Alumina activated with anhydrous hydrogen fluoride as a cracking catalyst for gas oil
by Harry A Herzel
A THESIS Submitted to the Graduate Committee in partial fulfillment of the requirements for the
degree of Master of Science in Chemical Engineering
Montana State University
© Copyright by Harry A Herzel (1949)
Abstract:
The purpose of this work was to evaluate alumina activated with anhydrous hydrogen fluoride as a
cracking catalyst for a virgin gas oil.
Preliminary investigation showed that at a liquid space velocity of 1 volume gas oil per volume catalyst
per hour, on-stream cycle time should be approximately 30 minutes.
These conditions were held throughout the investigation.
Catalytic cracking runs were made over a range of the temperatures to determine the optimum cracking
temperature.
The temperature range was duplicated with runs using unactivated catalyst to obtain a standard of
comparison.
It was concluded that under the conditions of this investigation the gasoline yield, ultimate yield, and
per cent conversion is greater for hydrogen fluoride activated catalyst than for untreated alumina at all
temperatures studied; and that the optimum cracking temperature of the catalyst was 475 ± 5°C, The
data obtained showed that the gas yield from the Reaction increased from 0,38 weight per cent to 4.0
weight per cent when the activated catalyst temperature was increased from 406°C. to 502°C,, anti
from 0,20 weight per cent to 3=1 Weight.per cent when the unactivated catalyst temperature was
increased from 404°C. to 497°C, The data also showed that the motor octane number of the gasoline
samples obtained from the activated catalyst increased as the cracking temperature was increased.
ALUMINA ACTIVATED WITH ANHYDROUS HYDROGEN
FLUORIDE AS A CRACKING CATALYST FOR GAS OIL
by
HARRY A e HERZEL
A THESIS
Submitted to the Graduate Committee
in
partial fulfillment of the requirements
for the degree of
Master of Science in Chemical Engineering
at
Montana State College
Approved:
I Charge of" Major^Work
1!''rMlulJ vi,,nfr
'm in ; : !
■
.
Bozeman, Montana
May, 1949
2
TABLE OF CONTENTS
Page
A b s t r a c t ...............................
,
4
I
I n t r o d u c t i o n ..........................
.
5
II
Equipment, Methods, and Compounds. . . .
A. Equipment ........... . . . . .
B . Methods ........................
C . Materials ......... . . . . . .
12
15
III
Sample Calculations.................
16
IV
R e s u l t s ..................
19
V
C o n c l u s i o n s ...........................
23
VI
Acknowledgment
24
VII
Literature Cited ........................
25
VIII
Appendix .........
26
. .
. . . . . . . . . . .
8
8
Table I - Gas Oil A n a l y s i s .............
27
Table II - Catalytic Cracking of Gas Oil
with On-Stream Cycle Longer than 30
Minutes and Activated Catalyst. . „
28
Table III - Catalytic Cracking of Gas Oil
with an On-Stream Cycle of 30 M i n ­
utes and Activated Catalyst . . . .
29
Table IV - Catalytic Cracking of Gas Oil
with an On-Stream Cycle of 30 M i n ­
utes and Unactivated Catalyst . . .
30
Table V - Sulfur Content and Octane
R a t i n g ........................ ..
31
Figure I - Diagram of Reaction System.
Figure 2 - Effect of Temperature on
Gasoline Yield (Per Cent Gasoline
on Gas Oil C h a r g e d ) ...............
92548
.
32
33
3
Figure 3 ~ Effect of Temperature on Gasoline
Yield (Per Cent Gasoline on L i q u i d '
34
Figure 4 - Effect of Temperature On G^sbline
Yield (Per Cent- Gasoline on ProductP lU S Gas) O o e e io o o o e
35
Figure 5 - Effect of Temperature on Gdisoline
Yield and Per Cent Conversion (Pdr cent
Gasoline.on Gas Oil Charged),
36
Figure 6 - Effect of Temperature'On Gasoline
Yield and Per Cent Conversion (Per cent
Gasoline on Liquid Product) . ...........
37
Figure' 7 - Effect of Temperature On Gasoline
Yield and Per Cent Conversion (Per Cent
Gasdlirie on Product Plus Gas)
38
Figure 8 - Gas Production as aJFunetion of
Temperature * , , , , # , , @ 0 , 0 0 0 ,
3.9
Figure 9 - Octane Numbers and Sulfur Content
as a Function of Temperature,
40
4
ABSTRACT
The purpose Of this work was to evaluate alumina acti­
vated with anhydrous hydrogen fluoride as a cracking catalyst
for a virgin gas oil.
Preliminary investigation showed that at a liquid space
velocity of I volume gas oil per volume catalyst per hour,
on-stream cycle time should be approximately ■30 minutes.
These conditions were held throughout the investigation,
.Catalytic cracking runs were made over a range of the
temperatures to determine the optimum cracking.temperature.
The temperature range was duplicated with runs using unacti­
vated catalyst to o b t a i n s standard of comparison.
It was concluded that under the conditions of this in­
vestigation the gasoline yield, ultimate yield, and per cent
conversion is greater for hydrogen fluoride activated catalyst
than for untreated alumina at all temperatures studied $ and
that the optimum cracking.temperature.of the catalyst was
4?5 ± 50C,
■The data obtained showed that the gas yield from the
Reaction increased from.0*38 weight per.cent.to 4,0 weight
per cent when the activated catalyst temperature was increas­
ed from- 4 0 6 % , to 5020C 0, and from 0,20 weight per cent to 3 =1
Weight.per cent when the unactivated catalyst temperature was
increased from 404c’C , to 497°Ce
The data also showed that the
motor octane number of the gasoline samples obtained from the
activated catalyst increased as the cracking temperature w a s "
increased,
-
5 .
