Category Archive : Technical Support

Ammonium Lignosulfonate Used in Dyes industry

It is known to employ lignosulfonate compounds, including sodium salts of lignosulfonates, as an additive, such as a dispersant, in textile dyestuffs and printing pigments. Such lignosulfonate compounds are generally produced as a by-product of the wood pulping industry by either the sulfite or kraft process.

Such sulfonated lignin products provide three basic functions in dyestuff compositions:

(1) They assist in reducing the dye particles to a fine size;

(2) They maintain a dispersing medium for the dyestuff; and

(3) They are used as a diluent.The advantages of employing sulfonated lignins as dispersants in dyestuff compositions are based on their unique physical properties which include good compatibility with many dye systems, outstanding dispersant characteristics at ambient and elevated temperatures, and availability. There are certain disadvantages in employing lignins, whether they are sulfite lignins or sulfonated kraft lignins, as dispersants.

Negative factors in the use of such lignins as dyestuff additives relate to problems of high inorganic salt content, i.e., electrolyte content, when lowered in pH, foaming, high pH, fiber staining, poor heat stability, and high viscosity.

These adverse properties are troublesome to dyers and many attempts have been made to overcome these and other disadvantages.Inorganic electrolyte content of lignin dispersants and dyestuff additives greatly effect their use in a specific dyestuff additive formulation. High electrolyte content of a lignin dispersant imposes unwanted side effects on hydrophobic dyestuffs. In vat dyes, high salt content of the lignin additives can cause harmful rheological effects during storage of the dyes.

The viscosity of the oxidized form in the presence of salts generally increases to a level where the dye mixture can only be removed from a storage container with considerable difficulty.

Recent use in this country of double strength dyes over powder dyes has necessitated a reduced application level of the lignin dispersants in order to accomodate the increased amount of dye, thus dictating that the dispersant be in its purest state possible.A number of technological developments have resulted in new methods and processes to modify sulfonated lignins to reduce the negative aspects of employing such materials as dye dispersants without simultaneously causing any major adverse effects upon those properties which render sulfonated lignins desirable as dyestuff dispersants.

In the paper industry, lignin is obtained as a by-product from spent pulping liquors, known as black liquor, where lignocellulosic materials, such as wood, straw, cornstalks, bagasse and the like are processed to separate the cellulosic pulp from the lignin. The lignins employed in the process of this invention may readily be obtained from the kraft wood pulping process wherein the natural lignin is present as a sodium salt. In kraft pulping, the wood is subjected to the effects of strong alkali. The lignin forms a soluble sodium salt in the alkaline region which is separated from the cellulose and dissolves in the pulping liquor. The lignin is then recovered from the black liquor by acidification.

Acidification of black liquor containing the lignin salt generally may be accomplished by the introduction of carbon dioxide which converts the phenolic hydroxide groups on the lignin molecule, which are in ionized form, into their free phenolic or acidic form. This conversion renders the lignin insoluble in the black liquor and, as a result, it precipitates out. To precipitate the alkali lignins from the black liquor as water-insoluble products, black liquor initially having a pH of around 13.0 is acidified to about a pH of 10.5 at which point the lignin begins to precipitate. The lignin precipitate can be further purified by reducing the pH level to pH 2, where the lignin is coagulated and washed with water to obtain a lignin product identified as “A” lignin.

Calcium lignosulfonate

Calcium Lignosulfonate Chemical characterization

1. Composition

Lignin is the second largest component of wood. It is a highly polymerized material that makes up the middle lamella of woody fibers and holds the fibers together.

The basic units of the polymeric structure consist of three aromatic propenyl alcohols (monolignols): coniferyl alcohol (4-(3-hydroxy-1-propenyl)- 2-methoxyphenol), p-coumaryl alcohol (4-[(E)-3-hydroxyprop-1-enyl]phenol), and sinapyl alcohol (4- hydroxy-3,5-dimethoxycinnamyl alcohol), of which coniferyl alcohol represents the principle unit in lignin.

Methoxy groups are abundant on the polymeric structure providing many reactive sites and promoting its low water solubility. In calcium lignosulfonate (40-65), however, sulfonate groups are attached to the alkane
backbone units to confer water solubility and calcium anions, introduced with the calcium sulfite during the process of manufacture, stabilize them.

The degree of sulfonation on the alkane backbone has also been
established as a criterion for the identification of the additive. An upper limit of 5.0 % for calcium content was also set.

