What synthetic zeolite used for vonverting alcohol to gasoline?
Answers
he investigation of alternative and renewable sources of fuel is of special interest to countries lacking petroleum reserves. Some years ago, a project in the Department of Chemistry focussed on the conversion of ethanol to petrol by the use of the synthetic zeolite HZSM-5.
ZSM-5
A related process, which uses methanol as substrate (obtained by converting methane from natural gas) has been developed to industrial scale in New Zealand and has the capacity to supply about one third of their petrol requirements.
Our study was concerned with catalyst design for the conversion of ethanol with regard to the manufacture of liquid and gaseous fuels.
HZSM-5 can be considered as a derivative of silica and alumina, both very cheap reagents. It acts as a solid acid since for each Al3+ substituted for Si4+ in the structure, an H+ ion is also needed to maintain the overall neutrality of the molecule.
The 3-D lattice built up, consists of channels through which certain small molecules can pass and react inside by a process called shape selectivity. Bulky molecules can not enter the channels and reaction of smaller molecules to larger ones is hindered by the size of the channels, Figure 1.
This restriction means that only molecules with less than say 10 carbons are produced in the reactions inside the catalyst.
Our results indicate total conversion of the ethanol and the liquid fuel produced is comparable to commercial unleaded grade petrol with a good range of aromatic and aliphatic hydrocarbons, Table 2.
GC of synfuel
The hydrocarbons were identified by GC and GC/MS analysis.
A simulation of a GC/MS showing spectra and molecular graphics is available using JSpecView and Jmol.
Name the Synthetic Zeolite used for converting Alcohol to Gasoline.
=> ZSM-5
Application of Zeolites:
- Acts as water softener & selective absorbents.
- Used as "ions-exchanger" in softening of hard water.
- For cracking of Hydrocarbons & Isomerization.