CS254165B1 - A method of producing stabilized Iignine nitrate - Google Patents

Abstract

Sulphite liquors or sulphite liquors with or without saccharides are treated with calcium hydroxide, sodium hydroxide or sodium carbonate at a temperature of 30 to 95 °C, pH 2 to 9.5 for a period of 0.5 to 24 h, while the resulting precipitate is separated at this stage but after decalcification and the resulting solution is adjusted to pH 6 to 8 with sodium hydroxide or acid sulphurous. The solution can be used in the construction of highways, water dams, concrete parking lots, runways for fetish sports, etc.

Description

SUMMARY OF THE INVENTION The present invention relates to a process for the production of sodium lignosulfonate as a plasticizer for the building industry.

In the production of plasticized concrete by homogenizing a mixture of gravel, cement and water, the most commonly used plasticizing additive in our country is the Plasticizer S. The preparation of plasticized concrete using this additive shows a drawback, because the additive itself in foaming. In addition, when mixing concrete components using this additive, unwanted air bubbles are introduced into the concrete and thus the total air content of the concrete is increased. This causes a deterioration in the properties of the cured concrete. The air content and quality are also increased by the use of Plasticizer S in mortar production. Another undesirable feature of the Plasticizer S is that it does not have stabilized flow properties, which makes it difficult for the consumer to apply it. A positive feature in addition to its good fluidizing capability of Plasticizer S is that its components also have retarding properties for concrete setting, which allows the production of plasticized concrete. This can be transported by pumps or trucks over longer distances without the risk of its curing during transport.

These drawbacks are overcome by the use of the present invention, which is characterized in that sulphite liquors and / or sulphite stillage with or without carbohydrate content stabilize their properties in advance by cleavage of aldehyde-bound sulfur dioxide and removal of sulfuric acid! from a reaction solution in an acidic or alkaline medium to form sulphites, sulphates and carbonates of calcium and sodium, from which sulphite, sulphate and calcium carbonate can be separated before and / or after decalcination, the decalcination being carried out using sodium carbonate or sulphate, a clear solution of sodium lignosulfonate is obtained which obtains excellent plasticizing effects by adjusting the pH of the solution and adding an antifoaming agent, but also by not changing the content of the carbohydrate component in the preparation.

The stabilization of the properties is carried out at a solution temperature of 30-95 ° C at pH = 2 to 9.5 for V2 hours to 24 hours in the acidic region, using the acidic reaction of sulphite leaches and / or sulphite stillage or in the alkaline region by calcium hydroxide and / or sodium hydroxide and / or sodium carbonate, whereby the precipitate formed by decalcination yields sodium lignosulphate, wherein the decalcination is carried out using an amount of sodium carbonate or sodium sulphate such that the solution of prepared sodium lignosulphonate contains no more than 0.5 to 2.5% calcium oxide calculated on the dry matter of the solution, which is another condition for obtaining a plasticizer with excellent flowing effects. In order to prevent the solution of the prepared sodium lignosulfonate from foaming and aerating the concrete and mortar, its reaction is adjusted to pH = 6-8 by the action of sodium hydroxide or sulfuric acid, the solution obtained is mixed at the manufacturer or consumer with a defoamer or mixture thereof such as ethylene oxide copolymers. with propylene oxide or unsaturated fatty acids, or fatty alcohols, or with bituminous acids, as well as copolymers of a nonylphenol derivative with oxymethylation of ethylene oxide, vegetable oil defoamers, organosilicic defoamers such as Ista D 2, Lukosan, Lukoil, thiolyl terpentine, oxyethylated, of ethylhexanol in an amount such that the air volume in the concrete or mortar mixture does not exceed 2% of the base.

This process provides a plasticizing additive with excellent flowing properties which does not foam, does not aerate the concrete or mortar but retardes and is therefore suitable for the production of plasticized ready-mixed concrete. Significantly improves the workability of concrete or cement mortar, allowing for shorter vibration times, saving on electrical energy, equipment and labor. Its use will make it possible to achieve 10–20% cement savings and also use crushed aggregate in the production of concrete, which is difficult to process without plasticizers.

The principle of a novel process for the production of sodium lignosulfonate as a plasticizing additive is exemplified by these examples.

Example 1

800 liters of concentrated sulphate liquor with conc. 41.8% and pH = 4.68 containing 21.8% monosaccharides stabilizes their chemical composition and physical properties at 70 ° C and a reaction time of 12 hours by expelling free sulfuric acid and part of the aldehyde-bound oxide from the solution by heating SO. The solution is then diluted with 5,800 liters of water, pumping 7,400 liters of a solution containing 1,343 kg of sodium carbonate with stirring, heated to 70 ° C and allowed to further stabilize for 5 to 10 days while further cleavage occurs. aldehyde-bound sulfur dioxide while forming sodium lignosulfonate, water-soluble sulfate and sodium sulfite, and insoluble by precipitation of calcium carbonate, calcium sulfate and calcium sulfite, which de-sediment as insoluble salts.

