New generation triisopropanol amine monoacetate based grinding aid with high grinding efficiency, strength enhancer

Abstract

The present invention relates to the grinding aid used in the cement industry, in the clinker grinding phase of cement production and in the preparation of cementitious systems. In particular, the present invention relates to the grinding aid and synthesis method consisting of the Triisopropanol amine monoacetate composition obtained as a result of the esterification reaction of Triisopropanol amine with acetic acid.

Description

[0001] New Generation Triisopropanol Amine Monoacetate Based Grinding Aid With High Grinding Efficiency, Strength Enhancer

[0002] Field of the Invention

[0003] The present invention relates to the grinding aid used in the cement industry, in the clinker grinding phase of cement production and in the preparation of cementitious systems. In particular, the present invention relates to the grinding aid and synthesis method consisting of the Triisopropanol amine monoacetate composition obtained as a result of the esterification reaction of Triisopropanol amine with acetic acid.

[0004] State of the Art

[0005] Events such as greenhouse gas emissions, air pollution and climate change are among the main factors that cause global problems. In the process of solving these problems, issues such as developing alternatives to products that cause CO2 emissions during production, renewable energy sources and energy efficiency have gained importance.

[0006] The cement industry causes great damage to the environment in terms of energy, raw material consumption and CO2 emissions. The amount of electricity consumed in the cement industry constitutes 2% of the electricity used worldwide and 5% of the electricity used in industry. However, it accounts for 5-7% of global CO2 emissions. While approximately 1 ,2 tons of raw materials and 130 kWh of energy are consumed to produce one ton of cement, approximately 1 ton of CO2 is produced as a result. According to the Paris climate agreement, greenhouse gas emissions are expected to be reduced by 50% in 2030 and completely to zero in 2050. In this regard, energy efficiency is of great importance in the production processes of products that cause greenhouse gas emissions during production.

[0007] In cement production, approximately 35% of the energy consumed is spent in the clinker grinding phase. In addition, a significant part of the energy consumed in the grinding stage is wasted by turning into heat, sound and vibration. As a result of the studies carried out to reduce both the energy consumption and cost in question and to reduce the amount of CO2 emitted to the environment, the use of grinding aid (GA) has come to the agenda.

[0008] GAs are adsorbed on the surfaces of grains with the help of high polarity functional groups (-OH, -NH2, -COOR, -SO3 etc.) they contain. Adsorbed GAs neutralize the electrical charges on the surface, preventing the cracks formed in the clinker from closing, preventing the particles from coming together and sticking to the mill surface and / or balls, thus ensuring grinding efficiency.

[0009] It is known that the cement grains produced by the use of GA have different surface energy even though they have the same Blaine fineness value. This situation significantly affects the hydration reactions of cement and cement-additive compatibility. In addition, it has been explained that cements produced by GA consist of smaller and smoother / angular-free grains. This situation may bring with it some negativities.

[0010] In the present art, cement grinding aids are typically selected from the class containing glycols, amines, or amino alcohols, such as alkylene glycols. For example, the grinding aid mentioned in European patent EP3019455B1 comprises at least one aminoalcohol and at least one substance selected from chlorides, thiocyanates, nitrates, nitrites and hydroxides which accelerate cement hydration and the concrete admixture comprises a reaction product of at least one calcium compound with at least one silicon compound selected from a silicon dioxide compound, a silica compound and a silicate compound.

[0011] However, with the developing technology, it has been determined that the performances of the existing GAs are insufficient and there is a significant gap in their development.

[0012] As a result due to the abovementioned disadvantages and the insufficiency of the current solutions regarding the subject matter, a development is required to be made in the relevant technical field. Purpose of the Invention

[0013] The present invention aims to solve the abovementioned disadvantages by being inspired from the current conditions.

[0014] The purpose of the present invention is to provide a new grinding aid with improved grinding performance by changing one or two of the hydroxyl groups in the commercially widely used Triisopropanol amine (TIPA) as a result of esterification reaction with organic acid, forming an ester of higher polarity.

