85 results about "Hemihydrate" patented technology

This invention belongs to the technical field of medicinal chemistry, specifically relating to a novel crystal form of cariprazine, specifically the cariprazine-4-hydroxybenzoic acid-methanol-hemihydrate crystal form and its preparation method. The novel cariprazine-fumaric acid crystal form provided by this invention comprises a basic unit of one molecule of cariprazine, one molecule of 4-hydroxybenzoic acid, one molecule of methanol, and 0.5 molecules of water. Its preparation method is simple to operate, the crystallization process is easy to control, and it has good reproducibility. The formation of a eutectic significantly enhances the solubility of cariprazine, exhibiting strong pharmaceutical value.

The invention discloses an efficient retarding and strength-retaining composite retarding formula and application of the efficient retarding and strength-retaining composite retarding formula in alpha-semi-hydrated gypsum, and the composite retarding formula is prepared from the following raw materials in parts by weight: 0.01 to 0.06 part of sodium tripolyphosphate, 0.02 to 0.08 part of a retarding auxiliary agent and 0.01 to 0.04 part of a reinforcing agent; the retarding auxiliary agent is a composition of protein substances and carbohydrates. The composite retarding formula developed by the invention has a synergistic effect, aims to realize efficient retarding under a low mixing amount, meanwhile, the used raw materials are low in price and easy to obtain, the operation is simple and convenient, and the composite retarding formula shows a wide prospect for high-valued application of alpha-HH.

The application discloses a kind of phosphoric acid extraction semi-water-two water alternate crystallization system and method, belong to the technical field of wet-process phosphoric acid production, the system is by the reaction tank unit of series connection and semi-water and two water reaction tank alternate arrangement, with the sulfuric acid dilution mixed heat exchanger group connected with reaction tank, simple heat exchanger group is arranged between tank to realize heat transfer.Construction.The method includes: material is temperature-adjusted after passing through sulfuric acid dilution mixed heat exchanger, in turn into the reaction tank sequence of alternate arrangement, heat circulation is carried out in adjacent tank by simple heat exchanger, under the control of PLC in 75~85 DEG C and 88~95 DEG C interval, realize the alternate crystallization of semi-water-two water calcium sulfate.The application replaces traditional flash evaporation external discharge with heat internal circulation between tank, solves the technical problems of high steam energy consumption, low phosphorus recovery rate, insufficient phosphoric acid concentration and high upgrading cost of stock device in traditional process, and has the comprehensive advantages of energy saving, yield, low-cost transformation and phosphogypsum resource.

A method for producing phosphoric acid, comprising attack in an aqueous medium of phosphated rock with sulfuric acid, with formation of a first dihydrate slurry suspended in an aqueous phase having a free P2O5 content between 38 and 50% and a free SO3 content of less than 0.5%, conversion of this first slurry by heating with recrystallization of the solubilized calcium sulfate giving rise to a second hemihydrate slurry, and separation in the second slurry between a production phosphoric acid and a hemihydfate cake, characterized in that it comprises'during the attack, addition of a fluorine source in the first slurry in a content from 1 % to 5% by weight of F relatively to the P2O5 contained in the phosphated rock.

The invention provides a mesoporous gypsum block and a preparation method thereof, and relates to the technical field of building materials and novel wall materials, the mesoporous gypsum block is prepared from the following raw materials by weight: 35-65 parts of hemihydrate gypsum, 40-60 parts of anhydrous II gypsum, 1.5-2.5 parts of nano mesoporous silica or modified nano mesoporous silica, 0.1-0.15 part of a polycarboxylic acid water reducer, 2-5 parts of a fiber reinforced material, and 90-150 parts of water. According to the invention, nano mesoporous silica is selected as a hard template agent and is compounded with two kinds of biphase gypsum, i.e., semi-hydrated gypsum and anhydrous II gypsum, so that the mesoporous gypsum block is generated, and the mesoporous gypsum block has a relatively strong pore skeleton structure and relatively good thermal stability, and has more excellent heat insulation performance compared with a traditional heat insulation material; energy is saved, consumption is reduced, space is saved, auxiliary materials are saved, and the service life is long.

