Highway high-content smelting slag-based super sulfate cement and preparation method thereof

Abstract

The invention relates to the technical field of cement, in particular to high-dosage smelting slag-based super sulfate cement for roads and a preparation method thereof.The preparation method comprises the steps that smelting slag, alkaline residues, desulfurized gypsum, fly ash and other industrial solid waste are selected as cement base materials, the smelting slag is pretreated, then the pretreated smelting slag and auxiliaries are co-ground, and modified smelting slag is obtained; the preparation method comprises the following steps: carrying out modification treatment on lignosulfonate, firstly carrying out hydroxymethylation reaction on the lignosulfonate and formaldehyde, then grafting a chlorinated intermediate prepared from isopentenyl polyoxyethylene ether and epoxy chloropropane to obtain a lignosulfonate-based polyether monomer, then replacing isopentenyl polyoxyethylene ether in a certain proportion, and carrying out cross-linking reaction on the lignosulfonate-based polyether monomer and the modified lignosulfonate-based polyether monomer. The preparation method comprises the following steps: carrying out free radical polymerization on lignosulfonate and acrylic acid to prepare lignosulfonate branched modified polycarboxylic acid as composite lignosulfonate, and grafting a bio-based ultraviolet light absorber polyhydroxy epicatechin derivative by carboxyl-hydroxyl esterification.

Description

Technical Field

[0001] The invention relates to the technical field of cement, in particular to a high-dosage smelting slag-based supersulfate cement for highways and a preparation method thereof. Background Art

[0002] In road construction, cement is the main cementing material for roadbed, base, concrete, etc., but the production of traditional cement involves high carbon emissions and is not conducive to environmental protection.

[0003] Smelting slag is an industrial by-product of industrial iron and steel making, generally including blast furnace slag, converter slag, electric arc furnace slag, etc. It contains a large amount of heavy metal ions and has poor hydration activity. It has low strength when used directly as a cementitious material for road engineering. Under the influence of water, temperature and load, the dissolved heavy metal ions can easily affect the surrounding areas of the road. Summary of the invention

[0004] The object of the present invention is to provide a high-dosage smelting slag-based supersulfate cement for highway use and a preparation method thereof, so as to solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: A high-dosage smelting slag-based super-sulfate cement for highway use, wherein the raw material components of the cement are, by weight, 100 parts of modified smelting slag powder, 15-35 parts of composite alkali slag powder, 5-10 parts of desulfurized gypsum, 3-10 parts of fly ash, 10-25 parts of iron tailings sand, and 1-2 parts of a water reducer.

[0006] Further, the preparation of the composite alkali slag powder comprises the following steps: The alkali slag sand is centrifuged, dried, broken up and ground to obtain alkali slag sand particles, which are then mixed with the white mud and salt mud that have been filtered and dried in a mass ratio of (5-10): (65-85): (10-25), ball-milled for 30-90 minutes, and powdered to obtain composite alkali slag powder.

[0007] Furthermore, the preparation of modified smelting slag powder includes the following steps: The blast furnace slag and converter slag are ground and crushed, and sieved to obtain blast furnace slag particles and converter slag particles, and the blast furnace slag particles and converter slag particles are compounded in a mass ratio of (60-85):(15-40) to obtain smelting slag particles; the smelting slag particles, a grinding aid, and a weak acid regulator are mixed, and ball milled for 3-6 hours to obtain smelting slag powder; the smelting slag powder and the additive are mixed, ball milled at 80-140°C for 15-30 minutes, and cooled to obtain modified smelting slag powder.

[0008] Furthermore, the composition of the smelting slag powder is, by weight: 100 parts of smelting slag particles, 0.03-0.1 parts of grinding aids, and 0.5-0.9 parts of weak acid regulators.

[0009] Furthermore, the grinding aid is one of triethanolamine, ethylene glycol, glycerol, triisopropanolamine, diethanol monoisopropanolamine, and monoisopropanolamine.

[0010] Furthermore, the weak acid regulator is one of formic acid, acetic acid, oxalic acid, citric acid and tartaric acid.

[0011] Furthermore, the modified smelting slag powder has a composition of 100 parts of smelting slag powder and 0.1-0.2 parts of additives, calculated by weight.

[0012] Furthermore, the auxiliary agent is polydimethylsiloxane, isooctyl acrylate, tributyl phosphate, and dihydroxydiethylamine in a mass ratio of (10-25): (15-25): (10-30): (30-50).

[0013] Furthermore, the water reducing agent is obtained by compounding lignin sulfonate and aliphatic hydroxy sulfonate polymer in a mass ratio of 1:1.

[0014] Furthermore, the water reducing agent is a modified lignin sulfonate, and the preparation thereof comprises the following steps: (1) Mixing lignin sulfonate and deionized water, adding formaldehyde solution, adjusting the pH of the solution to 10, keeping the temperature at 99-101° C. for 170-190 minutes, cooling, concentrating, and drying to obtain hydroxymethylated lignin sulfonate; (2) heating the isopentyl polyoxyethylene ether until it is melted, adding boron trifluoride etherate and epichlorohydrin, keeping the temperature at 63-67°C for 110-130 minutes, and distilling under reduced pressure to obtain a chlorinated intermediate; mixing hydroxymethylated lignin sulfonate and deionized water, adjusting the pH to 13, adding the chlorinated intermediate, keeping the temperature at 75-85°C for 2-3 hours, adding to ethanol, concentrating, washing, and drying to obtain a lignin sulfonate-based polyether monomer; (3) Mixing lignin sulfonate-based polyether monomer, isopentyl polyoxyethylene ether, and deionized water, heating to 78-82° C., adding ammonium persulfate, stirring for 10-15 min, adding a mixed solution of acrylic acid, ascorbic acid, mercaptoethanol, and deionized water, keeping warm for 3-4 h, and adjusting the pH of the solution to 7 to obtain a composite lignin sulfonate; (4) Mix a polyhydroxy epicatechin derivative and dimethyl sulfoxide, add a mixed solution of N,N'-dicyclohexylcarbodiimide, 4-dimethylaminopyridine, dimethyl sulfoxide and composite lignin sulfonate, ultrasonically treat for 50-60 minutes, keep warm at 55-65°C for 22-24 hours, filter and wash with methanol for 3-5 times, and dry to obtain modified lignin sulfonate.

