Environmentally Friendly Process for the Production of Gasoline
University of Kansas
posted on 11/30/2010
Alkylation of Isobutane with various olefins is a major process in the petroleum industry for the production of environmentally friendly gasoline. Current commercial alkylation processes are catalyzed by either concentrated sulfuric acid or hydrofluoric acid. The sulfuric acid process produces large amounts of spent acid and acid soluble oils. Anhydrous HF is highly toxic and its leakage results in dangerous stable aerosols at the ground level. Hence, efforts continue to develop alternative processes that are relatively safe.
The invention is a new process for 1-butene+ alkylation to yield C8 alkylates.
Suggested Uses
Potential application in 1-butane+ alkylations that produce iso-octanes. In addition to 1-butene+ alkylations, the inventive concept could also be applicable to Friedel-Crafts alkylation and acylation chemistries. Other smaller scale processes that use liquid acids could also benefit from this technology.
Advantages
The process reduces mineral acid use by nearly 25-35 wt. % and the binary mixture shows better catalyst recyclability. The binary mixture shows increased stability, along with reduced vapor pressures of the acid mixture, enhancing the inherent safety of the process.
Detailed Description
The invention is a new process for 1-butene+ alkylation to yield C8 alkylates. It s shown that binary mixtures of certain acidic ionic liquids and mineral acids at certain compositions are either as good as or better than mineral acids alone in terms of 1-butene conversion, C8 alkylates selectivity and the ratio of trimethylpentane/dimethlyhexane (TMP/DMH) formed. It is believed that such mixtures provide tunable acidity and solubility (such that the feed components are soluble in the catalyst mixture while the C8 alkylate products are not) along with reduced vapor pressures of the acid mixture, enhancing inherent safety of the process. Further, the use of ILs replaces significant amounts (~25-35 wt.%) of mineral acid usage while also providing stable olefin conversion (>95%),
C8 alkylates selectivity (>70%) and trimethylpentane/dimethylhexane (TMP/DMH>7) selectivity over several usage cycles demonstrating the recyclability of the mineral acid+IL mixture (compared to the recyclability of the mineral acid alone).
Limitations
The cost of ionic liquids is currently high to compete with mineral acids. However, the costs are expected to be reasonable at the large scales of production that would be required to meet the IL demand for this technology.
Follow this innovation
[ via 
] [?]
request more info
Profile