I, INTRODUCTION
The chief function of a cracking catalyst is its acceler­
ation of bond fracture„
It is generally understood that the-
acceleration is hot random but selective to certain bonds.
The work of Greensfelder«, V o g e 5 and Good. (6 ) brought out this
selection of rupture„
1®
Their findings were as follows;
Paraffins are cracked preferentially at those links
which yield fragments of three or more carbon atoms»
Shorter chains' tend to crack near the center carbon
atom and longer chains tend to crack simultaneously
in several places,
2„
Naphthenes tend to give three carbon atom chains.
Cracking may take place in both the ring and side
chain*
3« . In substituted aromatics, the link to the ring is
sheared off to leave a bare aromatic,
4,
Olefins are attacked in much the same manner as para­
ffins , except more readily„
Typical conclusions from catalytic cracking investigations
were presented by McGrew (10) who use ”Tonsil"
(a siliceous
cracking catalyst) with varying amounts of potassium hydrogen
phosphate to obtain a yield of 30*6 vol* per cent gasoline at
0*5 per cent phosphate from gas oil.
Lee and Thomas (9) con­
cluded that §l zirconium oxide activated silicate would yield
28*7 v o l o per cent of 79*7 octane number gasoline from gas oil*
6
The catalyst quality is one'factor that will make a cat­
alytic process a success or a failure„
Conn and Connolly (4)
showed that surface area, carbon forming tendency, and gas
forming tendency had a profound effect- on gasoline production.
Although the quality of surface area is fixed for any cata­
lyst, the gas forming and carbon forming tendencies are prim­
arily affected by, pressure and temperature,
, Pressure, contact time, and temperature are probably the
most important variables in any catalytic process.
Since the
conversion of a hydrocarbon feed stock varies with catalyst
temperature, an exploration of the temperature variable should
be included in the study of a catalytic process.
Although it
is nearly impossible to determine the temperature involved on
the catalyst surface during cracking, an average temperature
obtained by thermocouples inserted into the catalyst bed is
usually significant for comparative purposes.
The catalyst used in' this investigation-was alumina pel­
lets impregnated with anhydrous hydrogen fluoride,
The cataly­
tic properties of hydrogen fluoride have been ,investigated for
allied operations.
Kuhn (8 ) reformed narrow-boiling branched
chain gasoline hydrocarbons to a gasoline fraction of desired
distillation characteristics by contact with hydrogen fluoride
of at least 90 per cent concentration,
Gibson (5) used hydro­
gen fluoride in a combination process of alkyIqtion and isomer­
ization of normal butane, and Clark (3) reported the use of
7
hydrogen fluoride as a catalyst in the alkylation of isobuty­
lene „
To obthin a comparison with results obtained with the
hydrogen fluoride impregnated alumina, cracking runs were made
with untreated alumina pellets„
These are referred to as
"unactivated catalyst" runs in this work.
The purpose of this thesis is to evaluate anhydrous hydro­
gen fluoride activated alumina as a cracking catalyst for a
virgin gas oil.
This investigation will report optimum crack­
ing temperature, gasoline yield, and gasoline quality in terms
of octane number and sulfur content.
No attempt was made to determine optimum conditions of
pressure or space velocity in the cracking system.
The space
‘
velocity was arbitrarily held at approximately I volume per
volume of.catalyst per hour and at one atmosphere of pressure.
The average barometric pressure during this study was approxi­
mately 635 mm. of Hg..
The investigation does not include, a report of carbon lay
down, optimum on-stream time or catalyst life.
The catalyst
was apparently unaffected by burnoffs carried out below the
sintering temperature of alumina.
All per cents reported in the results are given as weight
per cent.
•8
II. EQUIPMENT, METHODS M D MATERIALS
A.
Equipment
The cracking unit comprised the following equipments
a 1000 ml graduated separatory fupnel, a bellows pump, an
electrically heated reactor, a water cooled condenser, a dry
ice condenser, Erlenmeyer receivers, a gas m e t e r , a Harvard
type triple-beam balance, Powerstats, a Brown potentiometer,
arid iron-constantan thermocouples.
Equipment for the rectification of the cracked product
was as follows:
a precision rectification column, a round
bottom distilling flask, a distilling flask heating mantle.,
a reflux condenser, dry ice traps, thermometers, Powerstats,
and a side arm vacuum flask.
Equipment exactly as described
by the A.S.T.M. Standards (I) was used for sulfur determin­
ations by the lamp method.
The 1000 ml graduated separatory funnel, which acted as
the gas oil charge reservoir, was connected to a Merkle-Korff
bellows pump with 1/4 inch neoprene tubing.
The bellows pump
charged the feed stock to the reactor through three feet of
1/4 inch annealed copper tubing.
The reactor body was made of a three inch black standard
mild steel pipe 24 inches long with standard pipe threads at
both ends.
The top of the reactor was fitted with a three
inch flange, a three inch short, nipple and a three inch stand­
ard cap.
Changing the catalyst was simplified by opening the
9
reactor at the flange rather than at the cap,
A 1/2 inch hole was drilled into the cap and threaded to
take a 1/2 inch standard nipple and a 1/2 inch standard cross.
Two openings of the cross were closed with plugs and the third
outlet was fitted with a 1/4 inch by 1/2 inch reducer.
this reducer a copper tubing fitting was screwed.
Into
This fitting
held the gas oil feed line from the bellows pump.
