Olefin plants process variables

Olefins plants, for the most part, all have the same basic technology, but the process flows differ with the varied feedstocks that can be used. This chapter will cover in some depth the feeds, the hardware, the reactions, and the variables that can be manipulated to change the amount and mix of products. The physical properties of ethylene and propylene, which present some unique handling problems, will be covered also. 

A manufacturing precast for producing ortho-phthalate otters derived from alkyl acid ortho-phthalatos and olefins has boon developed and demonstrated on the pilot plant scale. Process variables Include choice of reactants, stoichiometry, reaction kinetics, recycle of recovered materials and the fate of the perchloric add catalyst. Seme physical properties of the ortho-phthalate esters have been determined and severed of the esters have been evaluated as plasticizers for polyvinyl chloride. The composite data show that the acid-olefin esterification process provides commercially acceptable plasticizers for polyvinyl chloride. 

The polymerization of light olefins using copper pyrophosphate is licensed by The M. W. Kellogg Co. under patents of the Polymerization Process Corp. The process is essentially the same as the U.O.P. process but instead uses a copper pyrophosphate catalyst (18). The first plant was built in 1939 (22) and several more have been put into operation since that time. A correlation of operating variables for this process was published in 1949 (21) it shows how conversion is influenced by catalyst activity, temperature, ratio of propene plus n-butene to isobutene, and the space velocity of olefins and of total feed when operating at 900 pounds per square inch gage pressure. A catalyst life of 100 to 150 gallons of polymer per pound of catalyst is claimed (15). 

Conversion of 88 to 94 per cent of the olefins is common, and for the pyrophosphate process the conversion has been related to reactor temperature, space velocity-, and catalyst activity as indicated in Fig. 20-8. The conversion in phosphoric acid plants is a function of the same variables, but it seems that the temperature range is higher in the phosphoric acid process (350 to 450 F), and somewhat higher space velocities (gph per lb catalyst) are used. Likewise, lower temperatures (300 to 400 F) are recommended for the liquid phosphoric acid process. ... 

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