**2. Properties of iron oxide catalyst**

Several studies reported the catalytic cracking of heavy oil with iron oxide catalysts. Fumoto et al. developed the ZrO<sup>2</sup> -supporting *α*-Fe<sup>2</sup> O3 catalysts for oxidative cracking of petroleum residual oil under high steam temperature [3]. Hosseinpour et al. reported catalytic cracking of petroleum residual oil using silica-supported *α*-Fe<sup>2</sup> O3 nanoparticles under super critical water [4]. Nguye-Huy and Shin studied steam catalytic cracking of petroleum residual oil using ZrO<sup>2</sup> -impregnated macro-mesoporous red mud, which consisted of *α*-Fe<sup>2</sup> O3 and TiO<sup>2</sup> [5]. Phase diagram of ferrite showed that Fe<sup>2</sup> O3 is alloyed with Al2 O3 homogeneously [6]. Hence, Fumoto et al. modified the ZrO<sup>2</sup> -supporting *α*-Fe<sup>2</sup> O3 catalysts by addition of Al to enhance the catalyst durability [7, 8]. We described the properties of the *α*-Fe<sup>2</sup> O3 catalysts containing Zr and Al in this section.

#### **2.1. Preparation of** *α***-Fe2 O3 catalyst containing Zr and Al**

The *α*-Fe<sup>2</sup> O3 catalyst containing Zr and Al was prepared by a coprecipitation method using aqueous solution of FeCl<sup>3</sup> ·6H2 O (Special grade, Wako Pure Chemical Industries, Ltd., 146 mol/m<sup>3</sup> ), AlCl3 ·6H2 O (Special grade, Wako Pure Chemical Industries, Ltd., 19 mol/m<sup>3</sup> ), and ZrOCl<sup>2</sup> ·8H2 O (Special grade, Wako Pure Chemical Industries, Ltd., 9 mol/m<sup>3</sup> ) with aqueous ammonia [9, 10]. The catalyst was pelletized without binder, crushed, and sieved to obtain particles of 300– 850 μm after the treatment at 873 K for 1 h in a stem atmosphere. The atomic ratio of Fe, Zr, and Al in the catalyst was 1:0.06:0.13.

#### **2.2. Structure of** *α***-Fe2 O3 catalyst containing Zr and Al**

The morphology of the *α*-Fe<sup>2</sup> O3 catalyst containing Zr and Al was analyzed by scanning electron microscope (SEM, JSM-6010LA, JEOL Ltd.). **Figure 1** showed a SEM image of *α*-Fe<sup>2</sup> O3 catalyst containing Zr and Al prepared by a coprecipitation method. The catalyst was composed of randomly shaped particles.

The crystalline construction of the catalyst was analyzed by X-ray diffraction (XRD, M03XHF22, Mac Science Co. Ltd.). **Figure 2** showed the XRD patterns of the catalyst and regent iron (III) oxide (*α*-Fe<sup>2</sup> O3 , first grade, Wako Pure Chemical Industries, Ltd.) [9]. The patterns of the catalyst corresponded to that of *α*-Fe<sup>2</sup> O3 . Absence of peaks corresponding to ZrO<sup>2</sup> and Al2 O<sup>3</sup> indicates high dispersion of Al and Zr in the *α*-Fe<sup>2</sup> O3 matrix [7]. The peaks of the catalyst are broader compared to the reagent iron oxide, indicating that the domain size of the *α*-Fe<sup>2</sup> O3 lattice was small. The catalyst containing Zr and Al showed smaller domain size than the ZrO<sup>2</sup> -supporting *α*-Fe<sup>2</sup> O3 catalyst without Al, and the small domain size positively affected the catalyst durability [7, 8].

**Figure 1.** SEM image of *α*-Fe<sup>2</sup> O3 catalyst containing Zr and Al.

[1, 2]. Heavy oil was decomposed with Ni-Mo or Co-Mo catalysts to produce light hydrocarbons with less coke under high hydrogen pressure in the hydrocracking process. The hydrocracking is a useful technique to produce light hydrocarbons, which has high H/C ratio,

Steam can be an alternative hydrogen source for conversion of heavy oil to light hydrocarbons with catalysts. This technique requires the following catalyst properties: (i) a high ability to decompose heavy oil, (ii) stable activity under high steam temperature, and (iii) resistance to deposition of coke, sulfur, and metals. Iron oxide is not expensive and can be a candidate the

This chapter describes an iron oxide-based catalyst for decomposition of heavy oil to produce light hydrocarbons. Properties of the catalyst and catalyst activity to decompose residual oil

Several studies reported the catalytic cracking of heavy oil with iron oxide catalysts. Fumoto

residual oil under high steam temperature [3]. Hosseinpour et al. reported catalytic cracking

water [4]. Nguye-Huy and Shin studied steam catalytic cracking of petroleum residual oil

O3


catalyst containing Zr and Al was prepared by a coprecipitation method using aque-


enhance the catalyst durability [7, 8]. We described the properties of the *α*-Fe<sup>2</sup>

 **catalyst containing Zr and Al**

O (Special grade, Wako Pure Chemical Industries, Ltd., 19 mol/m<sup>3</sup>

 **catalyst containing Zr and Al**

10]. The catalyst was pelletized without binder, crushed, and sieved to obtain particles of 300– 850 μm after the treatment at 873 K for 1 h in a stem atmosphere. The atomic ratio of Fe, Zr, and

tron microscope (SEM, JSM-6010LA, JEOL Ltd.). **Figure 1** showed a SEM image of *α*-Fe<sup>2</sup>

catalyst containing Zr and Al prepared by a coprecipitation method. The catalyst was com-

O3

is alloyed with Al2

O (Special grade, Wako Pure Chemical Industries, Ltd., 146 mol/m<sup>3</sup>

catalyst containing Zr and Al was analyzed by scanning elec-

O3

catalysts for oxidative cracking of petroleum

O3

nanoparticles under super critical

catalysts by addition of Al to

O3

homogeneously [6].