[0015] Furthermore, the auxiliary agent is prepared by compounding modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate and dihydroxydiethylamine in a mass ratio of (10-25): (15-25): (10-30): (30-50).

[0016] Further, the preparation of modified polydimethylsiloxane comprises the following steps: 1) Under nitrogen atmosphere, 1,2-epoxy-4-vinylcyclohexane, Karstedt catalyst and toluene are mixed, heated to 78-82°C, a mixture of hydrogen-terminated poly(dimethylsiloxane) and toluene is added, the temperature is raised to 98-102°C and kept for 11-12 hours, and vacuum distilled to obtain alicyclic epoxy polydimethylsiloxane; 2) Mix the polyhydroxy epicatechin derivative and dimethyl sulfoxide, raise the temperature to 65-75°C, add alicyclic epoxy polydimethylsiloxane and diethyl tetrafluoroborate, keep the temperature for 2-3 hours, add sodium carbonate, extract, and distill under reduced pressure to obtain modified polydimethylsiloxane.

[0017] Furthermore, the preparation of the polyhydroxy epicatechin derivative includes the following steps: mixing epicatechin, p-hydroxybenzoic acid and methanesulfonic acid, transferring to a 38-42°C water bath for 110-130 minutes, cooling, pouring into an ice-water mixture, vacuum filtering, washing with sodium bicarbonate solution and deionized water in sequence until the pH is neutral, vacuum filtering, freeze drying, separating and purifying on a silica gel column using petroleum ether and ethyl acetate in a volume ratio of 3:1 as eluents, and rotary evaporating to obtain a polyhydroxy epicatechin derivative.

[0018] Furthermore, a method for preparing high-dosage smelting slag-based super sulfate cement for highway use comprises the following steps: mixing modified smelting slag powder, composite alkali slag powder, desulfurized gypsum, fly ash, iron tailings sand, and water reducer, and ball milling to obtain high-dosage smelting slag-based super sulfate cement for highway use.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a high-dosage smelting slag-based super sulfate cement for highway use and a preparation method thereof. By limiting the composition and process, a high-dosage smelting slag-based super sulfate cement with the characteristics of sealing heavy metal ions, good crack resistance, excellent ultraviolet resistance and resistance to snow-melting salt erosion is prepared, thereby facilitating the low-carbon construction of road projects.

[0020] In the present invention, industrial solid wastes such as smelting slag, alkaline slag, desulfurized gypsum, fly ash, etc. are selected as cement-based materials, which plays a role in turning waste into treasure, achieving the purpose of reducing costs and increasing efficiency, and has important environmental protection, economic and social benefits. In the present invention, the smelting slag is first pretreated, and then ground with an additive to obtain modified smelting slag, and the gelling activity of the smelting slag is stimulated by salt and alkali, and the heavy metal ions in the smelting slag are sealed by ion chelation and polyester modification to avoid environmental pollution caused by the dissolution of heavy metals, which is conducive to the large-scale utilization of smelting slag solid waste and alleviates the pressure of solid waste storage.

[0021] In the present invention, lignin sulfonate and aliphatic hydroxy sulfonate polymer are compounded as a water reducer. In order to improve the compatibility of the water reducer with other admixtures and gel materials and avoid the phenomenon of water bleeding and segregation in application, the lignin sulfonate is modified to optimize its effect. First, it is used to carry out hydroxymethylation reaction with formaldehyde to prepare hydroxymethylated lignin sulfonate. The increase of hydroxyl content improves its water solubility. Then, the chlorinated intermediate prepared by isopentenyl polyoxyethylene ether and epichlorohydrin is grafted to obtain lignin sulfonate. The invention discloses a method for preparing a lignin sulfonate-based branched modified polycarboxylic acid as a composite lignin sulfonate by using a salt-based polyether monomer, and then replacing a certain proportion of isopentenyl polyoxyethylene ether, and performing free radical polymerization with acrylic acid to give the water reducer stronger dispersibility and dispersion stability, and then utilizing carboxyl-hydroxy esterification to graft a bio-based ultraviolet absorber polyhydroxy epicatechin derivative, thereby improving the dispersibility of the water reducer and the durability of the cement; wherein the polyhydroxy epicatechin derivative is prepared from the bio-based raw material epicatechin and p-hydroxybenzoic acid.

