Function of Sodium Ligonosulfonate
Sodium lignosulfonate is a natural polymer having a strong dispersion, having a different degree of dispersion due to the molecular weight and the type of the functional group is a surface active substance can be adsorbed on a variety of solid on the surface of the particle, the metal ion exchange effect, and also because of the presence of a variety of reactive groups on its organizational structure, and thus can produce condensation or hydrogen-bonding interactions occur with other compounds. The dispersant used in the printing and dyeing industry-NNO lignin sulfonate as the main raw material compound.
Anionic surfactants. Wood pulp with sulfur dichloride aqueous solution and sulfite reaction product, is a byproduct of the production of paper pulp, ships, 4 – hydroxy – 3 – methoxybenzaldehyde polymer. Due to the different types of wood, the difference of the sulfonation reaction, the molecular weight of lignin sulfonate ranging from 200 to 10000, chemical structure has not yet been determined. Usually said low molecular weight lignin sulfonate, is a straight-chain multi-association in solution together; polymer lignin sulfonate is a branched chain, in an aqueous medium shows polymerization dielectric behavior. The crude lignin sulfonate is used extensively for animal feed grain, refined lignin sulfonate dispersant for oil drilling mud; ore flotation agent, slime, dyes, pesticides dispersant; heavy metals, especially iron, copper and stannous ions preferably chelating ability, the chelating agent is effective.
Lignin sulfonate is a natural polymer, has a strong dispersion, due to the molecular weight and the type of functional group with varying degrees of dispersion is a surface active substance can be adsorbed in a variety of solid particle on the surface, the metal ion exchange effect, and also because of the presence of a variety of reactive groups on its organizational structure, and thus can produce condensation or hydrogen-bonding interactions occur with other compounds.
The dispersant used in the printing and dyeing industry-NNO lignin sulfonate as the main raw material compound.
Use of lignin sulfonate:
The lignin sulfonate sodium (wood) extract, bamboo pulping process modification reaction was concentrated and spray drying. The product is light yellow (brown) free flowing powder, soluble in water, chemically stable, long-term sealed storage does not decompose. The lignin Series product is a surfactant, more than one product is mainly used for the resin, rubber, dyes, pesticides, ceramics, cement, asphalt, animal feed, water treatment, water can be produced by the method of modification, processing, complex coal slurry, concrete, refractories, oil drilling, compound fertilizer, smelting, casting, adhesives. The experimental results show lignosulfonate prevent sand of the soil is very effective, you can also do the fixed desert sand agent. The product is modified lignin sulfonate, its quality standards are as follows: the content of lignin sulfonate reduction of 45-50% solids content <8% Water insoluble matter <1.5% PH value (1% solution) 7-9 with The amount of water <5% fineness of 120 mesh sieve I ≤ 4%.
The main performance: Concrete water reducer: Department of powdered low-lead gas retarding superplasticizer, belonging to the anionic surface-active substances, adsorption and dispersion of cement, concrete can improve various physical properties. Reduce water consumption by more than 13%, improve the workability of concrete and cement hydration can greatly reduce the initial heat of hydration, can compound early strength agent, retarder, antifreeze, pumping, etc., and Naphthalene superplasticizer compound made the liquid admixture basic no precipitation.
CWS additives: added to the product in the preparation of coal-water slurry process, can improve the high mill output to maintain normal pulping system, to reduce the pulp and power consumption, and make the CWS improve concentration during the gasification process , oxygen consumption, coal consumption decreased, the cold gas efficiency, and to make the CWS reduce viscosity range reaches a certain stability and fluidity.
3. refractory materials and ceramic body enhancer: in the large-sized tiles and refractory bricks manufacturing process, can make body material particles firmly bonded the Dry Strength can improve more than 20% -60%.
4. a filler and a dispersing agent of the dye industry and pesticide processing: when the dispersing agent and a filler for vat dyes and disperse dyes, dye force can be increased, a more uniform coloration, and shorten the time of the dye grinding; pesticide processing can be used as fillers, dispersing agents and suspending agents, greatly improving the suspension rate and the wetting properties of the wettable powders.
5. as a binder of powder and granular materials: for iron ore powder, lead and zinc powder, pulverized coal, coke Toner pressure on the ball; extrusion of cast iron, cast steel sand repression; mud-brick wall and floor tiles molding; mineral aggregate into a ball and provides high strength, good stability, lubrication and mold good results.