O3

), and ZrOCl<sup>2</sup>

) with aqueous ammonia [9,

and TiO<sup>2</sup>

catalysts

),

O3

·8H2 O

O3

although hydrogen is expensive.

178 Iron Ores and Iron Oxide Materials

catalyst to decompose heavy oil in a steam atmosphere.

and desulfurization in a steam atmosphere are discussed.

of petroleum residual oil using silica-supported *α*-Fe<sup>2</sup>

[5]. Phase diagram of ferrite showed that Fe<sup>2</sup>

**O3**

(Special grade, Wako Pure Chemical Industries, Ltd., 9 mol/m<sup>3</sup>

O3

·6H2

**O3**

Hence, Fumoto et al. modified the ZrO<sup>2</sup>

containing Zr and Al in this section.

Al in the catalyst was 1:0.06:0.13.

The morphology of the *α*-Fe<sup>2</sup>

posed of randomly shaped particles.


**2. Properties of iron oxide catalyst**

et al. developed the ZrO<sup>2</sup>

**2.1. Preparation of** *α***-Fe2**

O3

ous solution of FeCl<sup>3</sup>

**2.2. Structure of** *α***-Fe2**

using ZrO<sup>2</sup>

The *α*-Fe<sup>2</sup>

AlCl3 ·6H2

**Figure 2.** XRD patterns of *α*-Fe<sup>2</sup> O3 catalyst containing Zr and Al and regent *α*-Fe<sup>2</sup> O3 (reproduced from elsewhere [9]).

#### **3. Activity of** *α***-Fe2 O3 catalyst containing Zr and Al for decomposition of heavy oil**

almost inactive to toluene. Total flow rate of mixture of steam and nitrogen was adjusted to

(STP)/min. After 2 h of operation, the pump of AR solution was stopped, and the reactor was cooled. The gas products were separated through an ice trap and analyzed by gas chromatography (GC-12A and GC-14A, Shimadzu Corp.) with thermal conductivity and flame ionization detectors equipped with Porapak-Q and Unibeads 3S columns, respectively. The boiling point distribution was determined by the gas chromatographic distillation. The residue deposited on the catalyst was analyzed by elemental analysis (EA1110, Finningan Mat). **Figure 3** showed the composition of AR and product yield of the AR cracking at flow rate ratio

, organic gas (C<sup>1</sup>

**Figure 4** showed the XRD patterns of the used catalysts after the catalytic cracking of AR with

, Strem Chemicals, Inc.) were shown for comparison. The patterns of both used catalysts

O4

species generated from steam were incorporated into the iron oxide lattice and reacted with

with steam. Consequently, the heavy oil fractions were oxidatively cracked using oxygen spe-

When dodecylbenzene was used as a model compound of heavy oil, a small amount of oxygen containing compounds, such as phenol, acetophenone, undecanone, and hydroxybiphenyl, was produced in the catalytic cracking of dodecylbenzene [9]. Kondoh et al. reported that the

/*F*) of 0.42 g/g [9]. The high-boiling-point components, such as VGO

–C<sup>4</sup>

O3

Iron Oxide-Based Catalyst for Catalytic Cracking of Heavy Oil

http://dx.doi.org/10.5772/intechopen.72719

structure was partially maintained after the reaction

mainly appeared in the patterns of the used

<sup>18</sup>O) produced CO<sup>2</sup>

/*F* = 0.42) and composition of AR (reproduced from

), and residue. Generation of

) and iron (II, III) oxide

O3

at first [12]. Then, oxygen

reacted

181

containing

80 cm3

CO<sup>2</sup>

(Fe<sup>3</sup> O4

consisted of *α*-Fe<sup>2</sup>

cies derived from steam.

elsewhere [9]).

of steam to AR solution (*F*<sup>S</sup>

and VR, decreased, producing light oil, CO<sup>2</sup>

and Fe<sup>3</sup>

O4

O3

heavy oil fractions. Hence, the *α*-Fe<sup>2</sup>

indicated that the heavy oil fraction was oxidatively cracked.

and without steam [9]. The patterns of reagent iron (III) oxide (*α*-Fe<sup>2</sup>

with heavy oil fractions to produce light hydrocarbons and CO<sup>2</sup>

catalytic cracking of heavy oil with heavy oxygenated water (H<sup>2</sup>

**Figure 3.** Product yield of catalytic cracking of AR with steam (*F*<sup>S</sup>

. The peaks of Fe<sup>3</sup>

O3

catalyst without steam. These results indicated that part of lattice oxygen of *α*-Fe<sup>2</sup>

The *α*-Fe<sup>2</sup> O3 catalyst containing Zr and Al was used for catalytic cracking of atmospheric residual oil (AR) derived from Middle East crude [9]. **Table 1** showed the properties of AR [11]. Composition of light oil (boiling point <623 K), vacuum gas oil (VGO, boiling point 623–773 K), and vacuum residue (VR, boiling point >773 K) was determined by the gas chromatographic distillation (HP6890, Agilent Technologies) with a wide-bore capillary column according to ASTM D 2887. AR has high viscosity, low H/C ratio, and high content of highboiling-point components. This section describes the activity of the catalyst to decompose AR in a steam atmosphere.