[0022] In the present invention, in the process of modifying the smelting slag, the smelting slag is modified by grinding with an auxiliary agent, and a compound of modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate and dihydroxydiethylamine is selected as an auxiliary agent; in order to improve the reaction activity of polydimethylsiloxane, the polydimethylsiloxane is modified, and 1,2-epoxy-4-vinylcyclohexane and hydrogen-terminated poly(dimethylsiloxane) are first used as raw materials to prepare alicyclic epoxy polydimethylsiloxane, and then polyhydroxy epicatechin derivatives are grafted under the catalysis of diethyl tetrafluoroborate, so as to synergistically improve the ultraviolet resistance of cement, improve the durability of sealing heavy metal ions in the smelting slag, and improve the use safety of cement. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that if the embodiments of the present invention involve directional indications such as up, down, left, right, front, and back, the directional indication is only used to explain a specific posture such as the relative position relationship between the components, the movement status, etc. If the specific posture changes, the directional indication will also change accordingly. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0025] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0026] Example 1: A method for preparing a high-dosage smelting slag-based super-sulfated cement for highway use, comprising the following steps: mixing modified smelting slag powder, composite alkali slag powder, desulfurized gypsum, fly ash, iron tailings sand, and a water reducer, and ball milling to obtain a high-dosage smelting slag-based super-sulfated cement for highway use; The raw material components of cement are: 100 parts of modified smelting slag powder, 35 parts of composite alkali slag powder, 10 parts of desulfurized gypsum, 10 parts of fly ash, 25 parts of iron tailings sand, and 1.8 parts of water reducing agent by weight. The preparation of the composite alkali slag powder comprises the following steps: The alkali slag sand is centrifuged, dried, broken up and ground to obtain alkali slag sand particles, which are then mixed with the white mud and salt mud that have been filtered and dried in a mass ratio of 10:65:25, ball-milled for 90 minutes, and powdered to obtain composite alkali slag powder; The preparation of modified smelting slag powder includes the following steps: The blast furnace slag and converter slag are ground and crushed, and sieved to obtain blast furnace slag particles and converter slag particles, and the blast furnace slag particles and converter slag particles are compounded at a mass ratio of 75:25 to obtain smelting slag particles; the smelting slag particles, a grinding aid, and a weak acid regulator are mixed, and ball milled for 5 hours to obtain smelting slag powder; the smelting slag powder and the additive are mixed, ball milled at 100° C. for 20 minutes, and cooled to obtain modified smelting slag powder; The composition of the smelting slag powder is as follows: 100 parts of smelting slag particles, 0.05 parts of grinding aids, and 0.6 parts of weak acid regulators by weight; the grinding aid is triethanolamine; the weak acid regulator is acetic acid; the composition of the modified smelting slag powder is as follows: 100 parts of smelting slag powder and 0.2 parts of the additives by weight; The auxiliary agent is prepared by mixing polydimethylsiloxane, isooctyl acrylate, tributyl phosphate and dihydroxydiethylamine in a mass ratio of 10:20:25:45; The water reducing agent is obtained by compounding lignin sulfonate and aliphatic hydroxy sulfonate polymer in a mass ratio of 1:1.

[0027] Example 2: A method for preparing a high-dosage smelting slag-based super-sulfated cement for highway use, comprising the following steps: mixing modified smelting slag powder, composite alkali slag powder, desulfurized gypsum, fly ash, iron tailings sand, and a water reducer, and ball milling to obtain a high-dosage smelting slag-based super-sulfated cement for highway use; The raw material components of cement are as follows: 100 parts of modified smelting slag powder, 15 parts of composite alkali slag powder, 5 parts of desulfurized gypsum, 3 parts of fly ash, 10 parts of iron tailings sand, and 1 part of water reducing agent by weight; The preparation of the composite alkali slag powder comprises the following steps: The alkali slag sand is centrifuged, dried, broken up and ground to obtain alkali slag sand particles, which are then mixed with the white mud and salt mud that have been filtered and dried in a mass ratio of 10:65:25, ball-milled for 30 minutes, and powdered to obtain composite alkali slag powder; The preparation of modified smelting slag powder includes the following steps: The blast furnace slag and converter slag are ground and crushed, and sieved to obtain blast furnace slag particles and converter slag particles, and the blast furnace slag particles and converter slag particles are compounded at a mass ratio of 60:40 to obtain smelting slag particles; the smelting slag particles, a grinding aid, and a weak acid regulator are mixed, and ball milled for 3 hours to obtain smelting slag powder; the smelting slag powder and the additive are mixed, ball milled at 80° C. for 30 minutes, and cooled to obtain modified smelting slag powder; The composition of the smelting slag powder is as follows: 100 parts of smelting slag particles, 0.03 parts of grinding aids, and 0.5 parts of weak acid regulators by weight; the grinding aid is triethanolamine; the weak acid regulator is acetic acid; the composition of the modified smelting slag powder is as follows: 100 parts of smelting slag powder and 0.1 parts of the additives by weight; The water reducing agent is a modified lignin sulfonate, and the preparation thereof comprises the following steps: (1) 3.2 g of lignin sulfonate and 20 mL of deionized water were mixed, 2 mL of a 37% formaldehyde solution was added, the pH of the solution was adjusted to 10, the solution was kept at 99°C for 190 min, cooled, concentrated, and dried to obtain hydroxymethylated lignin sulfonate; (2) Heat 1 mmol of isopentyl polyoxyethylene ether until it melts, add 0.02 g of boron trifluoride etherate and 1.2 mmol of epichlorohydrin, keep the temperature at 63°C for 130 min, and distill under reduced pressure to obtain a chlorinated intermediate; mix 2 g of hydroxymethylated lignin sulfonate and 50 mL of deionized water, adjust the pH to 13, add 1.2 g of the chlorinated intermediate, keep the temperature at 75°C for 3 h, add to 500 mL of ethanol, concentrate, wash, and dry to obtain a lignin sulfonate-based polyether monomer; (3) 2 g of lignin sulfonate-based polyether monomer, 8 g of isopentyl polyoxyethylene ether, and 90 mL of deionized water were mixed, heated to 78 ° C, 1 g of ammonium persulfate was added, and stirred for 10 min. A mixture of 6 g of acrylic acid and 20 mL of deionized water, and a mixture of 2 g of ascorbic acid, 3 g of mercaptoethanol, and 18 mL of deionized water were added in sequence. The mixture was kept warm for 3 h, and the pH of the solution was adjusted to 7 to obtain a composite lignin sulfonate; (4) 1.8 g of a polyhydroxy epicatechin derivative and 47 mL of dimethyl sulfoxide were mixed, and a mixed solution of 4 mL of N,N'-dicyclohexylcarbodiimide, 4 mL of 4-dimethylaminopyridine, 24 mL of dimethyl sulfoxide and 4.6 g of composite lignin sulfonate was added, and the mixture was ultrasonically treated for 50 min, kept at 55 °C for 24 h, filtered and washed with methanol for 3 times, and dried to obtain modified lignin sulfonate; The auxiliary agent is prepared by compounding modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate, and dihydroxydiethylamine in a mass ratio of 10:20:25:45. The preparation of the modified polydimethylsiloxane includes the following steps: 1) Under nitrogen atmosphere, 22g of 1,2-epoxy-4-vinylcyclohexane, 8μ Karstedt catalyst, and 13mL of toluene were mixed, heated to 78°C, 16g of a mixture of hydrogen-terminated poly(dimethylsiloxane) and 13mL of toluene were added, the temperature was raised to 98°C and kept for 12h, and the mixture was distilled under reduced pressure to obtain alicyclic epoxy polydimethylsiloxane; 2) Mix 2.5 g of polyhydroxy epicatechin derivative and 50 mL of dimethyl sulfoxide, heat to 65°C, add 4.2 g of alicyclic epoxy polydimethylsiloxane and 67 mg of diethyl tetrafluoroborate, keep warm for 2 h, add 0.1 g of sodium carbonate, extract, and distill under reduced pressure to obtain modified polydimethylsiloxane; The preparation of the polyhydroxy epicatechin derivative comprises the following steps: 2.5 mmol epicatechin, 3 mmol p-hydroxybenzoic acid and 35 mmol methanesulfonic acid are mixed, transferred to a 38° C. water bath for 130 minutes, cooled, poured into 5 mL of an ice-water mixture, vacuum filtered, washed with a sodium bicarbonate solution and deionized water in sequence until the pH value is neutral, vacuum filtered, freeze-dried, separated and purified on a silica gel column using petroleum ether and ethyl acetate in a volume ratio of 3:1 as eluents, and rotary evaporated to obtain the polyhydroxy epicatechin derivative.

