Furfural residue

For the small concentrations of interest in flashing furfural residues (5 % by weight of furfural in water corresponds to a mere 0.977 % by mole), this ratio can be well approximated by the initial slope of the vapor/liquid equilibrium curve. Referred to mass fractions, this slope is known as the amplification factor k . Its dependence on pressure is illustrated in Figure 124. As can be seen, k increases strongly with decreasing pressure. 

Among the various products that can be synthesized from biomass, methanol was selected because of its versatile applicability to the electricity, transportation, and chemical sectors. Conversion of methanol from biomass is achieved via oxygen-steam gasification followed by shift conversion and methanol synthesis. Three feedstocks were selected for conversion to methanol—wood residue, corn stover, and furfural residue. Availability of... 

Of the 5.4 MMTPY of corn produced, approximately 40% consists of residue and the remaining 60% is used as grain (4). Total annual furfural consumption in the United States is 150 million pounds. For each pound of furfural processed, approximately 10 lb of residue is produced. The furfural residue contains approximately 35% moisture (. Availability of the wood residue is estimated by assuming that only 10% of the class l-IV sites will be used for hybrid poplar plantations and that half of the wood produced will be collected as wood residue. Availability of the three biomass feedstocks is summarized in Table I. 

The base capital and annual operating costs to manufacture the final products were obtained from published date on wood residue (7) and on corn stover and furfural residue (8). The base data were updated to 1979 pricing. The product costs were calculated for three fuel grade methanol product capacities of 6,550, 13,100 and 26,200 X 10 Btu/day. The base data were adjusted using 0.7 scale factor for plant size. 

Based on raw material costs of 40/ton, 1/MM Btu, 1.62/MM Btu for corn stover, furfural residue, and wood residue, respectively. 

Thermal efficiencies for converting corn stover (8), furfural residue (8), and wood residue to methanol were estimated from the published data to be 48.0, 48.0, and 45.3% respectively. The efficiency data used for converting wood to methanol via the Purox process is also in good agreement with recently published data (12). The Purox process may not have been the best choice for the gasification (1 ). but process and economic data are available for all three feedstocks considered in this paper. 

In terms of the present methanol study, the problem seeks an optimum allocation policy for corn stover (i 1), furfural residue (i = 2), and wood residue (i = 3) to produce three commodity products of electricity (j = 1), transportation (j = 2). and chemicals (j = 3) in the most profitable way. In pure mathematical terms, we are to determine fjj which maximizes the profit function. Equation 1, when the feedstock availability and demand are constrained by Equations 2 and 3, respectively. The data base to use with Equations 1 through 4 is tabulated in Table I for Fj. Table II for Dj and Sj, Table III for ny, and Table IV for My. 

It is interesting to note that furfural residue alone was sufficient to satisfy the demand of chemical grade methanol. This is due to the fact that all the available, least expensive fuel (furfural residue), was used to manufacture the most expensive product (chemical grade methanol). The transport sector requires the second most expensive methanol fuel, and any furfural residue left over after chemical grade methanol was used for production of the transportation grade methanol. The balance of the transportation grade methanol was supplied by the wood residue, the second least expensive feedstock. All the electric utility demand was satisfied by wood residue, and no corn stover was used. 

However, a correctly specifically manufactured and configured stoker is an excellent combustor of cellulose waste such as (1) wood—shredded trees to sawdust (2) garbage—refuse-derived fuel (3) bagasse—sugarcane residne (4) industrial residue—paper, plastics, and wood (5) furfural residue (6) peanut shells and (7) shredded tires. Most of these fuels can be bnrned without auxiliary fuel with proper attention to fnel moisture, design heat release, combustion air system design, and preheated air temperature. Cogeneration and the emphasis on renewable fuels have driven increased use of these fuels. Size distribution of the fuel is important from the standpoint of efficiency, availability, and low emissions. 

Furfural Residue - 100 38 B - - - plus 40 percent H O. 3-4 percent H2SO4. traces acetic and formic acids. 

Tang Y, Bu L, He J, Jiang J (2013) L(-t)-LA production from furfural residues and com kernels with treated yeast as nutrients. Eur Food Res Technol 236 365-371. doi 10.1007/s00217-012-... 

Manufacture. Furfural is produced from aimually renewable agricultural sources such as nonfood residues of food crops and wood wastes. 

In the acid hydrolysis process (79—81), wood is treated with concentrated or dilute acid solution to produce a lignin-rich residue and a Hquor containing sugars, organic acids, furfural, and other chemicals. The process is adaptable to all species and all forms of wood waste. The Hquor can be concentrated to a molasses for animal feed (82), used as a substrate for fermentation to ethanol or yeast (82), or dehydrated to furfural and levulinic acid (83—86). Attempts have been made to obtain marketable products from the lignin residue (87) rather than using it as a fuel, but currently only carbohydrate-derived products appear practical. 

