Furfural data

To illustrate, predictions were first made for a ternary system of type II, using binary data only. Figure 14 compares calculated and experimental phase behavior for the system 2,2,4-trimethylpentane-furfural-cyclohexane. UNIQUAC parameters are given in Table 4. As expected for a type II system, agreement is good. 

Type C requires the most complex data analysis. To illustrate, we have reduced the data of Henty (1964) for the system furfural-benzene-cyclohexane-2,2,4-trimethylpentane. VLB data were used in conjunction with one ternary tie line for each ternary to determine optimum binary parameters for each of the two type-I ternaries cyclohexane-furfural-benzene and 2,2,4-... 

The optimum parameters for furfural-benzene are chosen in the region of the overlapping 39% confidence ellipses. The ternary tie-line data were then refit with the optimum furfural-benzene parameters final values of binary parameters were thus obtained for benzene-cyclohexane and for benzene-2,2,4-trimethyl-pentane. Table 4 gives all optimum binary parameters for this quarternary system. 

Furfural is very thermally stable in the absence of oxygen. At temperatures as high as 230°C, exposure for many hours is required to produce detectable changes in the physical properties of furfural, with the exception of color (17). However, accelerating rate calorimetric data shows that a temperature above 250°C, in a closed system, furfural will spontaneously and exothermically decompose to furan and carbon monoxide with a substantial increase in pressure. The pressure may increase to 5000 psi or more, sufficient to shatter the container (18). 

Determination of xylan is frequently made by estimation of furfural production. Data so obtained, even when appropriately corrected for furfural that arises from uronic acid, may be high if araban is present in the polysaccharide preparation. In the absence of interfering carbohydrates, furfural estimation may lead to accurate xylan values. 

Data Characterizing the Wittig—Horner Reaction between Furfural and Triethyl Phosphonoacetate in the Presence of Basic Catalysts in a Batch Reactor (294)... 

Quaker Oats, Physical Data on Furfural, Bull 203, Chicago (1947) 10) W.L. Faith,... 

Development of solvent extraction processes in the petroleum industry and theoretical aspects of solvent extraction are reviewed. Six extraction processes which have received industrial acceptance are described and performance characteristics of furfural, phenol, and Duosol processes are compared. Data are presented to demonstrate the applicability of adsorption analyses for stock evaluation and prediction of commercial extraction yields. Correlations for predicting solvent requirements and layer compositions and process design and engineering considerations are included. The desirability of further fundamental work to facilitate design calculations from physical data is suggested. 

The vapor heat cupacity of funtn has been measured experimentally. w Stull and co workers tabulated the vupor heat capacity of dioxanc and furan from 259C to 72 f Data lot furfural have been tubulated from 73 C to I227SC in the literature.11 The beat capacities shown lor THF, dioxanc. and furfural were estimated1 with a probable error of 5S. 

Guthrie and co-workers11" have measured tile liquid heal capacity of funm from - KJX to 2r C . The room lempeta-lure value have been determined for dioxanc" urn) furfural," The method of Yuan and Slid has been used to extend the useful range ol the data/ ... 

Coca, J., Diaz, R. (1980) Extraction of furfural from aqueous solutions with chlorinated hydrocarbons. J. Chem. Eng. Data 25, 80-83. 

To optimize the operating conditions for the detoxification of the hydrolysates with resins, experiments were carried out with synthetic solutions. Table 3 shows how the detoxifying efficiency of the anionic resin Dowex 1 diminished with increasing treated volume. Aliquots of the solution eluted through the column were sampled after 120,230, and 250 mL. As a whole, after the early 600 mL, the column still had a fair cleaning efficiency for acids but a reduced removal efficiency toward the furan compounds the data show that the cleaning efficiency of the column was 99% for formic acid, 87% for acetic acid, 40% for HMF, and 46% for furfural. An optimized resin/solution ratio of 0.14 g/g was thus extrapolated. The addition of a subsequent detoxification step with the cationic resin Dowex-50W left the concentrations of the acids almost unchanged whereas it further reduced those of HMF and furfural by 14 and 26%, respectively. The detoxification of the hydrolysate was performed on the basis of this optimized detoxification setup. 

The monosaccharides and acetic acid recoveries obtained on enzymatic posthydrolysis are also provided in Table 1. The concentrations of formic and levulinic acids, HMF, and furfural concentrations were also determined, but in all cases, they remained unchanged throughout the enzymatic process. The same trend was observed for the total phenolic content (data not shown). 

From the reported data (Figs. 1 and 2, Table 1) the optimum condition to obtain a pentose-rich hydrolysate from dilute-acid hydrolysis of BSG at 130°C was 15 min (CS 1.94). Such hydrolysate contains about 43.5 g/L of glucose, xylose, and arabinose (ratio of 10 67 32), together with a low content of furfural, HMF, acetic acid, formic acid, and total phenolic compounds (Table 2). This condition was chosen for subsequent production of hydrolysates for fermentation. 

For all conditions tested, D. hansenii was able to consume all furfural and HMF, regardless of the type of hydrolysate (data not shown). Acetic acid consumption ranged from 90 to 100%. Formic acid was only fully consumed for detoxified and supplemented hydrolysates. The complete consumption of acetic acid in hydrolysates has already been reported by other investigators (44,45). 

Figure 2. Experimental solubilities of furfural in supercritical CO2 and with equation of Chrastil calculated data...

SAFETY PROFILE Confirmed carcinogen. Poison by ingestion, intraperitoneal, subcutaneous, intravenous, and intramuscular routes. Moderately toxic by inhalation and skin contact. Human mutation data reported. A skin and eye irritant. Mutation data reported. The liquid is dangerous to the eyes. The vapor is irritating to mucous membranes and is a central nervous system poison. However, its low volatility reduces its toxicity effect. Ingestion of furfural has produced cirrhosis of the liver in rats. In industry there is a tendency to minimize the danger of acute effects resulting from exposure to it. This is particularly tme because of its low volatility. 

The submitters, starting with 266.3 g (2.77 mol) of furfural, obtained the product as colorless crystals, mp 57-59°C and found that, upon stirring the mother liquors at -78°C and seeding, an additional 70.3 g (total yield of 77%) of the butenolide could be obtained. The checkers noted that their product could be decolorized by charcoal treatment (twice) of a chloroform solution heated at reflux to furnish an analytically pure sample of the furanone with mp 54°C. The product displays the following spectral data H NMR (300 MHz, CDCy 5 5.24 (br s, IH), 6.23 (dd, 1.2, 5.4, IH), 6.27 (m, IH), 7.33 (dd,... 

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