[0028] Example 3: A method for preparing a high-dosage smelting slag-based super-sulfated cement for highway use, comprising the following steps: mixing modified smelting slag powder, composite alkali slag powder, desulfurized gypsum, fly ash, iron tailings sand, and a water reducer, and ball milling to obtain a high-dosage smelting slag-based super-sulfated cement for highway use; The raw material components of cement are: 100 parts of modified smelting slag powder, 25 parts of composite alkali slag powder, 6 parts of desulfurized gypsum, 8 parts of fly ash, 20 parts of iron tailings sand, and 1.8 parts of water reducing agent by mass. The preparation of the composite alkali slag powder comprises the following steps: The alkali slag sand is centrifuged, dried, broken up and ground to obtain alkali slag sand particles, which are then mixed with white mud and salt mud that have been filtered and dried in a mass ratio of 5:70:25, ball-milled for 60 minutes, and powdered to obtain composite alkali slag powder; The preparation of modified smelting slag powder includes the following steps: The blast furnace slag and converter slag are ground and crushed, and sieved to obtain blast furnace slag particles and converter slag particles, and the blast furnace slag particles and converter slag particles are compounded at a mass ratio of 75:25 to obtain smelting slag particles; the smelting slag particles, grinding aids, and weak acid regulators are mixed, and ball milled for 4 hours to obtain smelting slag powder; the smelting slag powder and the additives are mixed, ball milled at 100° C. for 20 minutes, and cooled to obtain modified smelting slag powder; The composition of the smelting slag powder is as follows: 100 parts of smelting slag particles, 0.05 parts of grinding aids, and 0.6 parts of weak acid regulators by weight; the grinding aid is triethanolamine; the weak acid regulator is acetic acid; the composition of the modified smelting slag powder is as follows: 100 parts of smelting slag powder and 0.2 parts of the additives by weight; The water reducing agent is a modified lignin sulfonate, and the preparation thereof comprises the following steps: (1) 3.2 g of lignin sulfonate and 20 mL of deionized water were mixed, 2 mL of a 37% formaldehyde solution was added, the pH of the solution was adjusted to 10, the solution was kept at 100 °C for 180 min, cooled, concentrated, and dried to obtain hydroxymethylated lignin sulfonate; (2) Heat 1 mmol of isopentyl polyoxyethylene ether until it melts, add 0.02 g of boron trifluoride etherate and 1.2 mmol of epichlorohydrin, keep the temperature at 65°C for 120 min, and distill under reduced pressure to obtain a chlorinated intermediate; mix 2 g of hydroxymethylated lignin sulfonate and 50 mL of deionized water, adjust the pH to 13, add 1.2 g of the chlorinated intermediate, keep the temperature at 80°C for 2.5 h, add to 500 mL of ethanol, concentrate, wash, and dry to obtain a lignin sulfonate-based polyether monomer; (3) 2 g of lignin sulfonate-based polyether monomer, 8 g of isopentyl polyoxyethylene ether, and 90 mL of deionized water were mixed, heated to 80 ° C, 1 g of ammonium persulfate was added, and stirred for 13 min. A mixture of 6 g of acrylic acid and 20 mL of deionized water, and a mixture of 2 g of ascorbic acid, 3 g of mercaptoethanol, and 18 mL of deionized water were added in sequence. The mixture was kept warm for 3.5 h, and the pH of the solution was adjusted to 7 to obtain a composite lignin sulfonate; (4) 1.8 g of a polyhydroxy epicatechin derivative and 47 mL of dimethyl sulfoxide were mixed, and a mixed solution of 4 mL of N,N'-dicyclohexylcarbodiimide, 4 mL of 4-dimethylaminopyridine, 24 mL of dimethyl sulfoxide and 4.6 g of a composite lignin sulfonate was added, and the mixture was ultrasonically treated for 55 min, kept at 60 °C for 23 h, filtered and washed with methanol for 4 times, and dried to obtain a modified lignin sulfonate; The auxiliary agent is prepared by compounding modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate, and dihydroxydiethylamine in a mass ratio of 10:20:25:45. The preparation of the modified polydimethylsiloxane includes the following steps: 1) Under nitrogen atmosphere, 22g of 1,2-epoxy-4-vinylcyclohexane, 8μ Karstedt catalyst, and 13mL of toluene were mixed, the temperature was raised to 80°C, 16g of a mixture of hydrogen-terminated poly(dimethylsiloxane) and 13mL of toluene were added, the temperature was raised to 100°C and kept for 11.5h, and the mixture was distilled under reduced pressure to obtain alicyclic epoxy polydimethylsiloxane; 2) Mix 2.5 g of polyhydroxy epicatechin derivative and 50 mL of dimethyl sulfoxide, heat to 70°C, add 4.2 g of alicyclic epoxy polydimethylsiloxane and 67 mg of diethyl tetrafluoroborate, keep warm for 2.5 h, add 0.1 g of sodium carbonate, extract, and distill under reduced pressure to obtain modified polydimethylsiloxane; The preparation of the polyhydroxy epicatechin derivative comprises the following steps: 2.5 mmol epicatechin, 3 mmol p-hydroxybenzoic acid and 35 mmol methanesulfonic acid are mixed, transferred to a 40°C water bath for 120 minutes, cooled, poured into 5 mL of an ice-water mixture, vacuum filtered, washed with a sodium bicarbonate solution and deionized water in sequence until the pH value is neutral, vacuum filtered, freeze-dried, separated and purified on a silica gel column using petroleum ether and ethyl acetate in a volume ratio of 3:1 as eluents, and rotary evaporated to obtain the polyhydroxy epicatechin derivative.

