 10 4 
21 1.5:1 300 74 88 92 3 3 
22 " 305 82 93 92 3 3 
23 " 310 92 97 88 3 3 
24 " 315 97 100 88 4 3 
25 " 320 99 100 84 5 4 
26 " 325 99 100 84 6 5 
______________________________________ 
.sup.a Data is basis GC analysis of crude reactor effluents. Selectivitie 
are approximate Area % on a water and feed free basis. 
.sup.b Adducts are moles EO/mole piperazine. 
.sup.c Temperature in degrees Centigrade. 
The following trends are discernable from the data presented: 
1. BisHEP is more reactive than HEP. 
2. Increased EO content of the feed decreases the amount of PIP in the 
reactor effluent. 
3. In all cases N-ethyl piperazine byproduct formation increases with 
increased temperature of reaction. 
4. In all cases TEDA yield is optimized near 320.degree. C. where 
conversions approach 100%. 
C. Bis-N-Hydroxyethyl Piperazine (BisHEP) Feedstock 
Recrystalized BisHEP was evaluated as a feedstock for the preparation of 
TEDA using the equipment and procedures of I. As discussed above, an 
aqueous solution (20 wt. %) was fed to the reactor. The results are 
presented in Table III. 
TABLE III.sup.a 
______________________________________ 
TEDA via BisHEP 
Ex. TEMP.sup.b CONV. TEDA PIP EtPIP 
______________________________________ 
27 300 70 90 2 3 
28 305 74 90 2 3 
29 310 85 90 3 3 
30 315 88 87 3 4 
31 320 83 92 3 2 
32 325 98 83 5 5 
______________________________________ 
.sup.a Data is basis GC analysis of crude reactor effluents. Selectivitie 
are approximate Area % on a water and feed free basis. 
.sup.b Temperature in degrees Centigrade. 
In contrast with data presented in Table II, BisHEP conversion was only 98% 
at 325.degree. C. This apparent decrease in activity is probably due to 
inaccuracies in the G.C. analysis. In cases where BisHEP concentrations 
start low, for example, a 75% conversion may drop the concentration of 
BisHEP below detectable levels resulting in a calculated 100% conversion. 
This is probably the reason for apparent high activity in the low EO/PIP 
adducts. 
Using the same procedure as outlined above, a crude BisHEP feedstock was 
tested as described above in I. The feed was prepared as a 1:1 EO/HEP 
adduct; this is expected to be equivalent to a 2:1 EO/PIP adduct. At 
320.degree. C., conversion was about 96% with a selectivity of 89% to 
TEDA. 
D. Ethoxylated Crude Polyethylenepolyamine Feedstock 
A blend was prepared to simulate a crude aminoethylethanolamine (AEEA) 
material obtainable by flashing material from a residue stream of an 
ethylenediamine plant. The composition of this blend was (by weight) 88% 
AEEA, 4% DETA, 4% AEP, and 4% HEP. This blend was then ethoxylated with 
various equivalents of EO. The feed consisted of a 20 wt. % aqueous 
solution of this ethoxylated material and the runs were made as described 
in I. The selectivity data using this feed is presented in Table IV. 
TABLE IV.sup.a 
______________________________________ 
TEDA via Ethoxylated Amine C-1 
Ex. Adduct Conv.sup.c 
TEMP.sup.b 
TEDA PIP EtPIP 
______________________________________ 
33 1:1 &gt;95% 320 61% 10% 9% 
34 1:1 &gt;99% 330 70% 9% 15% 
35 1.5:1 &gt;83% 330 63% 5% 5 
______________________________________ 
.sup.a Data is basis GC analysis of crude reactor effluents. Selectivitie 
are approximate Area % on a water and feed free basis. 
.sup.b Temperature in degrees Centigrade. 
.sup.c Conversions are approximate and based upon the HEP and BisHEP 
content. 
It is readily obvious that the selectivity to TEDA using this feed mix is 
considerably lower than the other alternatives discussed above. However, 
this route uses a relatively inexpensive feedstock. 
E. Ethoxylated Ethylenediamine (EO/EDA, 2:1) Feedstock 
In another variation, a 2:1 (m/m) ratio of EO/EDA was used as the source of 
TEDA precursor. This material should be similar to the ethoxylated crude 
AEEA (Amine C-1 of Example B). This run was performed as described above 
in I using a 20% solution as feed. The temperature required for near 
complete conversion was 340.degree. C. as compared to about 320.degree. C. 
for the HEP feedstocks. The selectivity to TEDA at this temperature was 
60%. The major byproducts were still PIP and EtPIP. 
F. Diethanolamine (DEA) Feedstock 
Diethanolamine was used as a feed for the preparation of TEDA. The first 
step involves a bimolecular cyclization to BisHEP. The BisHEP then reacts 
as in the above examples to give TEDA. The yield in this approach is very 
poor due to losses from side reactions. This suggests that the initial 
formation of BisHEP exhibits poor selectivity since the subsequent 
cyclization of BisHEP goes in high selectivity. At 320.degree. C., DEA 
coversion was &gt;95%. Selectivity to TEDA was only 40%. 
Long-term Catalyst Stability Evaluations 
G. HEP Process 
A 1000 hour catalyst evaluation was run with 20% (v/v) aqueous HEP to 
determine the activity/selectivity stability over prolonged use. Operation 
of the run was identical to that described above in I. In this experiment 
the initial temperature required for 99% HEP conversion was 330.degree. 
C.; selectivity to TEDA was 74%. After 800 hours on-stream, conversion was 
99% with a selectivity to TEDA of 72% at an operational temperature of 
340.degree. C. After 1000 hours on-stream, conversion was 97% with a 
selectivity to TEDA of 67% at an operation temperature of 345.degree. C. 
This represents a modest loss in activity and selectivity occuring in the 
last several hundred hours of operation. Regeneration of the catalyst was 
not attempted. 
H. Ethoxylated Piperazine (EO/PIP, 1.5:1) Feedstock 
A 4:1 aqueous dilution of crude HEP was prepared for this evaluation. The 
material contained 25% water presumable from the use of piperazine 
eutectic formed in the preparation of this adduct. This feed contained 25% 
PIP, 61% HEP, and 14% BisHEP on a water-free basis and run in the manner 
described above in I. As seen in runs using pure HEP, there is a net 
production of piperazine. Initially, on a piperazine feed-free basis, the 
selectivity to PIP, EtPIP, and TEDA was 7%, 11%, and 80%, respectively; 
99% Conversion was obtained at 333.degree. C. After 1000 hours, 99% 
conversion was obtained at 340.degree. C.; selectivities were 4%, 19%, 
69%, respectively. 
I. Hydroxyethyldiethylenetriamine 
A 20% aqueous solution of crude hydroxyethyldiethylenetriamine was 
evaluated in the manner described above in I. The run was made at 
310.degree. C. at atmospheric pressure with a LHSV of 1. On a feed-free 
basis, the selectivity to products was: 
AEP--49.6% 
PIP--11.6% 
TEDA--16.1% 
Conversion of the feed was 95.6%. 
At 290.degree. C., feed conversion was 65.8% and selectivities were: 
AEP--65.3% 
PIP--3.8% 
TEDA--7.3% 
The foregoing examples are given by way of illustration only and are not 
intended as limitations on the scope of this invention, as defined by the 
appended claims.