[0015] Another purpose of the invention is to provide a grinding aid containing Triisopropanol amine monoacetate obtained as a result of the esterification reaction of Triisopropanol amine with acetic acid, thereby increasing the grinding performance and cement system properties of the TIPA used as a GA, while reducing the cost of the admixture.

[0016] In order to fulfill the aforementioned purposes, the invention is a new generation grinding aid with high grinding efficiency, strength enhancer, and comprises Triisopropanol amine monoacetate obtained by esterification reaction of Triisopropanol amine with acetic acid.

[0017] According to one embodiment, the invention may also contain Triisopropanol amine.

[0018] According to one embodiment of the invention may comprise 40% Triisopropanol amine and 60% Triisopropanol aminemono acetate by weight.

[0019] In order to fulfill the purposes described above, the invention is a new generation grinding aid synthesis method with high grinding efficiency, strength enhancer, characterized by comprising the following process steps; i. evaporating of its water by heating triisopropanol amine; ii. Lowering the temperature of the heated triisopropanol amine to 50-60 degrees Celsius and adding half of the acetic acid dropwise; iii. Then, heating again and adding catalyst before the temperature reaches 80 degrees Celsius; iv. Adding the remaining acetic acid dropwise; v. Continuing the reaction at approximately 1 10-120 degrees Celsius and removing the water formed with the ester by applying vacuum repeatedly after the second hour.

[0020] According to an embodiment of the invention, 65-85% Triisopropanol amine, 15-25% Acetic acid and 1 -3% catalyst by weight can be used in the synthesis method.

[0021] According to an embodiment of the invention, 78% Triisopropanol amine, 20% Acetic acid and 2% catalyst by weight can be used.

[0022] According to one embodiment of the invention, sulfuric acid can be used as the catalyst.

[0023] According to one embodiment of the invention, the reaction can be continued at about 1 15 degrees Celsius.

[0024] According to one embodiment of the invention, the reaction can be continued for 3 hours.

[0025] According to an embodiment of the invention, after the second hour of the reaction, vacuum is applied every 15 minutes and the water formed with the ester is removed.

[0026] The structural and characteristic features of the present invention will be understood clearly by the following figures and the detailed description made with reference to these figures and therefore the evaluation shall be made by taking these figures and the detailed description into consideration.

[0027] Figures to Help Understanding the Invention

[0028] Figure 1 .a. TIRA, 1 b. theoretical modeling of the M-TIPA of the present invention.

[0029] Figure 2. FTIR analysis result graph of M-TIPA of the present invention.

[0030] Figure 3. GC-MS chromatogram of the M-TIPA molecules of the present invention and the TIPA.

[0031] Figure 4. Mass spectrum of the product arriving at 18,5 minutes in the chromatogram

[0032] Figure 5.13C NMR spectrum of the M-TIPA molecule of the present invention.

[0033] Figure 6.13C NMR spectrum of acetic acid suggested by the chemdraw program. Figure 7.13C NMR spectrum of TIRA molecule suggested by the chemdraw program.

[0034] Figure 8. Relative grinding efficiencies graph of TIPA and M-TIPA.

[0035] Figure 9. Relative flow and consistency retention performance graph.

[0036] Detailed Description of the Invention

[0037] In this detailed description, the inventive modified TIPA-containing grinding aid and preferred embodiments thereof are described only for a better understanding of the subject matter.

[0038] The invention relates to a new generation Triisopropanol amine monoacetate based grinding aid and synthesis method, which is obtained as a result of esterification reaction of Triisopropanol amine with acetic acid.

[0039] The Triisopropanol amino acetate based grinding aid production method, which is the subject of the invention, comprises the process steps of; i. evaporating of its water by heating triisopropanol amine; ii. Lowering the temperature of the heated triisopropanol amine to 50-60 degrees Celsius and adding half of the acetic acid dropwise; iii. Then, heating again and adding catalyst before the temperature reaches 80 degrees Celsius; iv. Adding the remaining acetic acid dropwise; v. Continuing the reaction at 1 10-120 degrees Celsius and removing the water formed with the ester by applying vacuum repeatedly after the second hour.