[0029] Example 4: A method for preparing a high-dosage smelting slag-based super-sulfated cement for highway use, comprising the following steps: mixing modified smelting slag powder, composite alkali slag powder, desulfurized gypsum, fly ash, iron tailings sand, and a water reducer, and ball milling to obtain a high-dosage smelting slag-based super-sulfated cement for highway use; The raw material components of cement are: 100 parts of modified smelting slag powder, 35 parts of composite alkali slag powder, 10 parts of desulfurized gypsum, 10 parts of fly ash, 25 parts of iron tailings sand, and 2 parts of water reducing agent by weight. The preparation of the composite alkali slag powder comprises the following steps: The alkali slag sand is centrifuged, dried, broken up and ground to obtain alkali slag sand particles, which are then mixed with the pressed and dried white mud and salt mud in a mass ratio of 8:70:22, ball milled for 90 minutes, and powdered to obtain composite alkali slag powder; The preparation of modified smelting slag powder includes the following steps: The blast furnace slag and converter slag are ground and crushed, and sieved to obtain blast furnace slag particles and converter slag particles, and the blast furnace slag particles and converter slag particles are compounded in a mass ratio of 85:15 to obtain smelting slag particles; the smelting slag particles, grinding aids, and weak acid regulators are mixed, and ball milled for 6 hours to obtain smelting slag powder; the smelting slag powder and the additives are mixed, ball milled at 140° C. for 15 minutes, and cooled to obtain modified smelting slag powder; The composition of the smelting slag powder is as follows: 100 parts of smelting slag particles, 0.1 parts of grinding aids, and 0.9 parts of weak acid regulators by weight; the grinding aid is triethanolamine; the weak acid regulator is acetic acid; the composition of the modified smelting slag powder is as follows: 100 parts of smelting slag powder and 0.15 parts of the additives by weight; The water reducing agent is a modified lignin sulfonate, and the preparation thereof comprises the following steps: (1) 3.2 g of lignin sulfonate and 20 mL of deionized water were mixed, 2 mL of a 37% formaldehyde solution was added, the pH of the solution was adjusted to 10, the solution was kept at 101°C for 170 min, cooled, concentrated, and dried to obtain hydroxymethylated lignin sulfonate; (2) Heat 1 mmol of isopentyl polyoxyethylene ether until it melts, add 0.02 g of boron trifluoride etherate and 1.2 mmol of epichlorohydrin, keep the temperature at 67°C for 110 min, and distill under reduced pressure to obtain a chlorinated intermediate; mix 2 g of hydroxymethylated lignin sulfonate and 50 mL of deionized water, adjust the pH to 13, add 1.2 g of the chlorinated intermediate, keep the temperature at 85°C for 2 h, add to 500 mL of ethanol, concentrate, wash, and dry to obtain a lignin sulfonate-based polyether monomer; (3) 2 g of lignin sulfonate-based polyether monomer, 8 g of isopentyl polyoxyethylene ether, and 90 mL of deionized water were mixed, heated to 82 °C, 1 g of ammonium persulfate was added, and stirred for 15 min. A mixture of 6 g of acrylic acid and 20 mL of deionized water, and a mixture of 2 g of ascorbic acid, 3 g of mercaptoethanol, and 18 mL of deionized water were added in sequence. The mixture was kept warm for 4 h, and the pH of the solution was adjusted to 7 to obtain a composite lignin sulfonate. (4) 1.8 g of a polyhydroxy epicatechin derivative and 47 mL of dimethyl sulfoxide were mixed, and a mixed solution of 4 mL of N,N'-dicyclohexylcarbodiimide, 4 mL of 4-dimethylaminopyridine, 24 mL of dimethyl sulfoxide and 4.6 g of a composite lignin sulfonate was added, and the mixture was ultrasonically treated for 60 min, kept at 65 °C for 22 h, filtered and washed with methanol for 5 times, and dried to obtain a modified lignin sulfonate; The auxiliary agent is prepared by compounding modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate, and dihydroxydiethylamine in a mass ratio of 10:20:25:45. The preparation of the modified polydimethylsiloxane includes the following steps: 1) Under nitrogen atmosphere, 22g of 1,2-epoxy-4-vinylcyclohexane, 8μ Karstedt catalyst, and 13mL of toluene were mixed, heated to 82°C, 16g of a mixture of hydrogen-terminated poly(dimethylsiloxane) and 13mL of toluene were added, the temperature was raised to 102°C and kept for 11h, and vacuum distillation was performed to obtain alicyclic epoxy polydimethylsiloxane; 2) Mix 2.5 g of polyhydroxy epicatechin derivative and 50 mL of dimethyl sulfoxide, heat to 75°C, add 4.2 g of alicyclic epoxy polydimethylsiloxane and 67 mg of diethyl tetrafluoroborate, keep warm for 3 h, add 0.1 g of sodium carbonate, extract, and distill under reduced pressure to obtain modified polydimethylsiloxane; The preparation of the polyhydroxy epicatechin derivative comprises the following steps: 2.5 mmol epicatechin, 3 mmol p-hydroxybenzoic acid and 35 mmol methane sulfonic acid are mixed, transferred to a 42° C. water bath and kept warm for 110 minutes, cooled, poured into 5 mL of an ice-water mixture, vacuum filtered, washed with a sodium bicarbonate solution and deionized water in sequence until the pH value is neutral, vacuum filtered, freeze-dried, separated and purified on a silica gel column using petroleum ether and ethyl acetate in a volume ratio of 3:1 as eluents, and rotary evaporated to obtain the polyhydroxy epicatechin derivative.