An underlayment material composition is disclosed that includes a binder, a filler, a polymer, and a retarder. The binder includes calcium sulphate alpha hemihydrate, the filler includes cork, the polymer includes superplasticizer, and the retarder includes modified amino acid. The underlayment material exhibits a thermal resistance value that exceeds a threshold value for a defined thickness value. Further, a method of using the underlayment material composition in non-structural applications of one or more construction-related activities includes mixing the underlayment material composition, that includes the binder, the filler, the polymer, and the retarder, with a defined amount of water for a defined amount of time to produce an underlayment material composition mix having a defined consistency. The method further includes applying a coat of the underlayment material composition mix on a primer-coated surface.

According to a first aspect, the invention relates to a process for the production, preferably continuous, of calcium sulfate alpha hemihydrate, the process comprising: - the preparation of an aqueous gypsum suspension comprising gypsum in particulate form, water and at least one superplasticizing polymer selected from phosphate polyethers, sulfonated melamine formaldehyde (SMF) and sodium poly(styrene sulfonate); - the calcination of the aqueous gypsum suspension at a suitable temperature and pressure to obtain a suspension of calcium sulfate alpha hemihydrate; - optionally, the filtration of the calcium sulfate alpha hemihydrate suspension to separately obtain a concentrated alpha hemihydrate suspension and an aqueous filtrate.The invention also relates, according to a second aspect, to a process for preparing a gypsum-based product comprising the preparation of a plaster suspension comprising calcium sulfate alpha hemihydrate obtained by the process according to the invention. Furthermore, the invention relates to a plaster-based product obtained using a process according to the invention. The invention also relates to a gypsum-based product obtained using a process according to the invention, such as a plasterboard. Figure 2.

The application discloses a kind of phosphogypsum solid waste's step-by-step modification calcination preparation method, belong to solid waste treatment technical field.The method includes: (1) pre-coating treatment: the original state of containing attached water dihydrate phosphogypsum is mixed with composite modifier and is ground, and pre-coated phosphogypsum is obtained;(2) temperature control calcination: the pre-coated phosphogypsum obtained in step (1) is sent into calcining kiln, and dehydration reaction is carried out at 165 DEG C~180 DEG C temperature, and hemihydrate gypsum powder is obtained;(3) hygroscopic aging: the hemihydrate gypsum powder obtained in step (2) is cooled and aged 24h~48h, and the components in powder are used to absorb moisture in air to carry out hydration reaction, and the final product is obtained.The method is free of water washing, short process, and the obtained phosphorus building gypsum standard consistency water consumption is 45%~50%, and 2 hour compressive strength is greater than or equal to 6.5MPa.

This invention discloses a method for purifying and classifying low-quality, compacted phosphogypsum to prepare building materials, comprising the following steps: 1) feeding low-quality, compacted phosphogypsum into a ceramic ball mill for grinding to obtain phosphogypsum slurry; 2) feeding the phosphogypsum slurry into an ultrasonic cleaner for ultrasonic vibration cleaning; 3) obtaining a foam product as high-silica tailings and an underflow product as high-purity phosphogypsum slurry; 4) feeding the high-silica tailings into a filter for filtration, and then adding fly ash and an alkali activator to the filtered high-silica tailings to obtain a phosphogypsum-based polymer; 5) filtering the high-purity phosphogypsum slurry through a filter, drying it in an oven, and finally calcining it in a calcining furnace to obtain high-quality β-hemihydrate gypsum powder. This invention is simple and feasible, and particularly effective in purifying low-quality phosphogypsum with many impurities and severe compaction, without generating secondary solid waste. It also provides a reasonable and reliable full-scale application technology route for the resource utilization of low-quality, compacted phosphogypsum.

The invention relates to the field of gypsum-based building materials, and particularly discloses a preparation method of a lysine-tannic acid compound retarder and a gypsum-based building material.The preparation method comprises the following steps that 1, tannic acid and copper acetate are added into water to be stirred, and a copper-tannic acid pre-coordination solution is obtained; then adding L-lysine into the mixture, and stirring for reaction to obtain precursor liquid after the reaction is completed; and (2) adding glyoxal into the precursor liquid for reaction, and then adding dialdehyde polyethylene glycol for continuous reaction to obtain the compound retarder. The gypsum-based building material comprises the following components: alpha-semi-hydrated gypsum, cement, slag powder, the lysine-tannic acid compound retarder, a water reducing agent and mixing water. The retarder provided by the invention not only has a good retarding effect on the gypsum-based building material, but also can improve the early strength of the gypsum-based building material, and effectively overcomes the contradictory problem of retarding and early strength.