[0040] In the method of the invention, the presence of process step (i) is necessary to increase the degree of realization of the reaction. Since water is formed as a result of esterification, the presence of water in the environment affects the degree and speed of the reaction. TIPA boiling point is 299 C. Heating up to 100 C can be done to remove water. In the process step (ii) of the method of the invention, if acetic acid is suddenly added, a titration reaction may occur. That's why it should be added slowly. Acetic acid should not be added when the temperature of TIPA is above 80 degrees. Chemicals added to the reactor should be added dropwise.

[0041] In the process step (iii) of the method of the invention, the highest efficiency was achieved when sulfuric acid was used as the catalyst. In order for sulfuric acid to function as a catalyst, the temperature should not exceed 80 degrees at the time of addition.

[0042] In the process step (iv) of the method of the invention, the remainder of the acetic acid is added slowly in order for the esterification reaction to occur successfully.

[0043] In the process step (v) of the method of the invention, reaction time and reaction temperature are the parameters that must be taken into consideration for the formation of reaction products. In the method of the present invention, the highest efficiency was achieved by continuing the reaction at about 115 C for 3 hours and vacuuming every 15 minutes after the second hour to remove the water formed with the ester.

[0044] In order to achieve an efficient reaction within the scope of the invention, 65-85% Triisopropanol amine, 15-25% Acetic acid, 1-3% Sulfuric acid by weight are used in the total input composition.

[0045] In a preferred embodiment of the invention, 78% Triisopropanol amine, 20% Acetic acid, 2% Sulfuric acid by weight are used in the total input composition.

[0046] Triisopropanol amine is widely used as GA. TIPA comprises 3 OH groups. Since the carboxyl group contained in acetic acid has a higher polarity than the OH group, modified TIPA is synthesized by replacing the saddle with the OH group in the esterification reaction. Preliminary tests were carried out to ensure suitable conditions for the synthesis to occur, and it was determined that the temperature should be kept around 115 degrees and sulfuric acid should be used as a catalyst.

[0047] TIPA mono acetate, formed as a result of the TIPA esterification reaction, was carried out according to the synthesis scheme shown below. A etate

[0048] In alternative applications, esters with higher polarity can be created by modifying the functional groups of GAs comprising hydroxyl groups with this method.

[0049] Experimental Studies

[0050] Firstly, 2:1 molar ratio of TIPA:acetic acid and 2% of the total mass of sulfuric acid were weighed. First, the water contained in the TIPA solution was separated. Then, the temperature of the TIPA was expected to drop to 50-60 degrees. When the temperature reached the desired level, half of the acetic acid was added to the TIPA and the temperature began to be increased while the mixing process continued with the help of a magnetic fish. Sulfuric acid was added dropwise before the temperature reached 80 degrees. After the reaction continued for a while, the remaining acetic acid was added dropwise. Acetic acid should not be added when the temperature of TIPA is above 80 degrees. Chemicals added to the reactor should be added dropwise. The temperature was fixed at 115 degrees and the reaction was continued for 3 hours. At the end of 2 hours, the water resulting from the ester formed was removed from the environment by vacuuming. The reaction was terminated when no water was seen coming out of the vacuum after 3 hours.

[0051] Analysis Results

[0052] The structures of TIPA and M-TIPA molecules were modeled, and the electron densities of the molecules and the charge values of the electronegative atoms were calculated. By establishing a connection between these calculations and the adsorption power, the grinding aiding powers of the obtained materials were evaluated, and it was aimed to theoretically support the experimental results obtained.

[0053] In this context, the Gaussian 09 program, which has been used extensively by chemists in recent years, was used. The optimizations of the molecules were made in the gas phase environment using the DFT / B3LYP method and the 6-311 ++G(d,p) basis set. Additionally, nbo loads were calculated using the pop=nbo keyword. The optimized structures of the resulting molecules are given in Figure 1 . As can be seen from the figure, the Modified TIPA molecule subject to the invention has a higher electronegativity value.