Decanting the solution yielded 32,800 liters of clear sodium lignosulfonate containing 0.5% calcium oxide. By the NaOH solution at conc. The reaction of the solution is adjusted to pH = 7.5 with 20%. 88.43 liters of a copolymer of ethylene oxide with a propylene oxide and a fraction of molecular weight of 1000-2000 are added to the solution obtained as a defoamer. The sodium lignosulfonate solution thus treated is a ready-to-use plasticizer used in the production of concrete or mortar. When applying 0.10 to 0.5 kg of dry matter of this additive per 100 kg of cement, the air content of the concrete or mortar increases by a maximum of 2% compared to the base, which is acceptable by the standard. The additive does not foam and since it contains retarding components such as monusaccharides and the lignosulfonan compounds are suitable for the production of transport concrete. The sodium lignosulfonate solution thus treated is a ready-to-use plasticizer used in the manufacture of concrete or mortar. After preparation for 5 months, the solution showed unchanged properties: pH - 6.8, did not foam when pumped, and a concrete mixture containing 340 g of SPC 325 cement at a water / cement ratio V / c = 0.303 and 0.3 kg of sodium bisulfite dry matter per 100 kg of cement, the concrete mixture had an air content of 1.3 ° / o. Since the solution contains retardants such as monosaccharides and the sodium lignosulfonate additive is suitable for the manufacture of ready-mixed concrete. At these ratios, the onset of solidification time was prolonged from the original 2.5 hours to 5 hours. EXAMPLE 1 a d 2 _

700 liters of sulf. extract of conc. 10% at 90 ° C is basified to pH = 9 with stirring with 223 liters of calcium hydroxide with conc. 13.8% calcium oxide. The solution is allowed to react for 4 hours to form a calcium sulfite, calcium sulfate and calcium lignosulfonate solution with stabilized properties. The clear solution is separated from the sediment by decantation to give 10,000 liters of clear solution, which, after concentration in a evaporator, yields 2,100 liters of calcium lignosulphonate with conc. 40%. The solution obtained by concentration is decalcined with an amount of sodium carbonate until the calcium oxide content, even after dilution with water to a volume of 3,100 liters, falls below 2.5% calculated on the dry matter. The decalcinated solution is left to sediment at 70 ° C for 10 days, the sedimented calcium carbonate, calcium sulfate, calcium sulfite is separated by decantation. The clear sodium lignosulfonate decantate is adjusted to pH = 6.5 with sulfuric acid and vigorously mixed with an antifoam mixture consisting of 1 part of a copolymer of ethylene oxide with propylene oxide with a mole. by weight of 400 to 2400 to 1 part of a copolymer of ethylene oxide with fatty alcohols, which are used in an amount such that the air volume in the concrete mixture does not exceed 2% compared to the base, using 0.1 kg to 0.5 kg dry matter of plasticizing additive sodium lignosulfonate per 100 kg of cement. When transporting 1 m ^{3 of} concrete mix containing 340 kg of SPC 325 cement, using 1.02 kg of dry matter prepared sodium lignosulfonate, the amount of ripening water can be reduced by 13 ° / o while maintaining good workability of the mixture, 60% over the base where the plasticizer does not shave. After 5 months of storage of sodium lignosulfonate the dry matter was changed by 0.2%, the pH of the solution by 0.1 aeration of the concrete mixture was not changed. The concrete mixture contained 1.1% air. The strengths of hardened concrete using the same materials were practically the same as those of the manufacturers before storage.

Example 3

000 liters of sodium lignosulfonate prepared according to Example 1 or Example 2 is mixed with a defoamer consisting of a mixture of 1 part ethylene oxide / propylene oxide copolymer to 1 part organosilicon antifoam such as Lukosan to 1 part propylene oxide copolymer with fatty alcohols in an amount of air in a concrete mix using 0.1 kg to 0.5 kg dry matter per 100 kg of cement did not increase by more than 2% compared to the base at which the prepared plasticizer was not used. Acidification and subsequent titration of the chloramine solution did not detect the presence of aldehyde-bound sulfur dioxide in the sample. Foam test on an ROS-Millesa, in which the height of the foam formed when overflowing 200 ml of the test sample according to Examples 1 and 3 of the prepared plasticizer was measured, the foam height immediately after sample preparation was 5 m / m and 4.5 m / m after 5 months storage. measurements at 40 ° C and a sample concentration of 330 g / l. When preparing 1 m ^{3 of} concrete mix from used 340 kg of SPC 325 cement by introducing 1.02 kg of sodium lignosulphonate into the mortar, reducing the mixing water content by «15 ° / o, but overcoming the same workability of the concrete mortar and maintaining 28 days of hardened concrete save 61.2 kg of cement compared to a base where the plasticizer was not used.

Sodium lignosulphonate as a plasticizer can be used in the construction industry in the manufacture of plasticized concrete, in the construction of highways, dams, concrete parking lots, airport runways, in the production of aerated concrete and as a retarder for fast-setting cements. In organic chemistry, it can be used in the manufacture of paints and in the manufacture of synthetic tanning agents. In the geological survey it can be used as a retarder in cementation of probes and for reinforcing the soil by injection. The big advantage is that it uses waste from the pulp and paper industry for the production of plasticizer, its use reduces environmental pollution and more complex use of wood mass.

251165

Its application in the construction industry will save 10 to 20% of cement if the manufacturer maintains strength values that have hardened concrete of the same composition, but without the use of a plasticizer.

SUBJECT

Claims (1)

2 5 4 1 S 5 7 By applying it to the construction industry, 10 to 20% of the cement is saved if the product retains the strength value of the 8 hardened concrete of the same composition but without the use of a plasticizer. PRED Μ ET A method for producing stabilized sodium lignosulfonate, characterized in that the nasulfite extracts and / or the sulphite stillage with or without saccharide content is calcium hydroxide and / or sodium hydroxide and / or sodium carbonate. at a temperature of 30 to 95 ° C, pH 2 to 9.5 in the form of 0.5 to 24 h, the precipitate formed is separated at this stage and / or after decalculation and the resulting solution is adjusted to pH & with up to 8 sodium or sulfuric acid. Severografia, n. P. Plant 7, Most Price 2,40 Kcs