The application discloses a kind of thermal insulation wall repair materials and preparation method thereof.The thermal insulation wall repair material of the application includes the following components by weight parts: modified burnt magnesium oxide 125-166 parts, ammonium dihydrogen phosphate 120-165 parts, fly ash floating bead 72-105 parts, water glass 20-55 parts, steel slag powder 25-55 parts, aluminum powder 18-40 parts, alpha-hemihydrate gypsum 10-40 parts, xanthan gum 15-45 parts, water 185-286 parts.The application fuses surface modification technology, polymer enhancement technology and the like, so that the modified magnesium oxide particles have good fluidity, controllable setting time in the later hydration process, and can improve the bonding performance of the material in the later period.After fully mixing modified burnt magnesium oxide, ammonium dihydrogen phosphate, mixed mineral admixture, water glass and foaming agent, the prepared thermal insulation wall repair material has high permeability, high fluidity, high cohesiveness, operability, and prolongs the service life of the thermal insulation wall.

This invention discloses a synthetic gypsum and gypsum boards produced therefrom. Limestone (Calcium Carbonate), slaked lime (calcium hydroxide), water, and sulfuric acid are mixed, and alpha hemihydrate gypsum is optionally added as crystal seed to produce synthetic gypsum. The synthetic gypsum is then used to make gypsum boards. The gypsum board produced according to this invention contains at least 10% alpha hemihydrate gypsum.

The application discloses a method for extracting phosphorus and reducing aluminum in a hemihydrate-dihydrate wet-process phosphoric acid process, and belongs to the technical field of the wet-process phosphoric acid. The method is characterized in that: after phosphorite and return acid are uniformly mixed, hemihydrate acidolysis reaction is carried out in the presence of concentrated sulfuric acid, a mixed slurry of stable hemihydrate calcium sulfate crystals and intermediate acid is obtained, then a hydroxyquinoline compound is added, and after continuous reaction, hemihydrate gypsum and intermediate acid with low Al2O3 content can be obtained by filtration; dihydrate gypsum can be obtained by carrying out dihydrate conversion reaction of the hemihydrate gypsum in the presence of concentrated sulfuric acid. The method couples a chemical precipitation method in the hemihydrate-dihydrate wet-process phosphoric acid acidolysis process, can reduce the Al2O3 content in the intermediate acid by the chemical precipitation method, the generated precipitate can be filtered together with the phosphogypsum, and the separation of impurities is easy to realize; meanwhile, the generated precipitate can promote crystal growth in the dihydrate conversion reaction of the hemihydrate gypsum, uniform and bulky dihydrate calcium sulfate crystals are obtained, the washing and filtering performance of the filter cake is improved, and the phosphorus yield is increased.

The application discloses a desulfurization gypsum dechlorination and quality improvement process system and belongs to the technical field of alpha hemihydrate gypsum production. In the material step-by-step drying system of the process, the material outlet of a reaction device is communicated with the material inlet of a high-pressure slurry separation and dehydration device, the material outlet of the high-pressure slurry separation and dehydration device is communicated with the material inlet of a flash device, the material outlet of the flash device is communicated with the material inlet of a high-temperature drying device, and the separation steam outlet of the flash device is communicated with the steam inlet of a solid-liquid mixing device. The separation water outlet of the high-pressure slurry separation and dehydration device is communicated with the high-pressure inlet of a multi-stage water circulation system, the separation water outlet of the flash device is communicated with the steam inlet of a raw material reaction system, and the separation water outlet of the high-temperature drying device is communicated with the low-pressure inlet of the multi-stage water circulation system. The process reduces system energy consumption through a step-by-step drying method, effectively utilizes drying water with different pressures through a multi-stage water circulation system, and reduces system heat loss through heat recovery.

This disclosure pertains to the field of phosphogypsum technology, specifically relating to a hemihydrate phosphogypsum gel material, its preparation method, and its applications. The gel material is prepared using hemihydrate phosphogypsum, an alkaline activator, and a water-reducing agent. This reduces water consumption while achieving a good retarding effect. By introducing silicate compounds and crystal form regulators with succinic acid groups and silane groups, the synergistic effect of these compounds and regulators provides a cementing network for the dihydrate phosphogypsum crystals, increasing bonding strength and thus improving the strength of gypsum products. Therefore, the hemihydrate phosphogypsum gel material provided by this disclosure maintains the mechanical properties of the gel material while reducing water consumption and extending setting time.

