The invention relates to the field of building material additives, in particular to a Protein Gypsum Retarder and a preparation method thereof.
The protein retarder is obtained by treating and modifying protein as a base. The peptide bonds in the retarder have strong metal ion complexing capability, and limit the diffusion of calcium ions to the hemihydrate gypsum, thereby reducing the dissolution rate of the hemihydrate gypsum. The action of retarders is directly related to their molecular weight and molecular structure. When the natural protein is directly used as a gypsum retarder, the effect is very limited, and the performance of the gypsum retarder can be improved by chemical modification. The gypsum retarder has strong hydrophilicity and is extremely easy to absorb moisture, and the problem that how to prepare retarder mother liquor into powder is difficult to solve is also solved.
In gypsum-based materials, gypsum retarders are a vital and indispensable additive. The retarder directly determines the operable time of the gypsum-based material in the construction or forming process, and has great influence on the strength of the hardened gypsum. The gypsum retarder can be mainly classified into organic retarder and inorganic retarder, wherein the organic retarder is mainly protein retarder, and the inorganic retarder mainly comprises citric acid, citrate, phosphate and the like. Compared with protein retarders, the inorganic retarders have a common retarding effect and have a large influence on the strength of the hardened gypsum. Therefore, the gypsum retarder on the market is mainly protein.
Gypsum, as one of the main traditional cementitious materials, has the following characteristics: (1) the setting and hardening are fast. (2) Light weight and good heat preservation and insulation performance. (3) Micro-expansion and micro-contraction. (4) The gypsum product has good processability, and the construction is quick and efficient. (5) The fire resistance is good. (6) The gypsum can be recycled, and the energy-saving effect is remarkable. In recent years, gypsum-based building materials have been rapidly developed, and the production of various gypsum-based mortars and gypsum products has been greatly increased year by year.
The protein gypsum retarder is powder, and has high uniformity and stable quality. And the powder has good fluidity, is easy to be uniformly dispersed without surfactant when producing the gypsum-based material.
Compared with the products in the prior art, the prepared protein gypsum retarder has strong retarding effect and the retarding performance is equivalent to that of the first-class products in the market. The universality is good, and the method is suitable for a desulfurized gypsum, phosphogypsum and gypsum-cement composite system. The side effect on the gypsum strength is small, and the gypsum strength loss rate is small along with the increase of the mixing amount of the retarder.
in the preparation method, the protein component is pretreated to be fully hydrolyzed to generate the amino acid with low molecular weight. The treated protein contains more amino groups, and the amino groups and carboxyl groups in organic acid are subjected to condensation reaction to generate more peptide bonds, so that the delayed coagulation effect of the protein is improved. The reaction solvent in the prior art is replaced by the quicklime and the diatomite, and the water generated by the reaction of the amino and the carboxyl is immediately absorbed by the quicklime and the diatomite, so that the chemical balance moves to the positive direction, and the reaction speed is accelerated. In the process of preparing the powder retarder, the vent valve of the reaction kettle is in an open state, and after the mixed liquid enters the reaction kettle, water is evaporated and discharged out of the reaction kettle under the conditions of high temperature and atomization. The solute of the mixed solution is uniformly sprayed on the continuously turned quicklime and diatomite and is uniformly mixed with the quicklime and the diatomite, so that the uniformity of the retarder is effectively improved.
Compared with the prior art, the preparation method of the protein gypsum retarder and the protein gypsum retarder prepared by the method have the following beneficial effects:
The invention also provides the protein gypsum retarder obtained by the preparation method of the protein gypsum retarder.
Preferably, the first reaction kettle and the second reaction kettle are both electrically heated autoclaved reaction kettles, and the gas outlet valve of the second reaction kettle is always in an open state.
Preferably, the quicklime is powdery, the content of calcium oxide is more than or equal to 85%, and the diatomite is not more than 400 meshes.
Preferably, the anti-caking agent is a mixture of 30-50 parts by mass of quicklime and 100-120 parts by mass of diatomite, and the mass ratio of the quicklime to the diatomite is 1: 2-1: 4.
Preferably, the protein component is one or a mixture of two or more of soybean protein isolate, industrial-grade bone glue or gelatin.
preparing a powder retarder: adding 150-160 parts by mass of an anti-caking agent into a second reaction kettle, opening an air outlet valve, heating to 150-170 ℃ while stirring, continuously stirring the reaction kettle, uniformly spraying the prepared mixed solution into the kettle within 2-3 h through an atomizer, continuously stirring for 3-4 h, taking out the materials, and sieving through a 100-mesh sieve to obtain the powder retarder.
