Light Olefin Production

Furthermore, the major problem of reducing aromatics is focused around gasoline production. Catalytic reforming could decrease in capacity and severity. Catalytic cracking will have to be oriented towards light olefins production. Etherification, alkylation and oligomerization units will undergo capacity increases. 

In Europe naphtha is the preferred feedstock for the production of synthesis gas, which is used to synthesize methanol and ammonia (Chapter 4). Another important role for naphtha is its use as a feedstock for steam cracking units for light olefins production (Chapter 3). Heavy naphtha, on the other hand, is a major feedstock for catalytic reforming. The product reformate containing a high percentage of Ce-Cg aromatic hydrocarbons is used to make gasoline. Reformates are also extracted to separate the aromatics as intermediates for petrochemicals. 

DCC is a novel technology derived from the FCC process for light olefins production, particularly propylene and isobutylene. New generation catalyst DMMC-1 can help to convert heavier feedstocks with increased propylene yield. 

Dharia, D., et al. Increase Light Olefins Production. Hydrocarbon Processing, April 2004. 

The findings of Bussemeier et al. and Kolbel and Tillmetz were, however, later on confirmed by the work of Barrault and co-workersand a maximum increase in light olefin production was found for bulk chemical composition Fe/Mn ratios of 1. This group also explained the promotion effects in terms of electronic changes in the metal atoms by the surrounding manganese compounds i.e., an electronic promotion effect. On the other hand, Barrault et al. also concluded that the beneficial effect of the promoter was related to the preparation method used, and more specifically to the formation of specific precursor compounds. Other preparation routes were... 

UOP and Norsk Hydro have jointly developed and demonstrated a new MTO process utilizing a SAPO-34 containing catalyst that provides up to 80% yield of ethylene and propylene at near-complete methanol conversion. Some of the key aspects of the work have included the selection of reactor design for the MTO process and determination of the effects of process conditions on product yield. Evaluation of the suitability of the MTO light olefin product as an olefin polymerization feedstock and demonstration of the stability of the MTO-lOO catalyst have also been determined during the development of this process. 

S.B. Kogan, M.L. Kaliya, N. Froumin and M. Herskowitz, Proceedings of the DGMK-Conference, Creating Value fi om Light Olefins - Production and Conversion", 2001, Hamburg, 219. 

Economics The capital cost for the MTO process units (including light olefin recovery and purification) are about 10% lower than conventional steam crackers based on producing the same amount of light olefin product. MTO projects typically include upstream process units to convert raw materials into syngas and then to methanol as well as down-... 

Haas, T. Hofen, W. Thiele, G. Kampeis, P. DGMK Tagungsbericht 2001, 2001-4, 127—130, Proceedings of the DGMK-Conference Creating Value from Light Olefins—Production and Conversion , 2001. 

Since the mid-1990s, the ZSM-5 zeolite has also been increasingly used to maximize light olefin production in fluid catalytic cracking. 

The MOI reactor operates at a lower pressure and shorter contact time than the MOG reactor to maximize light olefin production. Operating temperature is... 

It should be noted that in addition to the catalytic carbeniiun ion pathways for light olefin production, thermal reactions involving free radicals are also a signifieant souree of ethylene and indeed predominate at higher temperatures. Table 6 gives a eomparison of the impact of such thermal reactions on the yields of ethylene and propylene at different temperatures. 

Greer, D. Houdek, M. Pittman, R. Woodcock J. Creating Value from Light Olefins-Production and Conversion, Proc. the DGMK Conference, Hamburg, Germany, 2001,31-43. 

Examples of liquid additives currently in use include bismuth and antimony based additives for passivation of nickel contaminants. A number of solid catalytic additives have been developed that are specific for certain functions. Approximately two-thirds of North American units utilize a noble metal promoter to reduce emissions of CO as well as provide beneficial yield effects. During the early to mid-1980 s, SOX removal additives came into use due to tighter environmental restrictions. A ZSM-5 based additive for octane enhancement and light olefin production was developed during the mid-1980 s and is used commercially. Additives have also been proposed as metal traps especially for vanadium passivation. These solid FCC additives have become an increasingly important tool by which refiners meet yield and environmental requirements. 

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