The application relates to the technical field of paint, in particular to a low-cost dry powder paint special for alcohol-based casting and a preparation method thereof, which comprises the following raw materials in parts by weight: 40-60 parts of mica powder, 20-40 parts of attapulgite, 10-20 parts of kaolin, 2-4 parts of polyvinyl butyral, 4-6 parts of powder, 6-10 parts of additives, and 4-6 parts of bauxite. In the application, solid waste red mud is used as a binder core base material, the surface inert oxide layer of the red mud is stripped through oxalic acid solution activation, the high-activity silicate-aluminate porous framework is exposed, the low-cost bonding system with a three-dimensional network structure is constructed through ball milling and calcium lignosulfonate / temperature-sensitive monomer composite modification, and the bonding durability is enhanced through the ion crosslinking effect of beta-hemihydrate gypsum and magnesium olivine in the mixture. The comprehensive performance of the dry powder paint is ensured, the solid waste replaces traditional high-price silica sol and resin and other raw materials, and the raw material cost is significantly reduced.

The present application relates to low-cost high-value comprehensive utilization of high-iron gypsum, and relates to a method for deep iron removal of high-iron gypsum, in particular to a method for deep iron removal of high-iron gypsum and preparation of high-quality high-value gypsum at the same time. The present application firstly removes part of iron in titanium gypsum through acid leaching treatment, then fully releases iron impurities inside gypsum inclusions and intergranular gaps through a dissolution process of gypsum phase regulation, simultaneously regulates the existing form of iron in the solution to avoid its entering into the gypsum lattice in the process of recrystallization, and adjusts the morphology and particle size of the recrystallization product by adding a crystal form regulator to weaken the adsorption of iron on the surface of the gypsum product, finally realizes the efficient separation of iron and gypsum product by releasing iron and weakening the adsorption effect of iron, and forms high-purity high-strength alpha-hemihydrate gypsum. The present application realizes the effective combination of deep iron removal in high-iron gypsum and the preparation process of high-quality high-value gypsum product.

This invention relates to the field of support materials and discloses a method for preparing a rapid-hardening dry powder support material for underground coal mines. The method includes: uniformly mixing 40%-50% sulfoaluminate cement, 10% slag powder, and 40%-50% hemihydrate gypsum to form a ternary mixed dry powder; mixing 0.5%-2% of a composite early-strength agent (by mass of sulfoaluminate cement) with 4% of a quick-setting agent (by mass of total dry powder), and adding this mixture along with water to the dry powder while stirring for 30 seconds to obtain an initial slurry; then adding 2.5%-4% of a composite expansion agent (by mass of sulfoaluminate cement) and 0.5%-2% of a composite activator (by mass of slag powder) to the slurry, and continuing high-speed stirring for 3 minutes; finally, pouring the mixture into a mold, allowing it to stand, demolding, and curing. This invention, by constructing a ternary cementitious system and combining it with specific additives and a segmented mixing process, balances the early-stage setting, volume compensation, and later-stage strength development of the material, enabling the support material to possess both rapid setting and long-term structural stability.

The application discloses an injectable and plastic composite bone powder material for dental implant and a preparation and application thereof, and comprises the following components in parts by mass: 1-5 parts of bone powder, 0.1-1 parts of decellularized extracellular matrix and 5 parts of calcium sulphate hemihydrate. The bone powder provides a porous three-dimensional structure with a natural bone structure and suitable new bone growth and bone inductivity. The decellularized extracellular matrix provides a three-dimensional framework containing extracellular matrix macromolecules, can promote rapid proliferation and adhesion of cells, and serves as a biomimetic mineralization template. The calcium sulphate hemihydrate provides good degradation time, injectability and in-situ plastic shaping and curing properties for the whole composite material. The three components are combined, so that the material is provided with good injectability and plasticity, and a biomimetic microenvironment with bone inductivity is constructed.

The present application relates to the technical field of inorganic non-metallic materials, and particularly relates to a gypsum-based cementing material and a preparation method thereof, the gypsum-based cementing material comprising the following components in percentage by mass: 25-50% of type 2 anhydrite powder, 10-30% of hemihydrate gypsum powder, 10-20% of cement clinker powder, 20-25% of active micro powder, 3-5% of quicklime, and 1-5% of an activator. The gypsum-based cementing material of the present application is based on type 2 anhydrite and hemihydrate gypsum, and cement clinker powder is added thereto, so that the hydration performance of the cementing material can be significantly improved; the active micro powder and quicklime powder are further added, so that the cementing structure of the cementing material can be improved, a multi-element cementing system is formed, and the stability and durability of the cementing system are significantly improved; and the activator is further added, so that a calcium aluminate cementing body can be quickly formed during the hydration of the cementing material, the hydration conditions are further optimized, and the gypsum-based cementing material is more suitable for construction.