The bottom of the reactor tube was fitted with a three
inch standard pipe cap.
A 1/2 inch hole was drilled into the
cap and threaded to take a 1/2 inch standard nipple and a
1/2 inch standard sleeve assembly.
The sleeve opening was
fitted with a 1/4 inch by 1/2 inch reducer.
Into the reducer
was screwed a copper tubing fitting which held a 1/4 inch
copper tube approximately eight inches long.
The copper tube
led to a glass bulb type water condenser 10 indies long and a
dry ice condenser connected in series.
A diagram of this
equipment is shown in Figure I.
Three 1/8 inch standard black pipes, 4-3/4 inches long
and sealed at one end, were inserted through holes drilled
through one side of the reactor.
These pipes, which were
welded to the reactor so that the sealed ends were approxi­
mately at the reactor center line, acted as thermowells, and
were so located that they would give the temperature at the
t o p , middle and bottom of the catalyst bed.
The reactor body was wound with two layers of asbestos
10
tape to Insulate the heating coil.
This heating coil which
•
.
’
-
was connected to a 220 volt Powerstat, was. made of 75 .f$et of
Nichrome wire rated at '1,079 ohms per foot.
of asbestos tape were wound over the coil.
Two more layers
Next, two lengths
of Nichrome wire 33 feef IPn S and rated at 1,079 ohms pqr foot
were wound around the Reactor so. that one wire controlled the
preheat section and the second controlled the catalyst section.
The !-ends of these windings were connected to 110 volt Pgwerstats.
Magnesia bgts were then wired to the reactor bo^y and
covered .with asbestos mud j;o provide the necessary insulation
against heat loss.
The reactor was filled with Berl saddles to the undersur­
face of the lower thermocouple.
Nine hundred milliliters of 1/8
inch alumina pellets were placed on top of the Berl saddle lay­
er and the remaining space above filled with more Berl saddles.
The distillation cpltunn was constructed of three lengths
o^. .glass tubing arranged concentrically and held in position by
means of asbestos t^pe and glue.
with 1/4 inch glass helices.
The inner tube-was;p a c k e d ■
A thermometer was attached to
the outside of. the inner tpbo near the center,. The middle .
tube was wound with Nichrome w i r e 'to provide heat ^
The amount
offbeat supplied was controlled by a Powerstat * • The outer.tube
provided added insulation and also protected the Nichrdme wind­
ing .
The overall height of the column was 24 inches.
height of the packing was 22 inches.
The
11
The refiux condense,]? was ^attached to the top of the column
by a 29/42 standard tapered groupd glass joint.
A second ther­
mometer Was attached t 6 the refluijc cpndensbr to measure vapor
temperature.
I
: - The potentiometer used was manufactured by the Brown
Company-and could be used to record temperature up ?to 12009c.
This-'..instrument gave readihgs in miliiVolts^ which were- convert­
ed to degrees Centigrade by means of a table provided by the
manufacturer*
%
The Powerstats were small-autotransformers manufactured
by ,Superior Electric Company . jThe. ,maximum input .w a s ..7-1/2
amperes at H O
volts and five amperes at 220 vol t s <
The out­
put,ranged from 0 to 135 volts for the H O volt Powers tat. and
0 to 235 volts ,for the 220..VolttPowerstat«
.
.-
-The. gas meter used was .a three liter "Precision" Wet Test
metero
12
Bo
1«,
Methods
Activation of the Alumina Pellets s
The manner of catalyst activation was similar to that
outlined by Berg (2).
for two hourso
The-alumina pellets were dried at 250°C„
After the drying period, the reactor was allow­
ed to cool to room temper&tur^„
Anhydrous.hydrogen fluoride
was then passed- through the catalyst for two hours 9 and for
another hour while the catalyst temperature was being raised
to 4000C „
The catalyst was- then purged with nitrogen for
about fifteen minutes to sweep out the excess hydrogen fluor­
ide o
The hydrogen fluoride leaving the reactor was bubbled
through kerosene and out a blowdown line*
2*
Making the Cracking R u n s :
The reactor was heated until the middle thermocouple was
approximately five degrees above the desired temperature»
The
air in the reactor was then displaced by a nitrogen purge last­
ing approximately fifteen minutes«
The feed lined was connect­
ed immediately after the nitrogen purge and the bellows pump
started.
Dry ice was placed in the condenser and initial
reactor temperature was recorded„
Readings of the gas meter?
charge reservoir, and the three thermocouples were taken at
five minute intervals.
The flask containing the product was
removed, weighed, and placed in a refrigerator maintained at
=400C to minimize loss of the lighter hydrocarbons.
The re­
actor was allowed to stand until the gas meter stopped
13
recording gas flow.
This final reading gave the total gas
produced during the on-stream cycle.
Upon completion of the
run, the reactor was again purged6with nitrogen until all hydro­
carbon
vapors were removed.
The carbon laydown was then
burned off the catalyst by passing a stream of air through the
reactop.
The temperature of the burning zone was maintained
at approximately 500 0C . during the regeneration.
The same pro­
cedure was utilized for the control runs.
3c
Measuring Gas Density;
A nineteen liter bottle filled with water was connected
to the downstream side of the gas meter during the cracking
cycle„
As the gas left the m 6ter it was allowed to displace
the water until the bottle completely drained.
Weight of the
bottle plus a i r , the bottle plus gas, and room temperature were
recorded.
4 0.
Distillation of Reaction Products;
The charge was placed in a distillation flask which was
surrounded by a heating mantel.
The Powerstats were adjusted
so that the column would flood and completely wet the packing.
