Xplore Abstract - Effect of alcohol on cellulose hydrolysis in super/subcritical alcohol-water mixtures. The focus of this work was on investigating the effects of different types of alcohol on the cellulose hydrolysis in supercritical/subcritical alcohol-water mixtures by selecting methanol, ethanol, and isopropanol as co-solvents.
The experiments were conducted in a batch reactor under the following conditions: 5% mass ratio, 0.58 min reaction time and stirring speed 600 r/min. The experimental results showed that the reducing sugar yield was very low when the alcohol mole fraction in the alcohol-water mixture was more than 0.8, however, the yield turned very high when the mole fraction was less than 0.6. Cellulose hydrolysis in subcritical and supercritical water. Abstract In this paper we propose a new method to hydrolyze cellulose rapidly in supercritical water (SCW) to recover glucose, fructose and oligomers (cellobiose, cellotriose, cellotetraose, etc.).
Supercritical fluid. Properties[edit] In general terms, supercritical fluids have properties between those of a gas and a liquid.
In Table 1, the critical properties are shown for some components, which are commonly used as supercritical fluids. Table 2 shows density, diffusivity and viscosity for typical liquids, gases and supercritical fluids. In addition, there is no surface tension in a supercritical fluid, as there is no liquid/gas phase boundary. By changing the pressure and temperature of the fluid, the properties can be "tuned" to be more liquid- or more gas-like.
All supercritical fluids are completely miscible with each other so for a mixture a single phase can be guaranteed if the critical point of the mixture is exceeded. Tc(mix) = (mole fraction A) x TcA + (mole fraction B) x TcB. For greater accuracy, the critical point can be calculated using equations of state, such as the Peng Robinson, or group contribution methods. Phase diagram[edit] Figure 1. Figure 2. Dima Bolmatov, V. Applications[edit] Patent US1443881 - Fermentation of cellulose - Google Patents. Patented Jan. 31), 1923. ' rnnmnn'rarron or cELLuLosE.
No Drawing. duction of acetic acid as the main fattyacid is possible and this fermentation has frequently been studied; however, the statements as to the conditions under which it occurs are conflicting and a practical manufacturing process cannot be deduced from them. Patent US1443881 - Fermentation of cellulose - Google Patents. The Journal of Agricultural Science - Abstract - The fermentation of cellulose by thermophilic bacteria. Research Article The fermentation of cellulose by thermophilic bacteria J.
Direct fermentation of cellulose to ethanol by Fusarium oxysporum. Fermentation Challenge: Making Ethanol from Cellulose. Ethanol From Cellulose: A General Review. Index | Search | Home | Table of Contents Badger, P.C. 2002.
Ethanol from cellulose: A general review. p. 17–21. In: J. Kraft process. The kraft process (also known as kraft pulping or sulfate process)[1] is a process for conversion of wood into wood pulp consisting of almost pure cellulose fibers.
It entails treatment of wood chips with a mixture of sodium hydroxide and sodium sulfide, known as white liquor, that breaks the bonds that link lignin to the cellulose. History[edit] Organosolv. In industrial paper-making processes, organosolv is a pulping technique that uses an organic solvent to solubilise lignin and hemicellulose.
It has been considered in the context of both pulp and paper manufacture and biorefining for subsequent conversion of cellulose to fuel ethanol. The process was invented by Theodore Kleinert[1] as an environmentally benign alternative to kraft pulping. Organosolv has several advantages when compared to other popular methods such as kraft or sulfite pulping. In particular, the ability to obtain relatively high quality lignin adds value to a process stream otherwise considered as waste. Suburban grass clippings, landfill or ethanol? Well, it might be time to do some more intensive research!
David Blumes' book has info on starch conversion methods, and makes many suggestions for crops/plants adapted to desertified or extreme/marginal land and conditions, but one would really also need to look closer to home for indigenous and/or locally developed crops easily available for trialling and eventual use. Rudie. Wood chips to biofuel in hours. Until now, it has taken weeks to make biofuel from trees.
This slow pace has been a bottleneck for the industry. Researchers from the Norwegian University of Science and Technology have now shortened the process to a few hours. "The time when we use food stock to make biofuel to power a car may soon come to an end. Currently, maize and sugar cane are used to produce biofuel," says Finn Lillelund Aachmann, a biotechnology researcher at the Norwegian University of Science and Technology. Aachmann thinks that the desire for people to have environmentally friendly fuel should not be at the expense of food. Tiny Wood Chip Machine. Making Ethanol from Wood Chips. Experimental methods for converting wood chips and grass into ethanol will soon be tested at production scale. Mascoma Corporation, based in Cambridge, MA, is building demonstration facilities that will have the capacity to produce about one-half to two million gallons of ethanol a year from waste biomass.