[0054] Various analyzes were carried out to prove that the synthesized contribution was successfully synthesized. The results and comments of the analyzes are given below.

[0055] Fourier Transform Infrared Spectroscopy (FTIR) Analysis

[0056] The pH value of the synthesized M-TIPA contribution was measured as 5,67 by pH meter. The FTIR analysis result of the synthesized additive is shown in Figure 2.

[0057] The fact that the carbonyl stretching vibration observed around 1700 cm-1in acetic acid and the diffuse OH band observed around 3300 cm'1in the spectrum of the TIPA molecule were observed simultaneously in the FTIR spectrum of the M-TIPA molecule supports the formation of the inventive M-TIPA molecule as a result of the synthesis.

[0058] Gas chromatography mass spectrometry (GC-MS) Analysis

[0059] In order to confirm that the synthesis product was realized, GC-MS spectra of TIPA and M-TIPA molecules were taken. A method suitable for similar molecules has been determined in the literature. The resulting GC-MS chromatogram is given in Figure 3. The red chromatogram given in Figure 3 belongs to the TIPA molecule, and the black chromatogram belongs to the product. When the red chromatogram is scanned in the device library, it is seen that it belongs to TIPA. However, no equivalent of the chromatogram of the product was found in the library. However, when both chromatograms were compared, a new peak was observed at the 18.5th minute. It was determined that in this peak environment, there was a product other than TIPA with a larger molecular weight than TIPA.

[0060] The mass spectrum obtained as a result of analyzing the fragmentation product at minute 18.5 of the chromatogram of the product by mass spectrum is given in Figure 4. When the spectrum obtained was examined, it was determined that the fragmentation products were different from TIPA and an ion with a molecular weight of 233 g / mol was observed. According to these results, it is thought that acetic acid and TIPA reacted in a 1 :1 ratio to form the M-TIPA molecule. In addition, from the chromatogram of the product, it is thought that the reaction efficiency is 60% and the ratio of TIPA and M- TIPA in the product is 40:60. These results support that the modified ester molecule is formed in both 1 :1 and 1 :2 ratios (Table 1).

[0061] Table 1 . Percentages of the products formed and the minutes visible in the GC-MS analysis

[0062] Nuclear Magnetic Resonance Spectroscopy (NMR) Analysis

[0063] Finally,13C-NMR analysis was performed on the product to support that the product obtained as a result of the reaction was M-TIPA. The obtained13C NMR spectrum is shown in Figure 5.

[0064] The13C NMR spectra obtained by theoretical modeling of the13C NMR spectra of the starting materials acetic acid and TIPA molecules and the product M-TIPA molecule are also shown in Figure 6-7. When the spectra of the modeled molecules are examined, it is expected that the carbon peak of acetic acid will be observed only at a value of approximately 176 ppm. However, two carbon peaks at 170 and 172ppm were observed in the experimental spectrum in the figure. These results support that the M- TIPA molecule was obtained. According to the low peak observed at 170 ppm in the spectrum, it is thought that the molecule with a TIPA:acetic acid ratio of 1 :2 is present in the environment.

[0065] Grinding Performance of Modified DEG

[0066] The grinding performance of the modified TIPA according to dosage is given in Table 2. The relative grinding efficiencies of TIPA and Modified TIPA compared to the control cement without GA are shown in Figure 8.

[0067] Table 2. Grinding Performance of Modified TIPA

[0068] Number of Grinding Energy Relative revolutions Time (min) Spent (kWh) Energy Blaine required for for target Efficiency fineness target Blaine (%) value Blaine fineness

[0069] (cm2 / g) fineness

[0070] Control 3780 7350 86.47 36.30

[0071] TIPA-0.025 3750 6720 79.06 33.19 8.57

[0072] TIPA-0.05 3710 6730 79.18 33.24 8.44

[0073] TIPA-0.1 3700 6610 77.76 32.65 10.07

[0074] M-TIPA-0.025 3740 6470 76.12 31.96 11.97

[0075] M-TIPA-0.05 3720 6380 75.06 31.51 13.20

[0076] M-TIPA-0.1 3620 6390 75.18 31.56 13.06

[0077] As can be seen from the table and figure, the modification process applied to the TIPA increased the grinding efficiency by approximately 30% compared to TIPA.

