UOP cyclar process

Dehydrocyclodimerization of liquefied petrol gas (propane and butane) can be performed to yield BTX-aromatics (Table2, entry 21). Modified ZSM-5 based catalysts are used, for example in the UOP cyclar process [33], and the process will become attractive for extraction of aromatics from natural gas fields containing further C3-C4 fractions. 

Application To produce petrochemical-grade benzene, toluene and xylenes (BTX) via the aromatization of propane and butanes using the BP-UOP Cyclar process. 

The catalyst of choice remains acidic Ga-HZSM-5. The BP/UOP Cyclar process [115] used this catalyst in the 1000 bpd plant at Grangemouth, Scotland, which operated for about two years and was shut down in December 1991. With butane as feed a typical product pectrum was 65% BTX, 5% hydrogen and 30% fuel gas. UOPs continuous catalyst... 

Zn/HZSM-5 catalysts known as efficient systems for ethane and propane aromatization (the UOP Cyclar Process) also showed some activity in methane aromatization [69]. At 723 K, methane can easily be activated in the presence of ethylene in the feed and converted to higher hydrocarbons (C -C ) and aromatics (Cg-C,g), through its reaction over rare metals modified Zn/HZSM-5 zeolite catalysts. The CH conversion of 37.3% was obtained and the catalysts showed a longer lifetime than usual metal supported HZSM-5 zeolite catalysts without adding any rare-earth metals. 

C and 5 kg/cm pressure (see Molecularsieves). Selectivity for toluene and xylenes peaks at 550°C but continues with increasing temperature for hensene. The Cyclar process (Fig. 6) developed joindy by BP and UOP uses a spherical, proprietary seoHte catalyst with a nonnoble metallic promoter to convert C or C paraffins to aromatics. The drawback to the process economics is the production of fuel gas, alow value by-product. BP operated a... 

A completely new approach for BTX production has emerged in recent years. It converts to paraffins into aromatics using a modified ZSM-5 zeoHte catalyst which contains gallium (19). An example of this approach, the Cyclar process, has been in commercial operation by British Petroleum at Grangemouth, Scotiand since August 1990 (20). It uses C —feed and employs UOP s CCR technology to compensate for rapid catalyst coking. 

Although olefins are intermediates in this reaction, the final product contains a very low olefin concentration. The overall reaction is endothermic due to the predominance of dehydrogenation and cracking. Methane and ethane are by-products from the cracking reaction. Table 6-1 shows the product yields obtained from the Cyclar process developed jointly by British Petroleum and UOP. ° A simplified flow scheme for the Cyclar process is shown in Figure 6-6. 

The aromatization of liquefied petroleum gases (LPG) has been investigated for more than a decade due to its economical and strategic importance for the exploitation of natural gas reserves and valorization of light hydrocarbons obtained from petroleum refining. Commercially, these reactions using gallium modified ZSM-5 zeolite catalysts are known as Cyclar process, developed jointly by UOP and BP [1]. 

MFl is typically the preferred zeolite due to its coking resistance, but other zeolites have been used, as detailed in the tables below. The mechanism of the dehydroaromatization is covered in greater detail in Chapter 15, as are representative processes such as UOP s Cyclar process [2, 91]. 

Gallium loaded ZSM-5 is the catalyst used in the Cyclar process (UOP/BP) whereby LPG (largely propane and butane) is converted to high-octane fuels and benzene/toluene/xylene (BTX) as petrochemicals. 

Then cyclization and further II-transfer reactions follow. With propane as feed a typical product spectrum over Ga-H-ZSM5 is 64% aromatics (of which 89% BTX (benzene, toluene, xylenes, ethylbenzene)), 6% hydrogen and 30% fuel gas [44J. Reaction temperatures are in the range 450-500 °C. BP and UOP jointly developed the CYCLAR process based on Ga-H-ZSM5 as the catalyst. 

Aromatization of paraffins is one of the most important conversion process for the production of the aromatics which is of great interest in both petroleum (as gasoline blender) and petrochemical industries. The conversion of lower alkanes to higher value products like benzene, toluene and xylenes over zeolite catalysts is well studied reaction [1-4]. A process for the transformation of propane and butane to aromatics has been developed and commercialized jointly by UOP and BP [5]. The technical feasibility of C3-C4 stream aromatization has been demonstrated by 1000 bbl/day Cyclar process at Grangemouth, U.K. and 200 bbl/day Z-forming pilot plant at Kawasaki Refinery of Mitsubishi Oil, Japan. Both these processes employ high silica, medium pore ZSM-5 zeolite based catalysts for aromatization. 

Figure 1.21 Process flow diagram for the conversion of light alkanes and alkenes to benzene, toluene, and xylene catalyzed by a gallium-modified zeolite (UOP-BP Cyclar process). Adapted from Ref. (303).

The successful incorporation of gaUium into ZSM-5 resulted in a cornerstone technology developed by UOP-BP, called the Cyclar process. This catalyst is used for aromatization of tight paraffins to aromatics. 

Gallosilicate Catalysts. Aromatization of Propane and Butane. Cyclar Process. The Cyclar process, which was discovered by BP and jointly developed with UOP, uses a single catalyst system to convert propane and butanes into aromatic hydrocarbons at high selectivity. The catalyst consists of a zeolite with a non-noble metal promoter. The zeolite component provides a shape-selective acid function, and the non-noble metal additive acts as a dehydrogenation catalyst. ... 

The main sources of feedstock for the production of aromatics will continue to be the pyrolysis products of naphtha cracking and coal carbonization, and the catalytic reforming of gasoline fractions. These raw materials will be complemented by catalytic processes to provide aromatics from small aliphatic building blocks. The first attempts along these lines are the Mofe//-MTG-process and the Cyclar process (UOP/BP). In principle, these processes are taking up attempts by Pierre E.M. Berthelot in 1866 to obtain bepzene by trimerization of acetylene. 

Industrial application of this reaction, the CYCLAR process (BP-UOP) converting C3 and C4 fraction of natural gas into C7 and Cg aromatics, was reported already in 1984 (102,106). The first industrial plant using this technology was started in Saudi Arabia in the late 1990s (102). Other industrial processes can also be mentioned (99) M-2 Forming (Mobil) and Aroforming (IFP-Salutec). 

As discussed in Section 2.5.1, extensive research in the field of aromatization have resulted in the development of commercial processes, the Mobil M2 forming,219 the Cyclar (UOP-BP),172 the Aroforming (IFP-Salutee),395 and the Alpha (Sanyo Petrochemical)396 processes. New reviews cover the fundamental and practical aspects of both monofunctional (acid-catalyzed) and bifunctional routes of aromatization.397-400 Further readings with respect to industrial applications may be find is symposia proceedings.401... 

Cooperation of chemical, refinery, and chemical engineering companies in new processes, whereby the partners use their specific know-how to accelerate process development, for example, Geminox (BP/Lurgi fluidized-bed oxidation and selective hydrogenation), Cyclar (BP/UOP fluidized-bed and regeneration technology). 

Table 12.2 lists the characteristics of the aromatization of C3—C4 paraffins developed at the Institute of Catalysis (IC) SB RAS and similar process developed abroad, such as Cyclar (UOP and BP) and Z-Forming (Mitsubishi Oil). In addition to providing higher yields of the target products (70—72% vs. 60—63%), the IC process has a simpler technological scheme. It is carried out in tubular reactors with a fixed catalyst bed, while the other processes are conducted in reactors with a moving catalyst bed. In 2006, the pilot plant with a production capacity of lOOOton/year [340] was launched into operation. 

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