Project Description

FLOS Additive FCC additive FCC catalyst

Applicable Scope

FLOS is a promoter for selectively enhancing FCC propylene & isobutene yields.


Both propylene and isobutene from FCCU are important raw materials for chemical industry. FLOS provides a flexible solution for light olefins boosting which could be tailored in formulations according to refinery situation. FLOS-I is specially designed mainly for enhancing propylene yield while FLOS-II mainly for isobutene yield. FLOS-III is an additive for enhancing propylene and isobutene yields.

Design Philosophy

Based on the studies of hydrocarbon reaction chemistry and catalytic material chemistry, a new concept is proposed for promoting propylene & isobutene productions: the precursor for C3 and C4 olefins are essentially C6-C8 carbenium ions. Zeolites with distinct topologies can give different product selectivity. Furthermore, the acid properties of catalytic materials were modified to improve the mono-molecular cracking of C6-C8 secondary and tertiary carbenium carbonium ions and depress the hydrogen transfer reaction. Meanwhile, isomerization of n-butene is promoted by incorporating a novel matrix material.


The main specifications of FLOS additive are shown in Table 1.

Table 1 Main Specifications of FLOS

Chemical components, m%
Al2O3 ≥25.0
Na2O ≤0.30
Physical property
LOI, m% ≤13.0
Attrition Index, %/h ≤3.0
Bulk Density, g/ml 0.65-0.85
Surface Area, m2/g ≥150
Pore Volume, ml/g ≥0.22
Particle Distribution, m%
0-40 μm ≤20
0-149 μm ≥90
800℃ /4h, m% ≥45

Commercial Reference

The industrial application was conducted on MIP-CGP unit of SINOPEC Baling Petrochemical. The promoter addition started from August 2012. Performance test conducted in December 2012. Fresh promoter make up carried out on a day-to-day base. FLOS-III content in inventory reached a level of 6% in December 2012. The results are listed in Table2.

FLOS promoter exhibits excellent performance not only in enhancing propylene & isobutene yields but also in improving propylene & isobutene selectivity. According to the results of commercial application, LPG yield increased by 2.68%, in which 1.01% for propylene and 0.54% for isobutene respectively. Meanwhile the gasoline olefin content is reduced whereas RON & MON increased slightly. LCO yield decreased while the total liquid yield maintain unchanged. FLOS shows no negative influence on fluidization status in long term operation.

Table 2 Industrial Application Results of FLOS

Catalyst Base Base + FLOS
Throughput, t/d 2472 2448
Main operation conditions
Reaction temp., ℃ 527 519
Regeneration temp., ℃ 700 692
Feed Properties
Density (20 ℃ ), g/cm3 0.8787 0.8667
Carbon residue, m% 4.02 4.12
C, m% 86.07 85.56
H, m% 12.86 13.10
S, m% 0.14 0.12
Basic N, mg/kg 593 573
Fe, mg/kg 1.6 2.6
Ni, mg/kg 6.0 5.1
V, mg/kg 0.30 0.61
Na, mg/kg 1.8 4.8
Products distribution, wt%
H2S 0.06 0.05
Dry gas 2.96 3.10
LPG 27.79 30.47
Gasoline 43.23 42.81
LCO 12.80 10.71
Slurry 2.82 2.78
Coke 9.88 9.63
Loss 0.46 0.45
Total 100.00 100.00
Conversion, % 84.38 86.51
Gasoline + LCO, wt% 56.03 53.32
Total liquid yield, wt% 83.82 83.99
Propylene yield, wt% 9.10 10.11
Isobutene yield, wt% 3.43 3.97
Gasoline properties
RON 94.2 94.6
MON 82.5 82.8
Olefin content, m% 35.6 31.1

Commercial Application

Since August of 2012, FLOS-III has been used in SINOPEC Baling Petrochemical.