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In the last decades, increasing petroleum prices, diminishing oil resources, incessant fluctuations in the oil prices and concerns about global shortage of energy resources have boosted research on production and commercialization of biofuels, e.g., ethanol and butanol, obtained from renewable resources. Besides its application as a fuel, butanol has found numerous industrial applications for the production of plasticizers, lacquers, coatings, detergents, and brake fluids. Biobutanol, together with acetone and ethanol, can be produced in industrial scale by a process called Acetone Butanol Ethanol (ABE) fermentation in anaerobic condition using Clostridium acetobutylicum bacterium. The nature of the carbohydrate and nutrients in the fermentation can affect the ratio of solvents obtained in the ABE fermentation process. In this research, influence of various nutrients and glucose concentrations on the production of butanol by this bacterium was investigated. Results showed that presence of biotin, thiamine, para-amino-benzoic acid, and yeast extract as well as several ions including Mg, Fe, Mn, phosphate, and ammonium acetate in the culture medium is essential for the production of butanol by C. acetobutylicum. Lacks of these compounds in the medium significantly reduced the production of solvents, in spite of the growth of the bacterium .also optimum concentration of glucose was 40g/l for maximum production solvent .In this concentration, maximum solvent concentration was achieved 10.5 g/l and maximum butanol concentration was achieved 6.7g/l with yield of 26.25%.

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Aims: The purpose of this article is to study the caravanserais in this area and present architectural plan patterns for suburban caravanserais on the historical road network from Isfahan to Rey and Saveh based on the spatial composition of the room with the stable.

Methods: The data collection method of this research is based on field observations and impressions, library studies, examination of architectural documents and maps of caravanserais, and study of aerial images. The analysis method is based on interpretive, historical, and comparative approaches. The method of obtaining information is inductive reasoning. 60 caravanserais have been identified in this area. From the above statistical population, 13 caravanserais have been selected as study samples. The selection of these samples was purposeful and non-probability.

Findings: The research findings indicate that some caravanserais are very similar and were built in the same period of time and their typologies are also similar to each other, which is due to the existence of a single organization and a common architect and designer, and as a result, their architectural plans and details are similar. In the statistical population of this study, 13 types and architectural patterns of caravanserais were identified based on the study of their architectural plans.

Conclusion: There are some similarities and differences among caravanserais in the research samples. Caravansers that are on a common historical path with common cultural, social and historical characteristics often have similar architectural features, so this characteristic can be used to intervene in them.