preparing a mixed solution: adding 20-35 parts by mass of an acid substance into the protein solution, uniformly stirring until the acid substance is completely dissolved, and cooling to room temperature to obtain a mixed solution;
pretreatment of protein components: adding 100-120 parts by mass of water into a first reaction kettle, then adding 20-30 parts by mass of an alkali substance, stirring until the alkali substance is completely dissolved to form an alkali solution, heating the alkali solution to 80-90 ℃, adding 65-80 parts by mass of a protein component into the alkali solution, continuously stirring for 2-3 hours, and cooling to room temperature to obtain a protein solution;
In order to solve the technical problem, the invention provides a preparation method of a protein gypsum retarder, which comprises the following steps:
The technical problem to be solved by the invention is to provide the protein gypsum retarder which has strong retarding effect, good universality and small side effect on gypsum strength and the preparation method thereof, wherein the raw material components and the preparation process are simple.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the specific embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a preparation method of a protein gypsum retarder, which comprises the following steps:
pretreatment of protein components: adding 100-120 parts by mass of water into a first reaction kettle, then adding 20-30 parts by mass of an alkali substance, stirring until the alkali substance is completely dissolved to form an alkali solution, heating the alkali solution to 80-90 ℃, adding 65-80 parts by mass of a protein component into the alkali solution, continuously stirring for 2-3 hours, and cooling to room temperature to obtain a protein solution;
the protein component is soybean protein isolate, industrial bone glue or gelatin, and the soybean protein isolate has high protein content and is rich in various amino acids. The bone glue and the gelatin are both processed from animal protein and have wide application in the fields of printing and food processing respectively. Bone glue and gelatin are rich in a large amount of animal protein, and different kinds of amino acids can be obtained after hydrolysis.
The alkali substance is industrial-grade flake sodium hydroxide with the content being more than or equal to 99 percent, the soybean protein isolate, the bone glue and the gelatin can be hydrolyzed by strong alkali and strong acid, and the flake sodium hydroxide is commonly used industrial alkali and is easier to purchase.
The alkaline solution is heated to 80-90 ℃ to accelerate the hydrolysis of the protein component, water can boil when the temperature is too high, and the hydrolysis speed is not fast enough when the temperature is too low.
Preparing a mixed solution: adding 20-35 parts by mass of an acid substance into the protein solution, uniformly stirring until the acid substance is completely dissolved, and cooling to room temperature to obtain a mixed solution.
The acid substances are citric acid, fumaric acid or malic acid, the content of the acid substances is more than or equal to 99%, the acid substances all contain carboxyl, and the carboxyl can be subjected to condensation reaction with amino in amino acid to generate peptide bonds and realize grafting modification.
Preparing a powder retarder: adding 30-50 parts by mass of quicklime and 100-120 parts by mass of diatomite into a second reaction kettle, wherein the quicklime is powdery and is beneficial to uniformly mixing with the diatomite and reactants, and common diatomite usually does not exceed 400 meshes.
The air outlet valve of the second reaction kettle is in an open state, and after the mixed liquid enters the reaction kettle, water is evaporated and discharged out of the reaction kettle under the conditions of high temperature and atomization. If water is left in the reaction kettle, quicklime is consumed, and even the retarder is agglomerated. The solute of the mixed solution is uniformly sprayed on the continuously turned quicklime and diatomite and is uniformly mixed with the quicklime and the diatomite, so that the uniformity of the retarder is effectively improved.
The following examples further illustrate the above embodiments, but do not therefore limit the invention within the scope of the examples described. The experimental methods without specifying specific conditions in the following examples were selected according to the conventional methods and conditions, or according to the commercial instructions. Reagents, materials and equipment not specifically described are commercially available directly.
Example 1:
a preparation method of a protein gypsum retarder comprises the following steps of:
(1) pretreatment of protein components: adding 100 parts of water into the first reaction kettle, then adding 20 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. Heating the solution to 90 ℃, adding 65 parts of soybean protein isolate into the aqueous alkali, continuously stirring for 2h, and cooling to room temperature to obtain protein liquid.
(2) Preparing a mixed solution: adding 35 parts of citric acid into the protein solution, stirring uniformly until the citric acid is completely dissolved, and cooling to room temperature.
(3) Preparing a powder retarder: 50 parts of quicklime and 100 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 160 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the mixed solution obtained in the step (2) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 4h, taking out the material, and sieving through a 100-mesh sieve to obtain the powder retarder.
Example 2:
a protein gypsum retarder and a preparation method thereof, the specific preparation method comprises the following steps, the following components are added according to the parts by mass:
(1) pretreatment of protein components: adding 120 parts of water into the first reaction kettle, then adding 30 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. Heating the solution to 80 ℃, adding 80 parts of soybean protein isolate into the alkali solution, continuously stirring for 3h, and cooling to room temperature to obtain protein solution.
(2) Preparing a mixed solution: and adding 20 parts of citric acid into the protein solution, uniformly stirring until the citric acid is completely dissolved, and cooling to room temperature.