[0030] Comparative Example 1: Taking Example 1 as the control group, the modified smelting slag powder was replaced with smelting slag powder, and the other processes were normal.

[0031] Comparative Example 2: Taking Example 3 as the control group, sodium lignin sulfonate was used to replace the modified lignin sulfonate, and the other processes were normal.

[0032] Comparative Example 3: Taking Example 3 as the control group, the modified polydimethylsiloxane was replaced with hydrogen-terminated poly(dimethylsiloxane), and the other processes were normal.

[0033] Sources of raw materials used (for demonstration purposes only): Blast furnace slag: by mass fraction, the main chemical composition is 45% calcium oxide, 30% silicon oxide, 14% aluminum oxide, 8% magnesium oxide, and 3% iron oxide; converter slag: by mass fraction, the main chemical composition is 55% calcium oxide, 15% iron oxide, 15% silicon oxide, 10% aluminum oxide, and 5% magnesium oxide; the main components of white mud are 20% sodium chloride, 20% calcium carbonate, 20% calcium hydroxide, and 40% calcium sulfate dihydrate; salt mud: by mass fraction, the main components are 80% calcium sulfate dihydrate, 10% magnesium hydroxide, 3% sodium chloride, and 1% calcium chloride ; Alkali slag sand: by mass fraction, the main components are 40% calcium hydroxide, 58% calcium carbonate and 2% sodium chloride; desulfurized gypsum (99%): Hubei Tosoh Chemical Technology Co., Ltd.; fly ash A01085: Wuhan Jiyesheng Chemical Co., Ltd.; isopentyl polyoxyethylene ether DY-YL-330: Nantong Deyi Chemical Co., Ltd.; iron tailings sand (fineness modulus is 0.58): by mass fraction, the main components are 56.5% oxygen, 6.9% magnesium, 8.4% aluminum, 17.5% silicon, 2.6% potassium, 1.7% calcium, 4.6% iron, Titanium 0.7%; Hydrogen-terminated poly (dimethylsiloxane) 0213: Hubei Shiteng Chemical Technology Co., Ltd.; Triethanolamine T108151, lignin sulfonate (sodium lignin sulfonate) S140863, boron trifluoride etherate B431395, epichlorohydrin E108182, acrylic acid A615488, ascorbic acid A103533, mercaptoethanol M301573, dimethyl sulfoxide D103274, N,N'-dicyclohexylcarbodiimide N420184, 4-dimethylaminopyridine D109207, acrylic acid Isooctyl ester I303355, tributyl phosphate T100707, dihydroxydiethylamine D110466, 1,2-epoxy-4-vinylcyclohexane V102412, Karstedt catalyst K131673, diethyl tetrafluoroborate T498340, epicatechin E130023, p-hydroxybenzoic acid H108508, methanesulfonic acid M108501: Aladdin reagent; acetic acid, formaldehyde, ammonium persulfate, methanol, toluene, sodium carbonate, sodium bicarbonate, petroleum ether, ethyl acetate, analytical grade: Sinopharm reagent.