Hydrocarbons that did not condense on the cold finger were led
to a dry ice trap.
The heat input was then reduced until
flooding stopped and the column was permitted to operate at
total reflux for one hour.
The reflux ratio was then set at
about 5 sl and all products boiling up to the recorded end
points were taken off as the gasoline sample.
The weights of
14
residue and gasoline sample were then recorded.
5o
Sulfur Determination of Gasoline Product %
The sulfur determination was made exactly as prescribed
by the A.S.ToM. Standards.
To check technique of operation,
a determination of the sulfur content of a known solution was
madeo
This sample was made from a mixture of thiophene and
thiophene free benzene„
60
Preparation of Gasoline Product for Octane Bating %
The gasoline samples had to be neutralized because ok the
acidic nature of the catalyst used in this investigation. .
This was accomplished by washing the gasoline with a 10 per
cent sodium hydroxide solution.
was approximately three minutes.
Contact of sample with base
15
C.
Materials
No attempt was made to purify any of the reagents used*
Compound
Grade
Source
Benzene
Thiophene Free
General Chemical C o 0
Sodium Hydroxide
Electrolytic C «P,
Fisher Scientific Co,
Hydrogen Peroxide
C,P,
Fisher Scientific Co,
Methyl Bed
Analytical
Fisher Scientific Co,
Thiophene
Synthetic
Eastman Kodak Co,
Nitrogen
95% water pumped
The Matheson Co,
Anhydrous Hydrogen ■
Fluoride
Alumina Pellets,
1/8 inch diameter
The Matheson Co,
Harshaw Chemical Co,
The material charged to the reactor was a virgin atmos­
pheric gas oil from Elk Basin and Frannie, Wyoming, crude .
oils in approximately 70 - 30 ratio,
A laboratory analysis
of this material is given in Table I,
^
1IZJlaI/-!
I 11,'I'/'r
16
III.
SAMPLE CALCULATIONS
The sample calculations are based on Eun #13 because
optimum gasoline yield was attained here.
Calculations on
a:ll runs were made by exactly the same methods.
A.
Average Gas R a t e :
During Run 1 3 ? as for each run made, the gas meter was
read in liters every five minutes.
From these readings the
quantity of gas passing through the meter for each five min­
ute interval was calculated.
By averaging these values and
dividing by five minutes, the gas rate in liters per minute
was obtained.
Ne^t the total gas oil charged was divided, by
the on-stroam time to obtain grams of gas oil charged per
minute.
Dividing the former by the latter and multiplying
by 1000 gave the average gas rate in c c ’s of gas produced per
gram of gas, oil charged.
B.
Calculation of Liquid Snace Velocity:
In each run the space velocity was held at, I cc liquid
gas oil charged per cc catalyst per hour.
C.
' Density of Gases Produced by Cracking:
Weight of 19.1 liter flask plus air
6248 gms.
Weight of 19.1 liter flask plus gas
6236 gms.
Difference
'
12 gms.
Density of air at 25°C. and 640 mm of Hg. pressure is
0.99748 grams per liter (7).
Therefore 19.1 liters times
0.99748 grams pdr liter less 12 grams yields 7»0^ grams of gas
T-
17
contained in the f Iask 0
Finally the density of the gas is
calculated as 7*05 divided by 19 »I which equals 0»370 grams
per liter*
D0
Calculation of Yields:
The yield of cracked product is given in weight per cent
and based on the grams of gas oil charged.
The yields of resi­
due and gas and losses from rectification are given in weight
per- cent
and based on the grams of gas oil charged.
Thus for
R u n 13:
Cracking
Grams
Gas Oil charged to Reactor
395
Liquid Product
328.9
8.0
Gas
Losses
Weight Per Cent
83.3
2*0
'
5 8 .1
14*7
200.4
50.8
Rectification
Residue
Gas and losses •
14.5
3.6
The gasoline product was calculated with three different
basis, namely 5 by grams gas oil charged, by grams liquid pro­
duct from the reactor, and by grams liquid product plus grams
gas produced by cracking.
T h u s , for Run 13:
Grams
Gas Oil Charged
395
Liquid Product from Reactor
328.9
Gas Produced on Cracking-
8.0
18
Gasoline Produced
114 c0
Basis of Calculation
Per Cent Gasoline
Gas Oil Charged
28.8
Liquid Product
34.7
Liquid Product Plus Gas
33.8
E0
Calculation of Per Cent Ultimate Y i e l d :
For Run 13, 328*9 grams of liquid product less 114,0
grams of gasoline yields 214.9 grams of unconverted gas oil.
Therefore, the 395.0 grams of gas oil charged less 214.9 grams
of unconverted gas oil yields 180.1 grams of gas oil converted
to gas, carbon, gasoline, and losses.
Finally 114.0 grams of
gasoline divided by 180.1 grams of converted gas oil times 100
gives an ultimate yield of 63*3 per cent.
F.
Calculation of Per Cent Conversion on Charge:
For Run 13? per cent conversion of gas oil to gas, coke,
and gasoline may be obtained by subtracting 50.8 per cent resi
due from 100 per cent.
This method of calculating per cent
conversion includes losses from cracking and distillation.as
conversion
19
IV.
RESULTS
Although optimum on-stream time was not investigated,
an initial run was mac}e to determine how activation dropped
off with cycle time.
This run was made for a period of 146
minutes at approximately 400°C.
Results of data taken during
the first 73 Ainutes of operation appear in Table II as Run 5®
Results of data taken during the last 73 minutes appear in
Table II as Run 6.