The startup recently received $30 million in venture-capital money, which is fueling its scale-up plans. While Mascoma has not achieved its ultimate goal of using a single genetically engineered organism to convert wood chips and other cellulosic raw materials into ethanol, the company has developed genetically modified bacteria that can speed up part of the process of producing ethanol. The optimized process shows enough promise to invest in scaling up the technology, says Colin South, Mascoma’s president.
Corn grain, the current source of ethanol in the United States, requires large amounts of land and energy to produce. Cellulosic ethanol. Cellulosic ethanol is a biofuel produced from wood, grasses, or the inedible parts of plants. It is a type of biofuel produced from lignocellulose, a structural material that comprises much of the mass of plants. Lignocellulose is composed mainly of cellulose, hemicellulose and lignin. Corn stover, Panicum virgatum (switchgrass), Miscanthus grass species, wood chips and the byproducts of lawn and tree maintenance are some of the more popular cellulosic materials for ethanol production.
Bacterial cellulose hydrolysis in anaerobic... [Ann N Y Acad Sci. 2008. Hydrolysis. Hydrolysis (/haɪˈdrɒlɨsɪs/; from Greek hydro-, meaning "water", and lysis, meaning "separation") usually means the cleavage of chemical bonds by the addition of water. Where a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g. sucrose being broken down into glucose and fructose), this is termed saccharification. Generally, hydrolysis or saccharification is a step in the degradation of a substance. Types[edit] Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both substance and water molecule to split into two parts. Salts[edit] Strong acids also undergo hydrolysis. Biofuel. A biofuel is a fuel that contains energy from geologically recent carbon fixation.
These fuels are produced from living organisms. Examples of this carbon fixation occur in plants and microalgae. Ethanol fermentation. In ethanol fermentation, one glucose molecule breaks down into two pyruvates (1). The energy from this exothermic reaction is used to bind inorganic phosphates to ADP and convert NAD+ to NADH. The two pyruvates are then broken down into two acetaldehydes and give off two CO2 as a waste product (2). The two acetaldehydes are then converted to two ethanol by using the H- ions from NADH; converting NADH back into NAD+ (3). Alcoholic fermentation, also referred to as ethanol fermentation, is a biological process in which sugars such as glucose, fructose, and sucrose are converted into cellular energy and thereby produce ethanol and carbon dioxide as metabolic waste products.
Fermentation. Scientists discover a novel way to make ethanol without corn or other plants. By Mark Shwartz Courtesy Matthew Kanan Stanford's Matthew Kanan, an assistant professor of chemistry, co-authored a study on producing liquid ethanol from carbon monoxide. Stanford University scientists have found a new, highly efficient way to produce liquid ethanol from carbon monoxide gas. This promising discovery could provide an eco-friendly alternative to conventional ethanol production from corn and other crops, say the scientists. Their results are published in the April 9 advanced online edition of the journal Nature. "We have discovered the first metal catalyst that can produce appreciable amounts of ethanol from carbon monoxide at room temperature and pressure – a notoriously difficult electrochemical reaction," said Matthew Kanan, an assistant professor of chemistry at Stanford and coauthor of the Nature study.
Ethanol Feedstocks. BioFuels Atlas. Anaerobic digestion. Anaerobic digestion also occurs naturally in some soils and in lake and oceanic basin sediments, where it is usually referred to as "anaerobic activity".[2][3] This is the source of marsh gas methane as discovered by Volta in 1776.[4][5] The digestion process begins with bacterial hydrolysis of the input materials. Insoluble organic polymers, such as carbohydrates, are broken down to soluble derivatives that become available for other bacteria.
Acidogenic bacteria then convert the sugars and amino acids into carbon dioxide, hydrogen, ammonia, and organic acids. These bacteria convert these resulting organic acids into acetic acid, along with additional ammonia, hydrogen, and carbon dioxide. Finally, methanogens convert these products to methane and carbon dioxide.[6] The methanogenic archaea populations play an indispensable role in anaerobic wastewater treatments.[7] It is used as part of the process to treat biodegradable waste and sewage sludge. History[edit] Gas street lamp.