(3) Preparing a powder retarder: 30 parts of quicklime and 120 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 160 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the mixed solution obtained in the step (2) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 4h, taking out the material, and sieving through a 100-mesh sieve to obtain the powder retarder.
Example 3:
a protein gypsum retarder and a preparation method thereof, the specific preparation method comprises the following steps, the following components are added according to the parts by mass:
(1) pretreatment of protein components: adding 100 parts of water into the first reaction kettle, then adding 25 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. Heating the solution to 90 ℃, adding 70 parts of gelatin into the alkali solution, continuously stirring for 2h, and cooling to room temperature to obtain the protein solution.
(2) Preparing a mixed solution: and adding 30 parts of fumaric acid into the protein solution, uniformly stirring until the fumaric acid is completely dissolved, and cooling to room temperature.
(3) Preparing a powder retarder: 50 parts of quicklime and 110 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 170 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the mixed solution obtained in the step (2) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 3h, taking out the material, and sieving through a 100-mesh sieve to obtain the powder retarder.
Example 4:
a protein gypsum retarder and a preparation method thereof, the specific preparation method comprises the following steps, the following components are added according to the parts by mass:
(1) pretreatment of protein components: adding 110 parts of water into the first reaction kettle, then adding 30 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. And heating the solution to 90 ℃, adding 80 parts of gelatin into the alkali solution, continuously stirring for 2 hours, and cooling to room temperature to obtain the protein solution.
(2) Preparing a mixed solution: adding 20 parts of fumaric acid into the protein solution, stirring uniformly until the fumaric acid is completely dissolved, and cooling to room temperature.
(3) Preparing a powder retarder: 30 parts of quicklime and 120 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 150 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the mixed solution obtained in the step (2) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 4h, taking out the material, and sieving through a 100-mesh sieve to obtain the powder retarder.
Example 5:
a protein gypsum retarder and a preparation method thereof, the specific preparation method comprises the following steps, the following components are added according to the parts by mass:
(1) pretreatment of protein components: adding 110 parts of water into the first reaction kettle, then adding 30 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. Heating the solution to 90 ℃, adding 75 parts of gelatin into the alkali solution, continuously stirring for 2h, and cooling to room temperature to obtain the protein solution.
(2) Preparing a mixed solution: adding 25 parts of malic acid into the protein solution, stirring uniformly until the malic acid is completely dissolved, and cooling to room temperature.
(3) Preparing a powder retarder: 30 parts of quicklime and 120 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 160 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the mixed solution obtained in the step (2) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 4h, taking out the material, and sieving through a 100-mesh sieve to obtain the powder retarder.
Comparative example 1:
a protein gypsum retarder and a preparation method thereof, the specific preparation method comprises the following steps, the following components are added according to the parts by mass:
(1) pretreatment of protein components: adding 120 parts of water into the first reaction kettle, then adding 20 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. Heating the solution to 90 ℃, adding 100 parts of bone glue into the alkali solution, continuously stirring for 2h, and cooling to room temperature to obtain the protein solution.
(2) Preparing a powder retarder: 30 parts of quicklime and 120 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 160 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the protein liquid obtained in the step (1) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 4h, taking out the materials, and sieving through a 100-mesh sieve to obtain the powder retarder.
Comparative example 2:
a protein gypsum retarder and a preparation method thereof, the specific preparation method comprises the following steps, the following components are added according to the parts by mass:
(1) pretreatment of protein components: adding 120 parts of water into the first reaction kettle, then adding 30 parts of flaky sodium hydroxide, and stirring until the flaky sodium hydroxide is completely dissolved to form an alkali solution. Heating the solution to 120 ℃, adding 80 parts of bone glue into the alkali solution, and continuously stirring for 2 hours to obtain the protein solution.
(2) Preparing a powder retarder: 30 parts of quicklime and 120 parts of kieselguhr are added into a second reaction kettle, a gas outlet valve is opened, and the mixture is heated to 160 ℃ while stirring. And (3) continuously stirring in a second reaction kettle, uniformly spraying the protein liquid obtained in the step (1) into the second reaction kettle within 2-3 h through an atomizer, continuously stirring for 4h, taking out the materials, sieving with a 100-mesh sieve, and uniformly mixing with 20 parts of citric acid.
The performance of the gypsum retarders prepared in the comparative examples 1 to 5 and the comparative examples 1 to 2 is tested by referring to GB/T17669.4-1999 determination of physical properties of clean slurry of building gypsum and GB/T17669.3-1999 determination of mechanical properties of building gypsum, and the specific results are shown in Table 1:
TABLE 1
As can be seen from Table 1, the retarder in the examples of the present invention has the characteristics of strong retarding effect, small side effect on the strength of gypsum, etc.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
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