From these results it is possible to com­
pare gasoline yield for the first 73 minutes with that obtained
from the last 73 minutes.
During R un 5» 12.3 per cent of th6
charge was converted to.gasoline while Run 6 yielded 4.53 per
cent.
In Run 7? the temperature was increased to 501°C .9 and
the reactor was charged for 67 minu t e s . .This run converted
23.6 per cent of the gas oil charged to gasoline.
These results showed that as the on-stream time increased
the gasoline yield decreased.
Therefore, a 30 minute on­
stream cycle was arbitrarily chosen for the investigation.
These results also showed that increasing the catalyst temper­
ature w o u l d .increase the gasoline yield.
The remainder of the
investigation was concerned therefore with finding that temper­
ature which would give a maximum yield of gasoline.
Table III tabulates the results of cracking gas oil with
an anhydrous hydrogen fluoride activated alumina catalyst.
The
runs are arranged in the order of increasing temperatures,
The
results show that as temperature increases, the per cent
gasoline yield increases= until the catalyst temperature
reaches 475°Co) then begins to decrease.
A graphical repre­
sentation of this is given in Figure 2 where per cent gasoline
yield based on gas oil charged and per cent ultimate yield are
both plotted as a function of temperature0
• Figure 3 shows that a maximum ultimate yield of 63 .3 per
cent is reached at 4750Co) for the activated catalyst.
This
plot does not show whether or not a maximum gasoline production
based on per cent of liquid product had been reached at 4750G OSI
since the highest reaction temperature investigation gave a
gasoline yield which fell.on the plateau which began at approx­
imately 475°Co
1
The gasoline yields were also calculated on the .basis of
liquid product plus gas because the method of calculating gas­
oline yield based on liquid product alone does not consider gas ■
oil converted to gas by the catalyst, and the result of this
I
calculation plotted in Figure 4 shows that a maximum gasoline
yield was obtained at 475°Cc
The calculated results given in Table III include per
cent conversion of gas oil to carbon, gas, losses, and gaso­
line.
Figure 5 shows how both gasoline yield based on gas oil
charged and per cent conversion varied with catalyst temper­
ature.
This graph shows that at approximately 475°C= a maxi­
mum gasoline yield of 28.8 weight per cent was obtained with
the activated catalyst.
21
Figure 6 shows how both gasoline yield based on liquid
product and per cent conversion varied with catalyst temper­
ature „
The per cent gasoline yield obtained from, the acti­
vated catalyst increased rapidly until a catalyst temperature
of approximately 4 7 5 ° C . was reached and then remained nearly
constant up
to the highest catalyst temperature investigated«
Figure 7 shows how both gasoline yield based on liquid
product plus gas obtained from the reaction and per cent con­
version varied with catalyst temperature.
This plot shows
that a maximum per cent gasoline yield of 3 3 c8 weight per cent
was obtained at a catalyst temperature of 475°C. with the
activated catalyst.
Figures 5? 6 and 7 also show that the per cent conversion
of gas oil increased as the catalyst temperature was increased.
The results of catalytic cracking of gas oil with un­
treated alumina pellets are tabulated in Table I V .
These re­
sults are plotted on Figures 2, 3» 4, 5? 6 and 7 so that the
effect of the hydrogen fluoride activation on the gasoline
yield may be compared.
It should be noted that the activated
catalyst curves are similar to the unactivated catalyst curves
in shape and that both show the same approximate temperature
where maximum ultimate yield was attained.
Figures 2 ? 4 9 5
and 7 show a maximum gasoline yield for both activated and
unactivated catalyst at approximately 475°C.
Tables III and IV show that the per cent gas produced by
22
the activated, as well as the unactivated catalyst increased
as the temperature increased,
A plot of these results,
Figure 8, shows that from 410°Ce to 480 ° C ,, the per cent of
the charge converted to gas by the activated catalyst is less
than the per cent converted by the unactivated catalyst.,
which indicates a low gas forming ability for the activated
catalyst in this temperature range„
In Table V are tabulated the results of the sulfur and
octane number ratings of the gasoline samples taken from Runs
9, 11, 13 and 15 of Table III,
The octane numbers showed a
tendency to increase as the catalyst temperature, was increased
The sulfur contents, of the gasoline samples went through a min
imum value of 0,384 per cent at 4 5 0 ° C ,
A plot of octane
number as a function of reaction temperature and sulfur con­
tent as a function of the same variable is given as Figure 9»
23
Vo
CONCLUSIONS
The following conclusions may be drawn concerning the
cracking of a virgin gas oil with the hydrogen fluoride acti­
vated catalyst:
1«,
Gasoline yield and per cent convers-ion- is greater
for hydrogen fluoride activated alumina, compared
with untreated alumina, at all temperatures
studiedo
2o
At one atmospherecf pressure and a space velocity of
one volume of charge per volume of catalyst per
hour, gasoline yield and ultimate gasoline yield
reach a maximum at a cracking temperature 475 t 5°Co
The per cent conversion of gas oil increases with
catalyst temperaturee
.3„
The per cent £as yield from the reaction increased
when the catalyst temperature was increased,
4o
The motor octane number of the gasoline samples
obtained with the activated catalyst increased as
the cracking temperature was increased.
24
VIc
ACKNOWLEDGMENT
The author acknowledges with thanks the courtesy of the
Carter Oil Company who furnished the gas oil u.sed in this
investigation, and of the Phillips Petroleum Company for
determining the octane numbers of the gasolines®
25
VIIo
LITERATURE CITED
(1)
AoSeTol. Committee D-2, nP e t r o l e m Products and
Ltibricantsn 9 D90-41T. 272-276 (1941).