[0034] Performance test: The cements prepared in the embodiments and comparative examples were tested: Compressive strength: The sample size is 40mm×40mm×160mm. The sample is prepared according to 450g cement, 225g deionized water, and 1350g standard sand. It is cured for 28 days under standard curing conditions and the compressive strength test is carried out with reference to GB / T17671-2021. Anti-ultraviolet property: After 28 days of curing, the samples were irradiated with 365nm ultraviolet light for 72 hours, and the compressive strength was measured again. If the compressive strength change rate of the samples was between 0% and 1% (including 1%), it was qualified, otherwise it was unqualified. Pt 2+ Cr 3+ , Cl - Leaching: refer to HJ 557-2010 "Solid waste leaching toxicity leaching method horizontal oscillation method", GB 5085.3-2007 "Hazardous waste identification standard leaching toxicity identification" and GB / T 14848 "Groundwater quality standard" for determination. When Pt 2+ Leaching concentration (mg / L) ≤ 0.01 is qualified, Pt 2+ Leaching concentration ≤ 0.005 is excellent; Cr 3+ Leaching concentration (mg / L) ≤ 0.005 is qualified, Cr 3+ Leaching concentration ≤ 0.002 is excellent, Cl - Concentration (mg / L) ≤ 250 is qualified, Cl - The concentration ≤125 was excellent, and the results were shown in Table 1; Table 1

[0035] The present invention provides a high-dosage smelting slag-based super sulfate cement for highway use and a preparation method thereof. By limiting the composition and process, a high-dosage smelting slag-based super sulfate cement with the characteristics of sealing heavy metal ions, good crack resistance, excellent ultraviolet resistance and resistance to snow-melting salt erosion is prepared, thereby facilitating the low-carbon construction of road projects.

[0036] By comparing Example 1 with Comparative Example 1, it can be seen that the smelting slag is first pretreated and then ground with the additive to obtain the modified smelting slag, thereby improving various properties of cement.

[0037] By comparing Example 3 with Comparative Example 2, it can be seen that in order to improve the compatibility of the water reducer with other admixtures and gel materials and avoid the phenomenon of water exudation and segregation in application, the lignin sulfonate is modified to optimize its efficacy. First, it is used to react with formaldehyde for hydroxymethylation to prepare hydroxymethylated lignin sulfonate. The increase in hydroxyl content improves its water solubility. Then, it is grafted with isopentenyl polyoxyethylene ether and chlorinated intermediates prepared by epichlorohydrin to obtain lignin sulfonate-based polyether monomers. Then, a certain proportion of isopentenyl polyoxyethylene ether is replaced and free radical polymerization is carried out with acrylic acid to prepare lignin sulfonate-based branched modified polycarboxylic acid as a composite lignin sulfonate, giving the water reducer stronger dispersibility and dispersion stability. Then, carboxyl-hydroxyl esterification is used to graft a bio-based ultraviolet absorber polyhydroxy epicatechin derivative, thereby improving the dispersibility of the water reducer and the durability of the cement. The polyhydroxy epicatechin derivative is prepared from bio-based raw materials epicatechin and p-hydroxybenzoic acid.

[0038] By comparing Example 3 with Comparative Example 3, it can be seen that in the process of modifying the smelting slag in the present invention, co-grinding with an auxiliary agent is adopted for modification, and a compound of modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate, and dihydroxydiethylamine is selected as an auxiliary agent; in order to improve the reactivity of polydimethylsiloxane, polydimethylsiloxane is modified, firstly 1,2-epoxy-4-vinylcyclohexane and terminal hydrogen poly (dimethylsiloxane) are used as raw materials to prepare alicyclic epoxy polydimethylsiloxane, and then polyhydroxy epicatechin derivatives are grafted under the catalysis of diethyl tetrafluoroborate, so as to synergistically improve the UV resistance of cement, improve the durability of heavy metal ion sealing in the smelting slag, and improve the durability of cement.

[0039] The above descriptions are only embodiments of the present invention and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the present invention specification under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A high-dosage smelting slag-based supersulfate cement for highway use, characterized in that: Calculated by weight, the raw material components of cement are: 100 parts of modified smelting slag powder, 15-35 parts of composite alkali slag powder, 5-10 parts of desulfurized gypsum, 3-10 parts of fly ash, 10-25 parts of iron tailings sand, and 1-2 parts of water reducing agent.

2. The high-dosage smelting slag-based super-sulfated cement for highway use according to claim 1, characterized in that: The preparation of the composite alkali slag powder comprises the following steps: The alkali slag sand is centrifuged, dried, broken up and ground to obtain alkali slag sand particles, which are then mixed with the white mud and salt mud that have been filtered and dried in a mass ratio of (5-10): (65-85): (10-25), ball-milled for 30-90 minutes, and powdered to obtain composite alkali slag powder.

3. The high-dosage smelting slag-based super-sulfated cement for highway use according to claim 1, characterized in that: The preparation of the modified smelting slag powder comprises the following steps: The blast furnace slag and converter slag are ground and crushed, and sieved to obtain blast furnace slag particles and converter slag particles, and the blast furnace slag particles and converter slag particles are compounded in a mass ratio of (60-85):(15-40) to obtain smelting slag particles; the smelting slag particles, a grinding aid, and a weak acid regulator are mixed, and ball milled for 3-6 hours to obtain smelting slag powder; the smelting slag powder and the additive are mixed, ball milled at 80-140°C for 15-30 minutes, and cooled to obtain modified smelting slag powder.