Ultraviolet spectroscopy confirms the presence of phenyl groups in the additive and infrared spectroscopy reveals bands characteristic of sulfonate at 1210-1220 cm-1, 1037 cm-1, and 655 cm-1.

A proposed structure of the polymeric fraction of calcium lignosulfonate (40-65) is presented in Figure 5.1. Representative IR and UV spectra are presented in Figures 5.2 and 5.3, respectively.

2 Impurities (including degradation products)

Impurities in calcium lignosulfonate (40-65) include monosaccharides from wood cellulose, sulfite residues and potentially arsenic and various metallic elements. Filtration, evaporation and ultrafiltration aim at reducing the content in the final product to not more than 5 % reducing sugars and not more than 0.5 % sulfite, on the dried basis, which are the bases for the establishment of corresponding limits in the specifications monograph.

A typical analysis provided by the sponsor of a single sample of the additive
showed the presence of the following reducing sugars: mannose (2.2 %), xylose (1.1 %), galactose (0.6 %),glucose (0.4 %), arabinose (0.3 %), and rhamnose (0.1%). The specifications monograph also contains maximum limits on Loss on drying (8.0 %), Total ash (14.0%), arsenic (1 mg/kg), and lead (2 mg/kg).

Potassium lignosulfonate

Sodium Lignosulphonate Used as Reinforcing Agent

Sodium Lignosulphonate ( Ceramic Body Reinforcing Agent) is one kind of modified nature lignin product. In the field of reinforcing agent for ceramic paste, the sodium lignosulphonate series products can be adopted as the main compound materials. These Sodium Lignosulphonate (HMP Ceramic Body Reinforcing Agent) attribution value is superior to other equivalent material and the economic efficiency is notable.

In the field of reinforcing agent for ceramic paste,it can enhance the strength of ceramic paste and improve the capability of molding. There will be water reducing and shortening the period for drying when mixing in the ceramic paste. It is the superior substitute goods for Carboxymethyl Cellulose .

Application of sodium lignosulphonate

Application of sodium lignosulphonate

Concrete industry:

At the concrete manufacture and dry construction,it reduces the conception of components  up to10-15% remixing of the concrete mass reduces and its solidity rises,the speed of hardeing slow down.Usage of lignosulphonate reduces humidity of raw mud if conserving its flow behaviour,which rises the manufacture of stove and reduces specific flow volume to the buring of clinker,with the usage of intensifier on the base of lignosulphonate the production of grinding units rises and there is an opportunity to change expansive and defict chemical products.

Petroleum industry:

In this area, sodium lignosulphonate is used as a flotation agent and reagent for regulating of the basic parametres of mud flushes.They are also acomponents of gel forming systerms.Gel forming leads to redistribution of fitration flows and their better regulation.Technical lignosulphonate are used for hardening of different construction types:drill well moon pool,holes,and in mine rals industry.

Building materials production:

Sodium lignosulphonate can be used in producing plates because of its astringent,sticking and surface active propertities.Because this kind of production is very expensive ,toxic,carbamide are used,mixture of  modified lignosulphonate with loam can get combined binder.Meanwhile the toxi cation of the plates can be reduced up to 50%.And in the producing of mineral-cotton plates,the products can become more firm and water-proof.

Drilling industry:

Sodium lignosulphonate can be used as a flotation reagent in minerals industry to achieve incomplete washing of separating materials. They are used for drilling well moon pool hardening and be added in different ground based in different ground bases and carpets. Sodium lignosulphonate can emulsify bituminous materials,liquid bituminous materials or coal tars,thus constructions are strengthened.

sodium lignosulfonate

Lignosulphonate used in Asphalt industry

Crack filling composition involving quaternary ammonium salt, aliphatic amine,ammonium lignosulphonate , imidazoline, and amide.

• Water stability of an asphalt mixture can be improved by

adding 0.3% lignosulphonate fibers.

• Asphalt‐emulsifying agent containing SW sodium lignosulphonate  with

an av. mol. wt. of 200‐100,000 (sodium  lignosulfonate ,and the lignosulphonate is that broad‐leaf pine or needle‐leaf pine) has the proper HLB value, slow

demulsification speed, proper frothing ability, and strong foam stability.

• Ammonium Lignosulphonate  additive has been shown to provide a warm mix additive

that can modify the combination state of asphalt and stone material surface;

modifying the fluidity; and decrease production cost of the asphalt mixtures.