(2)
B e r g 9 'I., Sumner9 G. L o 9 and Montgomery9 C e W o 9
(To Gulf Research and Development Co.): U.So Patent
2,397,639 (April 2 ? 1946).
(3)
Clarke9 L. A 0 ? (To The Texas Go.); U eS. Patent 2 94 0 3 9501
(July 9, 1946).
...............
(4)
C o n n 9 -M. Eo9 and Connolly, G. Co, "Testing of Cracking
Catalysts", I n d 0 E n g 0 C h e m .? 3 9 , 1138-1143 (1947)*
(5)
Gibson9 J 0 D 0, (To Phillips Petroleum C o . ) ; U.S. Patent
2,347,317 (April 24, 1944).
(6)
Greensfelder, B 0 S 0, V o g e 9 Ho H., and Good, G. M.,
"Catalytic Cracking of Pure Hydrocarbons", In d 0 E n g .
C h e m oa 3 Z 9 1168-1176 (1945)o
(7)
Hodgman, C 0 D . , "Handbook of Chemistry and Physics",
Chemical Rubber Publishing Co. Twenty-Fifth Edition,
(1941).
(8)
Kuhn,. Co S 0 J r 0, (To Socony-Vacuum C o . , Inc.); U 0S 0
Patent 2,403,929 (July 16, 1946).
(9)
L e e 9 E0 C 09 and Thomas9 C 0 L 0, (To Universal Oil
Products Co.); U 0S 0 Patent 2,406,613 (August.27, 1946).
(10) McGrew, E* H . , (To Universal Oil Products C o 0); U 0S.
Patent 2,377,093 (May 20, 1945).
26
VIII APPENDIX
Page
A0
Table I - Gas Oil Analysis » » o , e . = <> » „ „ .
27
B0
Table II - Catalytic Cracking pf Gas Oil With OnStream Cycle Longer than 3<? Minutes and Acti­
vated Catalyst 0 * * * * * * * * 0 * * * * « *
2’
6
Table III - Catalytic Cracking of Gas Oil with an
On-Stream Cycle of 30 Miputes arid Activated
Catalyst* * * * * 0 * * * * * 0 * * * 0 0 @ %
29
Table IV - Catalytic Cracking of Gas Oil with an
On-Stream Cycle of 30 Minute^ and Unaetivated'
Cataly s t 0 * 0 0 0 0 © © 0 0 :« * * * 0 0 0 *0 0
30
Eo
Table V - Sulfur Content and Octane Ratings*
* * * *
31
Fo
Figure I - Diagram of Reaction Systep0. * * * * „ „ *
■■ i ■
: .:
Figure 2 - Effect of Temperature on Gasoline Yield
(Per Cent Gasoline cn Gas Oil Charged)-» „ „ „ »
32
33
F i g u r e -3 - Effect of Temperature on Gasoline Yield
(Per Cent Gasoline on Liquid Product) 0 0 „ e »
34
Figure 4 - Effect of Temperature on Gasoline Yieldz(Per Cent Gasoline on Prodtict Plus Gas) » » * «
35
Go
Ho
Io
J0
Figure 5 ~ Effect of Temperature on Gasoline Yield and
Per Cent Conversion (Per Cent Gasoline on Gas
O i l .Charged)© « $ » * © © © © © © © © © © © © © 36
Figure 6 - Effect of Temperature on Gasoline Yield and
Per Cent Conversion (Per Cent Gasoline on Liquid
Product) 0 0 0 0 0 * 0 0 0 0 0 0 0 0 0 0 0 0 0 0
37
Lo
Figure 7-= Effect of Temperature on Gasoline Yield and
Per Cent Conversion (Per Cent Gasoline on
Product Plus Gas) © © © © » © © © © © © © ©o' © 38
Mo
Figure 8 - Gas Production as a Function of
Temperature o © © © © © © © © © © © © © © © © ©
39
Figure 9 - Octane Numbers and Sulfur Content as a
Function of Temperature © © * © © © * © © © « ©
40
No
27
TABLE I
Gas oil analysis as given by the Carter Oil Company,
Billings, Montana.
T ime:
Date:
10 A .M„
8/12/47
Gravity
Distillation
Product:
Source:
0AoP.!.
I.B.P.
5$
10$
20#
30$
40$
50$
60$
70$
80$
90$
27.9
524°F
558
570
580
588
601
614
628
648
Sulfur, Weight Per Cent 1.56
676
714
Per Cent Recovery
95$ at 730°F
Viscosity
52„6 S e c . at
Remarks:
2$ at 550°F
71$ at 650°F
Tested by CS and CRS
Gas Oil
No. 5 Unit #4 Stream
IOO0F. S.U.
28
TABLE II
Catalytic Cracking of Gas Oil with On-Stream Cycle Longer than
30 Minutes and Activated Catalyst
Run No.
Catalyst, cc.
5
800
6
800
7
900
I
I
I
CRACKING:
Liq. Sp. Vel., hr.-1
Gas Oil Cracked by Catalyst
Before Run began, grains
Temp., 0C
On-Stream Cycle, mins.
Ave. Gas Rate, cc. gas/gram charge
Total Gas, Liters
Charge, grams
Product, grams
% Liquid Product
Gas, grams
dJo Gas
Carbon and Losses, grams
tJ0 Carbon and Losses
0
415
73
24.8
17.0
869
810.9
93.3
6.3
0.73
51.8
5.97
869
418
73
8.7
7.3
869
839.4
96.5
2.7
0.31
26.9
3.1
0
501
67
140
120
869
631.6
72.7
44.5
5.1
192.9
22.2
RECTIFICATION:
Barometric Press., mm.
