Lignin sulfonate

Propionic acid, C2H 02, and ammonia [7664-41-7], NH, are additives used to prevent mol ding of feed (5). Bentonite, hemiceUulose extracts, and lignin sulfonate are used to hold feed pellets together. 

Fig. 2. Flow sheet for the acid circuit processing and recovery of mica from weathered granodiorite ore. An alkaline—cationic circuit may be used by inserting a second conditioner containing lignin sulfonate, adjusting the pH to 8.0, and adding NaOH and DRL (distilled tall oil) fatty acid to the first...

Manufacturing procedures for producing dye dispersions are generally not disclosed. The principal dispersants in use include long-chain alkyl sulfates, alkaryl sulfonates, fatty amine—ethylene oxide condensates, fatty alcohol—ethylene oxide condensates, naphthalene—formaldehyde—sulfuric acid condensates, and the lignin sulfonic acids. 

Dispersants andfloeculants. These are important for the control of slimes that sometimes interfere with the selectivity and increase reagent consumption. For example, soda ash, lime sodium silicate, and lignin sulfonates are used as dispersants, and starch and polyacrylamide are used as flocculants. 

Anionic hydrophobic Polystyrene sulfonate (Na) Lignin, sulfonated 80/20 0.1 M NaNOj/CH,CN... 

During the first trials with synthetic separators around 1940 it had already been observed that some of the desired battery characteristics were affected detrimentally. The cold crank performance decreased and there was a tendency towards increased sulfation and thus shorter battery life. In extended test series, these effects could be traced back to the complete lack of wooden lignin, which had leached from the wooden veneer and interacted with the crystallization process at the negative electrode. By a dedicated addition of lignin sulfonates — so called organic expanders -— to the negative mass, not only were these disadvantages removed, but an improvement in performance was even achieved. 

Lignin sulfonates (lignosulfonates), which are also sludge conditioners. 

Synthetic examples include the poly(meth)acrylates used as flocculating agents for water purification. Biological examples are the proteins, nucleic acids, and pectins. Chemically modified biopolymers of this class are carboxymethyl cellulose and the lignin sulfonates. Polyelectrolytes with cationic and anionic substituents in the same macromolecule are called polyampholytes. 

Lignins, sulfonated or sulfomethylated reaction products with ethylene oxide, propylene oxide, butylene oxide [1571]... 

Lignins and lignin sulfonates are considered to be important tracers of man s activities. The major source of these compounds is the pulp and paper industry lignin is not a marine product, and any large accumulation of these compounds suggests a local dominance of terrestrial materials. 

Certain derivatives of the lignin sulfonic acids can be determined directly in water. The nitroso derivatives, which are easily formed in solution, can be determined by differential pulse polarography [438]. Vanillin can be formed by alkaline hydrolysis [439] or alkaline nitrobenzene oxidation [440], extracted into an organic solvent and determined by gas chromatography. 

As a general rule, fluorometric methods are considerably more sensitive than spectrophotometric methods, although standardisation is more difficult. Direct fluorometric procedures for lignin and lignin sulfonates have been described [441-443]. 

Lindberg, W., Persson, J. A., Wold, S. Anal. Chem. 55, 1983, 643-648. Partial least-squares method for spectrofluorimetric analysis of mixtures of humic acid and lignin-sulfonate. 

The influence of orthophenylene diamine and sodium lignin sulfonate on zinc electrowiiming from industrial zinc electrolyte was studied [399], A very negative effect of orthophenylene diamine on current efficiency was found. 

The present paper describes the fractionation of lignin sulfonates and kraft lignin by gel permeation chromatography (GPC) and the method developed and used for several years at the Finnish Pulp and Paper Research Institute. 

Elution of Lignin Sulfonates with Water. As can be seen from Figures 1, 2, 3, and 4, the fractionation of lignin sulfonates on elution with water through Sephadex G-50 and G-75 takes place in such a way that the logarithms of... 

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.)...

It should be noted that the relationships between molar mass and retention volume for lignin sulfonates shown in Figures 3 and 4 are strictly only valid for the samples studied in these experiments because lignin sulfonates are polyelectrolytes and thus interact with each other and with the gel matrix of the column. The shape of the calibration curve is thus affected by, among other things, the size and concentration of the sample (2). Interactions between molecular species can be eliminated by eluting with a suitable electrolyte. 

Elution of Lignin Sulfonates with Electrolyte Solution and Calibration of Columns... 

The effects caused by the electrolyte nature of lignin sulfonates are eliminated by using a 0.5M sodium chloride solution as eluent. This eluent is made 0.1M with respect to Tris-HCl and buffered to pH 8 with hydrochloric acid in order to dissolve the proteins used as calibration standards (Fig. 5). 

In the experiment described in Figure 6, four lignin sulfonate fractions with known molar masses were eluted. 

Figure 6 shows that the proteins used for calibration elute in the same way as lignin sulfonates, which justifies the use of proteins as calibration standards. A comparison between Figures 4 and 6 shows that elution with an electrolyte solution fractionates lignin sulfonates in the range 3 000-80 000 dalton, but that elution with water fractionates those in the range 20 000-100 000 dalton. 

Because of the very high molar masses of enzymically polymerized lignin sulfonates, Sephacryl S-300 is used as the gel matrix. The fractionation range is 10 000 to 1 000 000 dalton. Even in this case proteins of known molar mass can be used as calibration standards (Figs. 7 and 8). 

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