1. Detailed
introduction
palladium based catalyst PGH-10 for first-stage
hydrogenation of pyrolysis gasoline
PGH-10 serials catalysts for first-stage hydrogenation of
pyrolysis gasoline, composed of noble metal palladium as active component and aluminum oxide as
support with adding of various additives, were mainly used in the selective
hydrogenation of pyrolysis gasoline C6~C7,
C6~C8, C5~C9, which were the
cracking byproducts in the process of ethylene production.
In order to meet the market demand, PGH-10A, a new brand
catalyst for the first-stage hydrogenation of pyrolysis gasoline, was developed
by our company at the beginning
of this century. PGH-10A made greater improvement in water resistant,
anti-arsenic, sulfur-tolerant and hydrogenation stability, etc. It was
industrial applied successfully in the petrol devices of Yanshan
Petrochemical, Shanghai Petrochemical, Lanzhou Petrochemical.
2. Physical and chemical properties
Comparison
of PGH-10 and PGH-10A
The combination of support,active component and additive
in PGH-10A was more favorable to pyrolysis gasoline hydrogenation.PGH-10A has
not only high chemical stability, high thermal stability and low rate of carbon formation, but
also good hydrogenation,anti-water, anti-impurities, anti-high-load
performance.
3. Catalyst Use Claims
3.1 Catalyst Process Operating
Conditions
operating
pressure(MPa)
≥2.4
inlet temperature (℃) initial 30~50，end 90~110
hydrogen-oil ratio (fresh feed)
(V)
60~120
space velocity (fresh
oil) (h-1）
≤3.5
3.2 Composition of
Hydrogenation Raw Oil
3.2.1 Disposal Oil
distillate
C6~ C8、C5~C9
boiling range (℃)
50~175
diene content (gI2/100g.oil)
≤35
bromine number(gBr2/100g.oil)
≤70
arsenic
content(ppb)
≤20
gum content (mg/100ml)
≤10
inorganic sulfur content
(ppm)
≤3
water
content(ppm)
≤400
3.2.2 Hydrogen
purity（v%）
≥85
methane
Balance
CO＋CO2（ppm）
≤5
3.2..3 Hydrogenation Product
Index and Catalyst Lifetime
hydrogenation Product diene(gI2/100g.oil)
≤2.5
catalyst guarantee lifetime
24months
first run
cycle
≥12months
4. Comparative Evaluation of PGH-10A
with competitive Catalyst
1000 h Comparative evaluation test of PGH-10A and competitive catalyst were
carried in 100ml Insulation installation. The details were showed in following:
4.1 Evaluation Device
catalyst bed temperature of the evaluation device which
was imported from Xytel companies USA was controlled in three sessions. The temperature
difference of insulation bed reactor was < ±0.5 ℃ between inside and outside.
Raw materials oil, hydrogen were injected into the pre-heater and mixted. when
the temperature of the mixture reached the target temperature,operating
parameters were tracking controlled automatically by a computer. The reaction
products were isolated after condensation: oil was injected into the product
tank, exhaust gas was emptyed after measurement and the bromine number
and diene value of oil were analysized.
4.2 Conditions of technological
Evaluation
Operating pressure: 2.8MPa Inlet temperature:
35～65℃
Liquid hourly space velocity: 3.5h-1 Hydrogen-oil ratio: 80:1（Vol）
4.3 Evaluation Materials
Raw materials oil was the whole distillate oil C5~C9 pyrolysis gasoline and its properties were showed in Table follows.
Properties of Raw materials oil
4.4 Evaluation results
1000 h Comparative evaluation test of PGH-10A and competitive catalyst were
carried in 100ml Insulation installation. The result was showed in following:
Figure 1 Comparative evaluation results of the
hydrogenation product diene value with time on stream catalyzed by PGH-10A
and competitive catalyst1000 hours operation process(the diene value of raw
materials was up to 42.53gI/100g and bromine number to 104.2gBr2/100g)
indicated PGH-10A was adapted to low-grade oil and good hydrogenation
performance and its catalytic activity was considerable to competitive catalyst
in Figure 1. PGH-10A has a good hydrogenation performance and stability.