End Point, °C.
Gas and Losses, grams
% Gas and Losses
Residue, grams
% Residue
Gasoline Product, grams
% Gasoline on Gas Oil
% Gasoline on Product
% Gasoline on Product / Gas
% Ultimate Yield
% Conversion on Charge
633.8
210.0
36.8
4.2
666.9
76.8
107.2
12.3
13.2
13.1
65.0
19.1
637.9
210.9
8.1
0.9
792
91.2
39.3
4.53
4.68
4. 67
57.0
7.94
629.1
210.0
25.5
2.9
400.7
46.2
205.4
23.6
32.5
30.4
46.5
50.8
29
TABIE III
Catalytic Cracking of Gas Oil with an On-Stream Cycle of
30 Minutes and Activated Catalyst
Run No.
Catalyst, cc.
15
900
CRACKING:
Liq.. Sp. Vel., hr-1
Temp., 0C.
Gas Rate cc. gas/gram charge
Total Gas, liters
Charge, grams
Product, grams
% Liquid Product
Gas, grams
% Gas
Carbon and Losses, grams
% Carbon and Losses
406
7.04
3.9
376
268.9
71.5
1.44
0.38
105.7
27.1
RECTIFICATION:
Barometric Press., mm
End Point, 0C.
Gas and Losses, grams
% Gas and Losses
Residue, grams
% Residue
Gasoline Product, grams
% Gasoline on Gas Oil
# Gasoline on Product
% Gasoline on Product / Gas
$ Ultimate Yield
% Conversion on Charge
637.1
210.1
6.5
1.73
233.3
62.0
29.2
7.77
10.85
10.84
21.4
36.3
I
9
900
13
900
11
900 .
455
31.8
29.5
745
634.2
85.0
10.9
1.5
99.9
13.4
I
473
40.8
21.5
395
328.9
83.3
8.0
2.0
58.1
14.7
502
65
41.3
378
279.2
73.9
15.3
4.0
83.5
22.1
512
156.2
390.7
2184
1467.4
67.2
144.8
6.6
571.8
26.2
641.4
210.5
33.1
4.45
413.5
55.4
187.6
25.2
29.6
29.2
62.8
40.1
634
210
14.5
3.6
200.4
50.8
114.0
28.8
34.7
33.8
63.3
49.1
628.8
210.0
19.2
5.1
163
43.2
97
25.6
34.8
32.9
49.5
56.8
641.5
210.5
52.1
2.2
904.4
41.4
511.9
23.4
34.9
31.7
41.7
58.6
I
I
8
1000
I
30
TABLE IV
Catalytic Cracking of Gas Oil with an On-Stream Cycle of
30 Minutes and Unactivated Catalyst
Run No.
Catalyst, cc.
20
900
19
900
18
900
17
900
CRACKING:
Liq.. Sp. VeI., hr I
Temp. 0C.
Gas Rate, cc. gas/gram charge
Total Gas, liters
Charge, grams
Product, grams
% Liquid Product
Gas, grams
% Gas
Carbon and Losses, grams
aJo Carbon and Losses
I
404
3.44
2.15
375
343.8
91.5
0.8
0.2
30.4
8.1
I
452
29.4
18.65
419
372.1
88.8
6.9
1.6
40.0
9.6
I
478
66.9
28.2
366
298.6
81.6
10.4
2.8
57.0
15.6
I
497
57.6
33.9
407
308
75.8
12.6
3.1
85.9
21.1
RECTIFICATION:
Barometric Press., mm
End Point, 0C.
Gas and Losses, grams
dJo Gas and Losses
Residue, grams
% Residue
Gasoline Product, grams
% Gasoline on Gas Oil
d
Jo Gasoline on Product
dJo Gasoline on Product / gas
dJo Ultimate Yield
d
Jo Conversion on Charge
639.2
210.2
2.3
0.61
333.5
89.4
8.0
2.13
2.33
2.32
20.4
10.6
641.4
210.5
3.3
0.7
326.1
77.8
42.7
10.2
11.5
11.3
47.7
22.2
641.8
210.6
3.3
0.9
224.7
61.5
70.2
19.2
23.5
22.7
51.4
38.5
641.8
210.6
3.6
0.9
248.5
61.2
56.2
13.8
18.2
14.3
36.4
38.7
31
TABLE V
Sulfur Content and Octane Ratings
Run Temp. 0C.
400
Sulfur Content, %
Motor Octane, 0 ml
I ml
Research Octane, 0 ml
I ml
Gravity, A.P.I.