6. in the drilling for the diluted dispersant, viscosity reducer; improve the mobility of crude oil transportation and reduce energy consumption. Petroleum products, as a cleansing agent, a dispersing agent, overbased additives, anti-rust agent, an antistatic agent, emulsifying viscosity reducer, elimination wax Paraffin like.
The dispersing agent is in the molecule at the same time the opposite nature of the surfactant having both oleophilic and hydrophilic. Homogeneous dispersion of the difficult to dissolve in the liquid inorganic solids of the organic pigment particles, but also to prevent sedimentation of solid particles and agglomerate, and the formation and stability of suspension desired medicament.
The role of the dispersing agent is the use of wetting and dispersing agent to reduce the time and energy needed to complete the dispersion process, the stability of the dispersed pigment dispersion, the surface properties of the modified pigment particles, adjusting the motion of the pigment particles, embodied in the following aspects : shorten the dispersion time, improve gloss, improve tinting strength and hiding power, improved color development and color, to prevent flooding and floating, prevent flocculation, to prevent subsidence.
An Experimental Study of the papermaking black liquor lignin sulfonate
The main raw material for the paper industry plant fiber resources is an important light industry, is typical of the major water users, a total displacement after the chemical industry and metallurgy industry. The discharge of waste water pollution comes mainly from the cooking waste generated in the chemical pulping process, commonly known as “black liquor”. Per ton of pulp to be discharged black liquor approximately 10t. The black liquor is a component of the complex system, wherein 70% of the organic solids, including lignin, polysaccharides, humic acid, and cellulose degradation products; 30% of the inorganic solids, including free sodium salt and a silicon-containing compound, wherein the lignin, polysaccharides, humic acid and other substances are active substances.
Lignin is a main component of the black liquor, which is based on phenyl propane derivative structural unit is connected via the C-O bond and C-C chain made of natural polymer compound having a the super molecular characteristics and high specific surface area, comprising a large number of functional groups, such as a phenolic hydroxyl group, a methoxy group, a benzyl hydroxyl group, a carbonyl group, a carboxyl group, a vinyl group, etc. is apt to occur methylolated and sulfonated, carboxylated, alkylated various chemical reactions, etc. Lignin has the nature of the phenolic hydroxyl group, a little acidification, sulfonation, can be made of a complex mixture containing lignin sulfonate, can easily be processed or used directly as a less demanding purity coal-water slurry additives.
This study based on the the black liquor resource, explore the impact of various factors on the wood pulp black liquor by the lignosulfonates.
Experimental Materials and Methods
1.1 Materials experimental black liquor taken from the pulp plant of Jilin Paper Co., Ltd., the company used in papermaking raw materials angiosperms (hardwood), black liquor lignin guaiacyl and syringyl propane constitute. The company chemical pulp alkaline pulping black liquor composition shown in Table 1.
1.2 test equipment LD5-2A low-speed centrifuge; 250 mL pressure reactor; 85-Z thermostat magnetic stirrer; XMZ digital display instrument; node thermometer.
Process shown in Figure 1.
1. 4 conditions control the reactor temperature of 110 ° C to 130 ° C; reaction time 1h; pressure 2 × 105 Pa; pH value of the reaction system 60; Na2SO3 quality score of 21%; the crude lignin 70g / l. The experimental basis of the above conditions, the production of industrial surfactants process parameters.
2 Results and discussion
2. 1 the influence of temperature on the yield of sulfonated
Be seen from Figure 2, as the temperature rises, the the sulfonated yield increase. Temperature increases, the percentage of molecules having a sufficient evaporation kinetic energy increase, resulting in a higher evaporation rate, so that the steam pressure within the autoclave to a sharp increase in the volume of the reaction solution, which in a certain extent, so compression, increase in the concentration of reactants. Collision theory, according to the chemical reaction react to simultaneously satisfy two conditions, i.e. the minimum energy limit and the appropriate orientation. The reaction temperature was increased the reaction molecule has a larger average kinetic energy of the molecules collide more effective and frequent, which is a temperature less than 120 ° C, the reaction rate increased rapidly. Slightly elevated temperature, it is enough to make the proportion of the number of molecules having the minimum energy required to cause the reaction of the collision increases a lot, which is the main reason for the improvement of the yield of lignin sulfonate. Secondly, the reaction liquid viscosity (liquid layer refers to the unit area of the flow through the tangential force apart the required distance when the fixed liquid level units to the unit speed, N / (m2 • S)) is also an important influence factors. According to the viscosity of the liquid empirical formula [7 ~ 12]: η = AeB / T (A, B is a constant), the temperature rises to reduce the reaction liquid viscosity, the lignin molecular and hydrolysis of HSO-3 reactor movement more freedom, is conducive to a collision between them, increase the effective collision frequency. 2. The test of the second pressure with a sulfonating yield correlation N2 was injected to the reactor to increase the pressure inside the autoclave. From Figure 3 it can be seen, when P 2 0 × 105PA, the pressure is no longer the key factors that influence the reaction, the yield of the overall variation smaller.