The invention discloses a method for efficiently recovering and recycling salt in sulfuric acid method titanium dioxide production, which comprises the following steps: S1, pretreating salt-containing wastewater generated in sulfuric acid method titanium dioxide production to remove solid particles in the wastewater; s2, salt in the wastewater is concentrated, and the ion proportion and pH in the concentrated solution are adjusted; s3, concentrating and crystallizing to obtain aluminum potassium sulfate dodecahydrate solid; s4, dehydrating the aluminum potassium sulfate dodecahydrate solid to obtain aluminum potassium sulfate hemihydrate; and S5, grafting the aluminum potassium sulfate hemihydrate with a water-soluble high-molecular compound containing an active functional group to obtain the flocculating agent. According to the method, the salt recovery rate and purity can be remarkably improved, the energy consumption is reduced, and efficient cyclic utilization of the recovered salt is realized.

A system for manufacturing gypsum-based products via a wet calcination method is provided. The system includes a mixing stage for providing gypsum slurry, a reactor stage for calcining the gypsum slurry into an α-hemihydrate slurry, and a dehydration stage for removing water from the α-hemihydrate slurry. Water is removed as liquid water and steam. The liquid water is recycled back to the mixing stage as a water source. The latent heat and sensible heat of the steam are used as a heating source for the system to reduce the energy requirement for heating within the system.

This application provides a method for preparing α-hemihydrate gypsum using desulfurized gypsum. The method involves mixing desulfurized gypsum with salt production effluent, then introducing air to allow the calcium carbonate and calcium chloride in the desulfurized gypsum to react with the effluent to form calcium sulfate, while simultaneously oxidizing calcium sulfite to calcium sulfate. After a period of time, the mixture is placed in an autoclave with a certain amount of crystallizing agent added and stirred thoroughly. After the reaction is complete, the mixture is immediately filtered, dried, and ground to obtain α-hemihydrate gypsum. The method for preparing α-hemihydrate gypsum using desulfurized gypsum provided in this application can improve the conversion rate of desulfurized gypsum to α-hemihydrate gypsum and meets the requirements of a green economy, thus possessing significant economic and environmental benefits.

This utility model relates to the field of chemical reaction technology, and in particular to a system for producing wet-process phosphoric acid and α-hemihydrate gypsum from phosphate rock, comprising: a reaction tank; a sulfuric acid inlet to the reaction tank; a crystallization tank connected to a first slurry outlet of the reaction tank; a sulfuric acid inlet to the crystallization tank; a dihydrate filter connected to a second slurry outlet of the reaction tank; a dihydrate gypsum outlet of the dihydrate filter connected to the dihydrate gypsum inlet of the crystallization tank; a hemihydrate gypsum filter connected to the slurry outlet of the crystallization tank; a washing water inlet to the hemihydrate gypsum filter; and a hemihydrate gypsum drying system connected to the hemihydrate gypsum outlet of the hemihydrate gypsum filter. This application, by adding a small amount of equipment to a dihydrate phosphoric acid production unit, can improve the extraction rate of wet-process phosphoric acid and co-produce hemihydrate gypsum, resulting in a system for producing wet-process phosphoric acid and α-hemihydrate gypsum from phosphate rock with a high total phosphorus yield, low phosphate rock consumption, and low energy consumption.

The invention provides a high-durability anhydrous-semi-hydrated phosphogypsum phosphorus slag curb and a preparation method of the high-durability anhydrous-semi-hydrated phosphogypsum phosphorus slag curb. The curb is prepared by taking ardealite and phosphorus slag industrial solid waste materials as main raw materials, so that the problems of insufficient early strength, high water absorption rate, poor durability, poor crack resistance, low fluidity, high cost and the like of the traditional curb are solved. The invention also provides a preparation method of the high-durability anhydrous-semi-hydrated phosphogypsum phosphorus slag kerb.

This invention discloses a novel crystalline form of tanshinone hemihydrate, its preparation method, and its applications, belonging to the fields of microbial fermentation and crystallization technology. The crystalline form of this invention, as determined by X-ray powder diffraction, infrared analysis, melting point determination, and nuclear magnetic resonance, is significantly different from the crystalline form of tanshinone in existing technologies. The novel crystalline form of tanshinone hemihydrate prepared by this invention exhibits solubility exceeding 580 mg / mL in water and organic solvents, along with excellent chemical stability and purity. It is easy to prepare on a large scale, simple to operate, and has broad application prospects.

