Sulfite Liquor

Sulfite [14265-45-3] Sulfite liquor Sulfite liquors Sulfite oxidase... 

Preparation from Waste Sulfite Liquors. The starting material for vanillin production can also be the lignin (qv) present in sulfite wastes from the ceUulose industry. The concentrated mother Hquors are treated with alkaH at elevated temperature and pressure in the presence of oxidants. The vanillin formed is separated from the by-products, particularly acetovanillone, 4-hydroxy-3-methoxyacetophenone, by extraction, distillation, and crystallization. 

The application of lignin as an adhesive is possible in principle. The first attempt needed very long press times due to the low reactivity (Pedersen process) [161]. This process was based on lignin polycondensation under strong acidic conditions, which led to considerable corrosion problems in the plant [161]. The particles had been sprayed with spent sulfite liquor (pH = 3-4) and pressed at 180°C. After this step, the boards were tempered in an autoclave under pressure at 170-200°C, whereby the sulfite liquor became insoluble after splitting off water and SO2. 

Shen [166-168] modified this process by spraying the particles with spent sulfite liquor containing sulfuric acid and pressing them at temperatures well above 210°C. 

An oxidative activation of the lignin also can be achieved in a biochemical way by adding enzymes (phenol oxidase laccase) to the spent sulfite liquor, whereby... 

Tankwater, Bright dip acid (phosphoric), Cyanide rinse hath, Pickle Liquor, Sodium AJuminate Liquor, N.S.S.C. Liquor, Kraft Liquor, Soda Liquor, Sulfite Liquor, Stillage, Corn Syrup, Gelatin, Salt, Soybean Oil, Steepwater, Sugar, Whey, Mercerizing Caustic, Nylon Salt, Rayon Spin Bath, and Sodium Sulfate. 

RO can recover metals, antifreeze, paint, dyes, and oils in the retentate while generating cleaned up wastewater permeate for disposal. RO is also used to reduce the volume of waste liquids (e.g., spent sulfite liquor in paper manufacturing). Wastewater treatment application removals of 95 percent TOC, > 90 percent COD, > 98 percent PAH compounds, and pesticides > 99 percent have been seen [Wilhams et al., chap. 24 in Membrane Handbook, Sirkar and Ho (eds.), Van Nostrand, 1992]. 

Howard A process for separating lignosulfonates from sulfite liquor from papermaking. The lignosulfonates are precipitated as their calcium salts. The product is used in the manufacture of vanillin. 

Pekilo [Paecilomyces] A process for making single-cell protein from waste sulfite liquor from the paper industry. The organism is Paecilomyces variotti. Used in Finland. 

Because wood sugar solutions are sterile, they permit yeast to survive under conditions that are suitable for reuse of the yeast. This procedure is similar to that used in the fermentation of sulfite liquor at the Mechan-icsville. New York, plant as early as 1913 and in Swedish and German processes since that time. Yeast reuse has also been employed for sulfite waste liquor in Canada. ... 

B. D. David, TIIC Report, Manufacture of Torula Food Yeast from Sulfite Liquor, Zellstofi-fabrik, Waldhof, May 23, 1945. 

Many plants have been constructed in Europe to utilize the sugars in sulfite liquor for the production of ethyl alcohol or food yeast. Some of these have been in commercial production 35 to 40 years, and have supplied alcohol for motor fuel and protein food for humans and animals. 

Fig. 1.42 The freeze-thaw resistance of concrete containing lignosulfonates (sulfite liquor) under saline conditions.

There is one report of the use of isopropylidene acetals, for the analysis of monosaccharides in spent sulfite liquor.229 These derivatives are not suitable for routine use, because of the time that must be taken in their preparation. 

Also a pure glycerin and so-called Gum-Sugar (a syrupy coned sugar soln which would nor crystallize) was used. The small amts of vegetable oils, or paraffin oil and the so-called concentrated waste sulfite liquor, patented in Germany after WWI, also were found suitable for stretching Gelatins... 

Production. Commercial vanillin is obtained by processing waste sulfite liquors or is synthesized from guaiacol. Preparation by oxidation of isoeugenol is of historical interest only. 

Figure 1. Fractionation of lignin sulfonates in spent sulfite liquor on Sephadex G-50. Eluent water. (Reprinted with permission from ref. 1. Copyright 1969 Wiley.)...

In order to study birch lignosulfonates, spent sulfite liquor, from which monosaccharides had been removed by ion exclusion chromatography, was fractionated on the basis of molecular size by preparative GPC (Fig. 1). 

Figure 10. Fractionation of spruce spent sulfite liquor and pine kraft black liquor.

Table I. Technical applications of spray dried spent sulfite liquors (SSL) and kraft lignin or its modifications (KL)...

Chen (29) found that the amount of sulfuric acid directly determines the hardening time in the acid condensation of spent sulfite liquors used in plywood and veneers. However, in general the adhesives based purely on acid condensed lignins have often been found to be an uneconomic and qualitatively inferior alternative to adhesives based on synthetic polymers and phenol or lignin-formaldehyde resins. 

Ammonia and ammonium persulfate can also be used as reagents (21). However, as pointed out by Nimz (48) and other authors, owing to the non-uniformity of the product, only 15% of urea-formaldehyde and 25% phenol-formaldehyde resin binder may be replaced by calcium base spent sulfite liquors. 

It has been widely known that a water-insoluble gel is obtained when spent sulfite liquors are treated with dichromate solutions. This property has been used, among other things, for increasing the tanning effect of lignosulfonates and for making oil well drilling muds. 

Milled wood lignin was mixed with the crude enzyme solution of Tram-ties versicolor extracellular phenoloxidases produced on spent sulfite liquor in a ratio of approximately 2 1. This comprised the main part of the two-component bio-adhesive. Industrial particles were bonded with 15% bioadhesive under conventional pressing conditions to have 19 mm particle boards (40 x 50 cm) of the properties described in Table IV. The bonding reaction (crosslinking) took place in aqueous solution at room temperature. If conventional pressing technology is applied, the temperature should be elevated in order to maintain water evaporation within a reasonable press time. 

Xylose is obtained from sulfite liquors, particulady from hardwoods, such as birch, by methanol extraction of concentrates or dried sulfite lyes, ultrafiltration (qv) and reverse osmosis (qv), ion exchange, ion exclusion, or combinations of these treatments (201). Hydrogenation of xylose is carried out in aqueous solution, usually at basic pH. The Raney nickel catalyst has a loading of 2% at 125°C and 3.5 MPa (515 psi) (202,203). 

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