[0078] The presence of both TIPA contribution, mono ester in the product obtained as a result of synthesis can be seen from the analysis results. It has been observed that the chemicals present in the resulting product show an unpredictable synergistic effect, causing an increase in performance. It has been determined that the obtained aid give positive results not only in grinding performance but also in flow and mechanical performances. The flow performance of the resulting product is shown in Table 3.

[0079] Table 3. Flow performances of the additives

[0080] Flow values at a constant

[0081] PCE dosage (cm)

[0082] PCE Requirement for 20 40 60

[0083] 0 min

[0084] Target Flow (%) min min min

[0085] Control 0.12 24.0 19.5 20 16.8

[0086] TIPA-0.025 0.17 22.6 18.2 17.9 15.6

[0087] TIPA-0.05 0.18 23.4 19.4 17.4 15.5

[0088] TIPA-0.1 0.17 22.7 16.3 16.3 14.1

[0089] M-TIPA-0.025 0.13 23.3 19.4 19.3 16.9

[0090] M-TIPA-0.05 0.14 23.2 19.2 19.3 17

[0091] M-TIPA-0.1 0 22.8 18.8 18.4 15.6

[0092] As seen in figure and table, the fact that the modified aid causes less PCE requirement for the target flow value and positively affects the thickening performance is thought to be due to the synergistic effect of the additive ingredients. In Table 4, the 28-day compressive strength of the aid and their relative values compared to the control mixture are given.

[0093] Table 4. 28-day compressive strength values of aid

[0094] Compressive Relative

[0095] Strength Compressive Streng

[0096] (MPa) (%)

[0097] Control 43.15 100

[0098] TIPA-0.025 45.8 106.1

[0099] TIPA-0.05 47.9 111.0

[0100] TIPA-0.1 52 120.5

[0101] M-TIPA-0.025 50.1 116.1

[0102] M-TIPA-0.05 51.05 118.3

[0103] M-TIPA-0.1 48.15 111.6

Claims

CLAIMS1. A new generation grinding aid with high grinding efficiency, strength enhancer, characterized by comprising; Triisopropanol amine monoacetate obtained by esterification reaction of Triisopropanol amine with acetic acid.

2. The grinding aid according to claim 1 , characterized by comprising Triisopropanol amine.

3. The grinding aid according to claim 2, characterized by comprising 40% Triisopropanol amine, 60% Triisopropanol amine monoacetate by weight.

4. A new generation grinding aid synthesis method with high grinding efficiency, strength enhancer, characterized by comprising the following process steps; i. evaporating of its water by heating triisopropanol amine; ii. Lowering the temperature of the heated triisopropanol amine to 50-60 degrees Celsius and adding half of the acetic acid dropwise; iii. Then, heating again and adding catalyst before the temperature reaches 80 degrees Celsius; iv. Adding the remaining acetic acid dropwise; v. Continuing the reaction at approximately 110-120 degrees Celsius and removing the water formed with the ester by applying vacuum repeatedly after the second hour.

5. The method according to claim 4, characterized in that; 65-85% Triizopropanol amine, 15-25% Acetic acid, 1-3% catalyst by weight are used.

6. The method according to claim 4, characterized in that; 78% Triizopropanol amine, 20% Acetic acid, 2% catalyst by weight are used.

7. The method according to claim 4, characterized in that; sulfuric acid is used as catalyst.

8. The method according to claim 4, characterized in that; the reaction is continued at about 115 13.

9. The method according to claim 4, characterized in that; the reaction is continued for 3 hours.

10. The method according to claim 4, characterized in that; the water formed together with the ester is drawn off by vacuuming every 15 minutes after the second hour of the reaction.

Images