0.663
450
475
0.384
0.457
500
0.5
77.8
80.7
79.6
—
— —
—
91. 6
— —
55.5
93.8
—
58.3
58.0
82.5
83.3
96.5
97.7
52.0
89
106
123
157
189
220
251
278
304
331
366
390
427
96.5
1.0
83
83
102
128
154
182
215
249
281
311
342
363
403
94.0
1.0
85
85
HO
141
168
192
216
242
268
301
345
374
417
94.0
1.0
84
93
112
140
168
200
233
266
296
323
357
384
423
95.9
1.0
—
92.0
ASTM DISTILLATION, F at 760 am
First Drop
5% evaporated
10%
20%
30%
40%
50%
60%
70%
80%
90%
95%
End Point
Recovery, %
Residue, %
32
2k
BE R L
SADDLES
Si
\
E /
S'
CATALYST
^2
FEED
CJ
V
A
‘T H E R M O W E L L S
-BERL
SADDLES
DRY I CE
CONDENSER
WATER _
CONDENSER
TO B L O W
DOWN
BELLOWS
PUMP
CAS
RECEI VER
Figure I
Biagram of Reaction System
METER
O-ALUM lNA
ACTIVATED
NA/ I T H
A NH Y D R OU S
H YD ROCE N
FLUORIDE
Z
O
A - A L U M I NA
UNACT IVATED
L-
LU
>~
502°C
Q
LU LU
Z
O
u>
LO
J ^ i a 0C
I19 7 3C
Z CO
4 5 2 °C y
LU <
CC
_ ^ " 4 55° (
O
-
512 °C
O
Zj CC
o
X
CO
< U
U _l
t- O
U
A l Ic
4 0 6 °C
LU
CL
4 0 4 °C
A------------ L
20
PER C E N T
JO
ULTIM ATE
40
50
YIELD
Figure 2
Effect of Temperature on Gasoline Yield
(Per Cent Gasoline on Gas Oil Charged)
70
0 —A L U M I N A A C T I V A T E D
F L U O R IDE
A -A LU MINA
WITH
A Nl-i Y DROUS
HYDROCEhj
UNACTIVATED
I- 4 0
U
3
512 °C
Q
5 0 2 °C
4 7 3°C
O
CK
'
)
4 5 5 ° C _/
CL
Q
30
D
Cf
_]
z
O
w 20
A 4 78 °C
Z
_J
O
(Tl
<
O
I- 10
4 5 2 0CzfZ
406 ‘
Z
W
U
oc
U
CL
4 0 4 °C
l
"
PER C E N T
ULTIMATE
YIELD
Figure 3
Effect of Temperature on Gasoline Yield
(Per Cent Gasoline on Liquid Product)
u>
—
PER CENT CASO l I NE YI ELD ON TOTAL PRODUCT
O-ALUM INA ACTIVATED
F L U O R IDE
W I T H A N HY D R OU S H Y D ROC E N
A - A L U M I NA U N A C T I V A T E D
PERCENT U LTIM A TE YIELD
Figure 4
Effect of Temperature on Gasoline Yield
(Per Cent Gasoline on Product Plus Gas)
...
O- A L U M I N A
FLUORIDE
ACTIVATED
W ITH
A- A L U M I N A
UNACTIVATED
ANHYDROUS
HYDROGEN
Z
O
O
_l
UJ
>
r
A/I 740 o L
2>0
W UJ
S g
_1 <
O X
(Z) O
<
O d
4 5 5 =C j
512 °C
CjU
X
20
z
I-0
G - a
Z (Z)
W <
U O
o
/ 1-78 °C
497 °C
Cf
452
O
O)
O
O
10
O
a
^ 0 , 0 2 °C
4 0 4 °C
X
60
PER C E N T C O N V E R S I O N ON C H A R G E
Figure 5
Effect of Temperature on Gasoline Yield and Per Cent Conversion
(Per Cent Gasoline on Gas Oil Charged)
O-ALUMINA ACTIVATED
FLUOR IDE
U
D
Q
O
Gd
A-ALU MINA
W IT H ANH Y DRO US
HY DROCE h
U N A C T I VATED
C
L
Q
4 7 3 "C o
D
5 0 2 °C
d
C
>12 °C
4 5 5°C
'
z
O
Q
_l
O
U
UJ
UJ
-o
>
r
UJ
Z
'
A, 497°C
_1
O
452
<
106 " C o
O
IZ
UJ
I
-T
O
O
o:
LU
Q-
IO
20
30
40
50
60
PER C E N T C O N V E R S I O N O N CHARGE
F ig u r e 6
Effect of Temperature on Gasoline Yield and Per Cent Conversion
(Per Cent Gasoline on Liquid Product)
PRODUCT
0 —A L U M I N A A C T I V A T E D
FLUORIDE
A NH Y DROU S
HYDRO GEN
UNAC TIVATED
TOTAL
A -A LU M IN A
WITH
4 7 3 °C
------ - 5 0 2 eC
512 °C
YIELD ON
4 5 5°C
F78°C
CU
PER C E N T GASOLI NE
CD
•
I
452
4 0 6 °C
497 °C
0
4 0 4 °C
I
0
IO
20
30
40
PER C E N T C O N V E R S I O N
50
60
ON C HAR GE
Figure 7
Effect of Temperature on Gasoline Yield and Per Cent Conversion
(Per Cent Gasoline on Product Plus Gas)
70
IO
0 -
A -
Q
A L U M I N A A C T I VATED W ITH ANH YDROUS H Y D R O GE N
FLUORIDE
A L U M IN A UNACTIVATED
W
O 8
a.
<
x
U
-J
O 6
(/)
<
'
O
Z
O
u>
vO
if) 4
<
O
HZ
A
U
U 2
CK
Ul
CL
380
400
420
R E A C T I ON
4 40
4 60
480
TEMPERATURE
°C
F ig u r e 8
Gas P r o d u c tio n as a F u n c tio n o f T e m p e ra tu re
5 oo
520
OF G A S O LIN E
MOTOR
CONTENT
PER C E N T
SULFUR
RATING
SULFUR CONTENT
R E SE A RCH O C T A N E
OCTANE RATING
4 80
4 40
REACTION
TEMPERATURE
500
°C
Figure 9
Octane Numbers and Sulfur Content as a Function of Temperature
MONTANA STATE UNIVERSITY LIBRARIES
Illlllllllllllli
3 1762 10014311 2
I