The production of butanol from Jamaica bay macro algae

Abstract

This study ascertained the technical potential of producing biofuel from a naturally occurring macroalgae. The algae examined grow in Jamaica Bay, New York City, on water containing nitrates, phosphates, and carbon dioxide that comes from the atmosphere. The process consisted of manual and mechanical harvesting, drying, grinding, and subjecting the algal matter to acid hydrolysis to extract carbohydrates to form an algal sugar solution. Fermentation of that solution to butanol was performed with butanol ultimately removed by distillation. An average of 15.2 g/L of reducing sugars was extracted in the hydrolysate showing that macroalgae (Ulva lactuca) have significant usable carbohydrates after hydrolysis. It was found necessary to remove the excess solids from the hydrolysate prior to fermentation, as the productivity fell by 75% if this was not done. With the bacterial strains (Clostridium beijerinckii and C. saccharoperbutylacetonicum) and the algal sugar solutions used, an acetone butanol ethanol (ABE) fermentation was used to make butanol. The butanol concentration in the fermentation broth reached about 4 g/L, which is close to the theoretical value for the sugar concentration obtained, and compares well (when adjusted for sugar concentration in the media) with values reported in the literature for other systems. The recovery of reducing sugars in the media during the pilot study was 0.29 g butanol/g sugar. © 2011 American Institute of Chemical Engineers Environ Prog, 2012

Continuous Fermentation of Clostridium tyrobutyricum with Partial Cell Recycle as a Long-Term Strategy for Butyric Acid Production

“…Ramey's description of a two-step fermentation process in which sugar is converted to butyric acid in step one, and butyric acid to butanol in step two, raises the theoretical yield of butanol by 67% [2,6]. However, there has been concern that in order to upgrade butyric acid to butanol, additional energy in the form of glucose is needed, and this adversely affects the selectivity of the two-step fermentation process [7,8]. Thus, a second two-step option is fermentation production of butyric acid, followed by catalytic hydrogenation to produce butanol.…”

Macroalgae-Derived Biofuel: A Review of Methods of Energy Extraction from Seaweed Biomass

“…Butanol has been explored as a transportation fuel for around 100 years, and has been suggested as a biofuel with the potential, not only to augment, but even replace ethanol as a gasoline additive due to its, low vapour pressure and higher energy density [155]. Butanol production from biomass could also be more energy-efficient than ethanol as some bacteria used in butanol production digest not only starch and sugars, but also cellulose [152].…”

A Review: Microalgae and Their Applications in CO2 Capture and Renewable Energy

“…In general, a fermentation of sugars with Clostridium sp. can produce acetone, butanol and ethanol (ABE) in the ratio of 3:6:1 acetone:butanol:ethanol, which can be called ABE fermentation (Potts et al, 2012). ABE fermentation is typically featured by anaerobic bacterial metabolisms, acidogenesis and solventogenesis.…”

“…Clostridia species absorb these acids to produce ABE. In contrast to the ABE fermentation, Ramey (2006) proposed to accomplish the fermentation in two steps to improve yield, in which sugar was converted to butyric acid in the first step by bacterium such as Clostridium tryobutyricum in acidogenesis phase, and butyric acid to butanol in the second step by solventogenesis bacterium such as Clostridium beijerinckii Ellis et al, 2012;Potts et al, 2012). However, in order to convert butyric acid to butanol, additional energy in the form of glucose is required, adversely affecting the selection of twostep fermentation methods.…”