A mixture of 105.6 g. (1.1 moles) of freshly distilled furfural, 87.0 g. (1.0 mole) of 98% cyanoacetic acid (Note 1), 3.0 g. of ammonium acetate, 200 ml. of toluene, and 110 ml. of pyridine is placed in a 1-1. round-bottomed flask equipped with a Stark and Dean water trap and reflux condenser. The mixture is boiled under reflux for 2 days. The theoretical quantity of water is collected in the trap within 1 hour. Upon completion of the reflux period, the solvent is removed under reduced pressure by heating on a water bath. The residue, distilled through a 15-cm. Vigreux column at 11 mm. pressure, yields 88.6-93.3 g. (74.5-78%) of colorless liquid boiling at 95-97°, 1.5823-1.5825. 

The reaction rate increased with temperature. The hydrolysis rate of AG at temperatures lower than 70 °C was very slow. At 80 °C, only complete release of arabinose was achieved, but partially hydrolyzed galactose residue was left. The conversion of AG was 43%. A complete conversion of AG to monomers was achieved at 90 and 100 °C. After the hydrolysis at 100 °C, traces of degradation products such as furfural were observed. For this reason, the temperature for AG hydrolysis shall not exceed 100 °C. 

The injected fluids include the effluent from a sugar mill and the waste from the production of furfural, an aldehyde processed from the residues of processed sugar cane. The waste is hot (about 75°C to 93°C), acidic (pH 2.6 to 4.5), and has high concentrations of organics, nitrogen, and phosphorus.173 The waste is not classified as hazardous under 40 CFR 261, and the well is currently regulated by the State of Florida as a nonhazardous injection well. The organic carbon concentration exceeds 5000 mg/L. 

Relatively pure xylan isolated from the holocellulose of aspen (Populus) wood is said to contain 85% of xylose residues.78 One of the characteristic properties of xylan is its ease of hydrolysis. Because it hydrolyzes much more readily than cellulose, mild acid treatment may be employed to bring about preferential hydrolysis of xylan from plant material. Xylose is ordinarily prepared in the laboratory by direct sulfuric acid hydrolysis of the native xylan in ground corn cobs.74 Hydrolysis in hydrochloric acid proceeds rapidly, but decomposition to furfural also occurs to some extent.76 A commercial method for the production of D-xylose from cottonseed hulls76 and straw77 and from corn cobs17 78 has been described. 

In order to gain some information about the fundamentals of the hydrothermal carbonization process, the hydrothermal carbonization of different carbohydrates and carbohydrate products was examined [12, 13]. For instance, hydrothermal carbons synthesized from diverse biomass (glucose, xylose, maltose, sucrose, amylopectin, starch) and biomass derivatives (HMF and furfural) were treated under hydrothermal conditions at 180 °C and were analyzed with respect to their chemical and morphological structures by SEM,13 C solid-state NMR and elemental analysis. This was combined with GC-MS experiments on residual liquor solutions to analyze side products... 

The wood pyrolysis is attractive because forest and industrial wood residues can be readily converted into liqtrid products. These liqtrids, as erode bio-oil or slurry of charcoal of water or oil, have advantages in transport, storage, combustion, retrofitting and flexibility in production and marketing (Demirbas, 2007). In the first step of pyrolysis of carbohydrates dehydration occtrrs and at low temperatures dehydration predominates. Dehydration is also known as a char-forming reaction. Between 550 and 675 K volatile products, tar, and char are formed. The volatile products are CO, CO, H O, acetals, furfural, aldehydes and ketones. Levoglucosan is the principle component in tar. 

This compound is one of the more important furan derivatives, and is commercially available from pentosans (polysaccharides) which are present in rice husks, oats and corn residues (furfur is the Latin name for bran ). When treated with sulfuric acid, pentosans decompose into pentoses, which then undergo dehydration to the aldehyde (Scheme 6.31). 

Propane deasphalting is used extensively in the production of lubricating oils from residual stocks, and is almost always applied prior to selective solvent refining, where a single extraction solvent such as phenol or furfural is used. 

Absorption spectra of the phenol-sulfuric acid solutions tested for total sugars show that 5-hydroxymethylfurfural from hexoses is more common in the uppermost Silurian and Devonian samples than in the earlier deposits. Furfurals from pentose sugars evidently form the bulk of the residual carbohydrates in these samples, however. There is no definite evidence as to the marine or terrestrial origin of the hexose products in the samples. 

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