The invention relates to the technical field of building materials, and discloses light plastering gypsum as well as a preparation method and application thereof. The light plastering gypsum is prepared from the following raw material components: desulfurized gypsum powder, modified small yellow sand, ground calcium carbonate, modified bentonite, superfine fly ash, a composite water-retaining agent, a composite retarder and a thixotropic agent, wherein the desulfurized gypsum powder comprises the following three phases in percentage by mass: less than or equal to 2.8% of residual dihydrate gypsum, less than or equal to 2.5% of anhydrous gypsum and more than or equal to 78% of semi-hydrated gypsum; the composite water-retaining agent is formed by compounding hydroxypropyl methyl cellulose ether and guar gum; the composite retarder is formed by compounding sodium citrate and tartaric acid. The preparation method is simple and efficient, conditions are controllable, the prepared light plastering gypsum is light, the volume density is smaller than or equal to 860 kg / m < 3 >, after construction, the anti-sagging performance is high, the strength is high, the water retention rate reaches up to 94%, and the retarding effect is excellent.

The invention discloses a method for preparing an efficient cement retarder by rapidly hydrating semi-hydrated phosphogypsum and application of the efficient cement retarder, and belongs to the technical field of preparation of cement retarders. A composite fluorosilicone material and by-product fluorosilicone waste liquid are used as rapid hydrating agents, semi-hydrated phosphogypsum is rapidly hydrated, semi-hydrated phosphogypsum crystals are converted into dihydrate phosphogypsum crystals in an acid environment, and after aging is conducted at the normal temperature, the efficient retarding cement retarder is obtained. The problem that semi-hydrated phosphogypsum is difficult to be used as a raw material for producing the high-efficiency delayed-setting cement retarder is solved, and meanwhile, a new way is found for consumption of a byproduct composite fluorosilicone material and a byproduct fluorosilicone waste liquid in phosphorus and fluorine chemical enterprises.

The invention discloses ceramic mold gypsum with industrial byproduct semi-hydrated gypsum as a base material and a preparation method thereof.The ceramic mold gypsum is prepared from, by mass, 75%-85% of alpha-semi-hydrated gypsum and 15%-25% of power plant fire coal waste, the alpha-semi-hydrated gypsum is prepared from the industrial byproduct semi-hydrated gypsum, and the technical parameters of the alpha-semi-hydrated gypsum are as follows: the standard thickness is 40%-45%, the initial setting time is 16-22 minutes, and the wet fracture resistance is 6.0-6.5 Mpa in two hours. Alpha-semi-hydrated gypsum prepared from industrial by-product gypsum is taken as a basis, power plant fire coal waste in a specific proportion is doped, the two materials are uniformly mixed, water is added, the ceramic mold gypsum (powder) is obtained, the strength requirement and the water absorption requirement of the ceramic mold gypsum are met, and compared with natural gypsum ceramic mold (powder), the ceramic mold gypsum has obvious cost advantage and environmental protection advantage.

The invention discloses a ceramic tile adhesive taking alpha-two-phase gypsum as a main cementing material and a preparation method thereof, the ceramic tile adhesive comprises alpha-two-phase gypsum, a composite water reducer and dihydrate gypsum, the alpha-two-phase gypsum comprises 35-65% of alpha-semi-hydrated gypsum and 65-35% of alpha-anhydrite II; the adding proportion of the composite water reducing agent is 0.01%-0.2% of the mass of the alpha-two-phase gypsum, and the composite water reducing agent is prepared from lignosulfonate and melamine according to the mass ratio of (1-2): 1. The adding proportion of the dihydrate gypsum is 0.5%-1.0% of the mass of the alpha-two-phase gypsum. The preparation method comprises the following steps: uniformly mixing all the preparation material components, adding water according to the standard consistency, and stirring to form jelly for use. The gypsum-based ceramic tile adhesive with alpha-two-phase gypsum as the main cementing material is free of organic rubber powder, free of dry shrinkage, few in variety of auxiliary materials in the formula, simple to prepare and high in adhesive force to ceramic tiles, is used for smooth surfaces of the ceramic tiles and even has good adhesive force on glass surfaces, meanwhile, can quickly generate adhesive strength, is controllable in setting time, and can be used for preparing the ceramic tiles. The maintenance period is short, and the construction period is greatly shortened.