4. The high-dosage smelting slag-based super-sulfated cement for highway use according to claim 3, characterized in that: The composition of the smelting slag powder is, by weight, 100 parts of smelting slag particles, 0.03-0.1 parts of grinding aids, and 0.5-0.9 parts of weak acid regulators; the grinding aid is one of triethanolamine, ethylene glycol, propylene glycol, triisopropanolamine, diethanol monoisopropanolamine, and monoisopropanolamine; the weak acid regulator is one of formic acid, acetic acid, oxalic acid, citric acid, and tartaric acid; the composition of the modified smelting slag powder is, by weight, 100 parts of smelting slag powder and 0.1-0.2 parts of additives.

5. The high-dosage smelting slag-based super-sulfated cement for highway use according to claim 3, characterized in that: The auxiliary agent is prepared by mixing polydimethylsiloxane, isooctyl acrylate, tributyl phosphate and dihydroxydiethylamine in a mass ratio of (10-25): (15-25): (10-30): (30-50).

6. The high-dosage smelter slag-based super-sulfated cement for highway use according to claim 1, characterized in that: The water reducing agent is obtained by compounding lignin sulfonate and aliphatic hydroxy sulfonate polymer in a mass ratio of 1:

1.

7. The high-dosage smelter slag-based super-sulfated cement for highway use according to claim 1, characterized in that: The water reducing agent is a modified lignin sulfonate, and the preparation thereof comprises the following steps: (1) Mixing lignin sulfonate and deionized water, adding formaldehyde solution, adjusting the pH of the solution to 10, keeping the temperature at 99-101° C. for 170-190 minutes, cooling, concentrating, and drying to obtain hydroxymethylated lignin sulfonate; (2) heating the isopentyl polyoxyethylene ether until it is melted, adding boron trifluoride etherate and epichlorohydrin, keeping the temperature at 63-67°C for 110-130 minutes, and distilling under reduced pressure to obtain a chlorinated intermediate; mixing hydroxymethylated lignin sulfonate and deionized water, adjusting the pH to 13, adding the chlorinated intermediate, keeping the temperature at 75-85°C for 2-3 hours, adding to ethanol, concentrating, washing, and drying to obtain a lignin sulfonate-based polyether monomer; (3) Mixing lignin sulfonate-based polyether monomer, isopentyl polyoxyethylene ether, and deionized water, heating to 78-82° C., adding ammonium persulfate, stirring for 10-15 min, adding a mixed solution of acrylic acid, ascorbic acid, mercaptoethanol, and deionized water, keeping warm for 3-4 h, and adjusting the pH of the solution to 7 to obtain a composite lignin sulfonate; (4) Mix a polyhydroxy epicatechin derivative and dimethyl sulfoxide, add a mixed solution of N,N'-dicyclohexylcarbodiimide, 4-dimethylaminopyridine, dimethyl sulfoxide and composite lignin sulfonate, ultrasonically treat for 50-60 minutes, keep warm at 55-65°C for 22-24 hours, filter and wash with methanol for 3-5 times, and dry to obtain modified lignin sulfonate.

8. The high-dosage smelter slag-based super-sulfated cement for highway use according to claim 3, characterized in that: The auxiliary agent is prepared by compounding modified polydimethylsiloxane, isooctyl acrylate, tributyl phosphate and dihydroxydiethylamine in a mass ratio of (10-25): (15-25): (10-30): (30-50). The preparation of the modified polydimethylsiloxane includes the following steps: 1) Under nitrogen atmosphere, 1,2-epoxy-4-vinylcyclohexane, Karstedt catalyst and toluene are mixed, heated to 78-82°C, a mixture of hydrogen-terminated poly(dimethylsiloxane) and toluene is added, the temperature is raised to 98-102°C and kept for 11-12 hours, and vacuum distilled to obtain alicyclic epoxy polydimethylsiloxane; 2) Mix the polyhydroxy epicatechin derivative and dimethyl sulfoxide, raise the temperature to 65-75°C, add alicyclic epoxy polydimethylsiloxane and diethyl tetrafluoroborate, keep the temperature for 2-3 hours, add sodium carbonate, extract, and distill under reduced pressure to obtain modified polydimethylsiloxane.

9. A high-dosage smelter slag-based super-sulfated cement for highway use according to claim 7 or 8, characterized in that: The preparation of the polyhydroxy epicatechin derivative comprises the following steps: mixing epicatechin, p-hydroxybenzoic acid and methanesulfonic acid, transferring to a water bath at 38-42° C. and keeping warm for 110-130 minutes, cooling, pouring into an ice-water mixture, vacuum filtering, washing with a sodium bicarbonate solution and deionized water in sequence until the pH value is neutral, vacuum filtering, freeze drying, separating and purifying on a silica gel column using petroleum ether and ethyl acetate in a volume ratio of 3:1 as eluents, and rotary evaporating to obtain the polyhydroxy epicatechin derivative.

10. A method for preparing high-dosage smelting slag-based supersulfated cement for highway use according to any one of claims 1 to 8, characterized in that: The following steps are involved: Modified smelting slag powder, composite alkali slag powder, desulfurized gypsum, fly ash, iron tailings sand and water reducing agent are mixed and ball-milled to obtain a high-dosage smelting slag-based super-sulfate cement for highways.

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