2.3 the relationship between time and the yield of sulfonated be seen from Figure 4, with the increase in reaction time, increased yield of sodium lignin sulfonate. This is in line with the general law of chemical reaction, reaction time, the greater the chance of collision of reactant molecules contact, the higher the yield. As the reaction proceeds, the concentration of reactants is gradually reduced while increasing product concentration, and the presence of the product prevents the collision between the reactants, the reaction rate decreased. Reaction after 15h, the curve to flatten, the the sulfonated yield no significant change.
2.4 Ph value of sulfonated yield can be seen from Figure 5, as the Ph value of the reaction system increases, the increase in the yield of sodium lignin sulfonate. The Ph value increased within a certain range, the precipitated lignin particles of reduced diameter, an increased contact area means that the reactant molecules, is conducive to the sulfonation reaction is carried out. In addition, the pH value of direct influence on the acidity of the sulfonation reaction system. Since the reaction of Na2SO3 first hydrolyzed to NAhSO3, in the acidic range, Ph value is the higher, the smaller the acidity, the more favorable of Na2SO3 hydrolysis, thereby promoting the reaction, so that the sulfonation Yield improving.
2. 5 lignin concentration of sulfonated yield correlation can be seen from Figure 6, the the sodium ligninsulfonate yield substantially downward trend with the increase in the concentration of crude lignin. The crude lignin concentration of less than 52 5g / L range increases with the concentration of lignin, an increase in the dissolution of lignin, thus a slight increase in yield of sulfonated; when crude lignin concentration by mass greater than 52 5g / L, and the reaction system lignin dissolution by the solubility limit of the acidity conditions undergrowth prime mostly particle state exists, the increase in the viscosity of the reaction system is not conducive to movement of the reactant collision, and thus the yield decreases with the increase in lignin content. The best quality crude lignin concentration in the reaction under the conditions of 52 5 g / L. The 2 6 Na2SO3 Cover relationship seen from Figure 7, with a sulfonating yield increased rapidly with the increase of Na2SO3 Quality Score, the yield of sodium lignin sulfonate.
Of Na2SO3 as a sulfonating agent, the sulfonation reaction is a nucleophilic substitution reaction. The reaction process Na2SO3 first hydrolysis NAhSO3, in the to sulfonated lignin role under certain conditions. According to the basic law of the chemical reaction, the greater the concentration of reactants, the reaction is carried out more quickly and completely. Of Na2SO3 higher the concentration in the case of certain lignin content, after hydrolysis, the reaction system of HSO-3 more the hso-3 increased greatly improve its collision with lignin contact to accelerate the reaction rate. The Na2SO3 is too large will cause the ash content of the product increased, at the same time excessive amount of Na2SO3 not only increase costs, but also pollute the environment.
1. in the range of 100 ° C to 120 ° C sulfonated yield increased with the reaction temperature; yield no significant change when the temperature is higher than 120 ° C to 140 ° C increased by only 1. 6%, showing that 120 ° C is the temperature of the reaction economic.
2. When P> 2 0 × 105PA when the yield impact is minimal; generally up from the kettle into pressure (1 5 2 0) × 105Pa pressure should be from the kettle into the pressure-based.
3. Reaction 1 5h substantially reached the maximum yield; sulfonated under acidic conditions yield with Ph value increases and improve.
4. with the lignin concentration increased the sulfonated yield basic downward trend, the lignin mass concentration of the reaction system to 52. 5g / L is preferred.
5. sulfonating reagent with the increase in the proportion of the absolute dry lignin is conducive to the improvement of yield, but considering the ash and environmental impact and other factors, the ratio of 21% is appropriate.