Method of producing mineral tanning agent. RU patent 2509810.

FIELD: chemistry.

SUBSTANCE: sulphate titanyl-containing and aluminium-containing salts and ammonium sulphate are mixed. The sulphate titanyl-containing salt used is crystalline titanyl sulphate and the sulphate aluminium-containing salt used is aluminium-ammonium alum or aluminium sulphate. The components are mixed in weight ratio of TiO₂:Al₂O₃:(NH₄)₂SO₄=1:0.02-0.1:1.7-2.5 and then reacted in solid-phase mechanical activation mode while supplying energy at a rate of 2-5 kW-h/kg of the mixture for 15-50 minutes to form a tanning agent. Before reacting the components, water can be added to the mixture in an amount of not more than 3.5 wt % with respect to the weight of the mixture. The disclosed method is characterised by a 5.5 times shorter duration on average and enables to reduce consumption of ammonium sulphate 1.75-2.25 times while avoiding use of sulphuric acid. The obtained composite tanning agent with content of the active titanium component of 17.6-22.7 wt % with respect to TiO₂ has basicity of 40-43.6%.

EFFECT: method is technologically effective and environmentally friendly.

3 cl, 8 ex

The invention relates to the chemical technology of obtaining of such products used as mineral tanning agent in the production of leather and fur.

Upon receipt of mineral tanning agent composition widespread method of liquid-phase, based on a joint deposition components of the solution. The implementation of this method requires considerable consumption of reagents, high enough duration of the process and is accompanied by formation of environmentally harmful effluents. With this in mind the significant interest represents the solid-phase method, which consists in mechanical mixing ingredients with tanning properties.

A method of obtaining mineral tanning agent (see A.S. 859455 SSSR, MKI 3 C14C 3/04, 1981), according to which produces a mixture of sulfate aluminum, selftolerance sodium and sulfocationite ammonium when the ratio of components in terms of the oxides: Al 2 O 3 :(ZrO 2 +TiO 2 )=0,5-2:1 and ZrO 2 :TiO 2 =0,5-2:1, dissolution, mixture for 20 minutes in the water, at a temperature of 25-30 C and adding at hashing in 2 admission an interval of 10 minutes of sodium bicarbonate solution for alkalizing the resulting solution to pH 3.0 and 3.3.

The disadvantages of this method include the fact that for a mix of original components with tanning properties, cannot provide them with the necessary interaction and obtain composite mineral tanning agent. Additional procedures are required mixing in hot water and add sodium bicarbonate solution for alkalizing received tanning solution. All this reduces the technological method of obtaining mineral tanning agent. In addition, the source tanning components are expensive products.

Also known taken as a prototype method for production of mineral tanning agent (see A.S. 1227678 SSSR, MKI 4 C14C 3/00, 3/04, 1986), namely, that the titanyl sulphate and ammonium dissolve in water with the receipt of such sulfate solution, which is injected sulphuric acid and ammonium sulfate to the beginning of the formation of crystals double salts of titanyl sulphate ammonium, and then within 1-5 hours add simultaneously aluminium sulphate to molar relationship aluminum to titanium 0,03-0,2:1, sulfur acid and ammonium sulphate to their total content in the free state 400-600 g/L. thus receive mineral tanning agent, comprising, mass%: 16,5-18,2 TiO 2 , 0,58-2,2 Al 2 O 3 . Total consumption of sulfuric acid and ammonium sulfate is 0,8-1,2 kg per 1 kg of tanning agent.

To the disadvantages of this method include the fact that it is a long time and with only a single operation of adding aluminum sulphate, sulphuric acid and ammonium sulfate is 1-5 hours, and with a large consumption of sulfuric acid and ammonium sulfate, which remain in the filtrate forming liquid effluents. Recycling wastewater complex and costly, and draining their negative impact on the environment. All this reduces the technological way. Get a tanning agent that has low basicity that requires adjustment of the solution before tanning.

The present invention is directed to achievement of the technical result consists in increasing the maintainability of the way, by reducing its duration, reduce reagent consumption and improve environmental performance while providing a high properties of tanning agent.

The technical result is achieved by a method for production of mineral tanning agent that includes the mixture of sulfate titanosoderzhashchie and aluminium salts and ammonium sulfate and interaction of components of mixture formation of tanning agent, according to the invention, as sulfate titanosoderzhashchie salt use crystal the titanyl sulphate, mix components mass ratio in per TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:(0,02-0,1):(1,7-2,5), and their interaction is carried out in a mode of solid-phase mechanical activation supplying energy 2-5 kWh/kg of mixture for 15-50 minutes.

To achieve the technical result is promoted also by the fact that as aluminium sulphate salts take alimohammadi alum or aluminum sulfate.

To achieve the technical result is also that prior to interaction of components in the mixture, add water in the quantity not more than 3.5% in relation to the mass of the mixture.

The essential features of the claimed invention that define the scope of legal protection and sufficient for the above technical result, serve and correlate with the results as follows.

Use as sulfate titanosoderzhashchie salt crystal of titanyl sulphate without ammonium ion is because the mixing and interaction of components of a tanning agent in solid-phase mode does not require the presence of ammonium sulfate in the free state so that you can enter the components in the amount close to the stoichiometry without excessive consumption, and provides by mechanical activation obtaining composite mineral tanning material with predetermined composition and properties. Used sulfate titanil can be anhydrous TiOSO 4 , and also in the form monohydrate TiOSO 4 ·H 2 O or dihydrate TiOSO 4 ·2H 2 o

The components are mixed mineral tanning material mass ratio in per TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:(0,02-0,1):(1,7-2,5) provides the content of components in the mixture, close to stoichiometric, which allows to obtain mineral tanning agent with almost 100% the output of the target product and high tanning properties. When the content Al 2 O 3 and (NH 4 ) 2 SO 4 in the mix, respectively, less than 0.02 and 1.7 towards TiO 2 not provided the required value of basicity of a tanning agent that reduces the content of leather tanning components in titanium and aluminium. When the content Al 2 O 3 and (NH 4 )SO 4 in the mix, respectively more than 0.1 and 2.5 in relation to the TiO 2 is reduced for a list of mineral tanning agent for the account of the excessive presence in it of sulfuric acid, which affects the efficiency of interaction tanning components with skin collagen.

Realization of interaction of components in the solid-phase mode of mechanical activation allows in one stage, without the use of a solvent to increase the chemical activity component, which facilitates their cooperation, and contributes with a low consumption of reagents and short time to obtain mineral tanning material with high tanning properties.

The holding of interaction between the components supplying energy 2-5 kWh/kg of mixture for 15-50 minutes allows to reduce the duration of the process and the consumption of reagents and thus increase its manufacturability while providing high properties of tanning agent. When supply of energy less than 2 kWh/kg of the mixture within less than 15 minutes is not reached the necessary level of the active surface of the particles of components and reduced content of tanning agent in mechanically activated the product. Energy supply in quantity more than 5 kWh/kg of mixture for over 50 minutes is technologically unjustified because the energy saturation of the surface of activated particles.

The combination of the above features is necessary and sufficient to obtain a technical result of the invention, a reduction of the length of the way, reducing the reagent consumption and improve environmental performance while providing a high properties of tanning agent that increases the adaptability of the way.

In some cases, of the preferred embodiment of the invention, the following specific operations and operational parameters.

Use alimohammadi alum or aluminum sulphate as aluminium sulphate salts due to the fact that aluminium sulphate ion of these compounds with forms titanium is resistant to hydrolysis of the complex, which is essential for efficient filling leather tanning components due to the acceleration of diffusion processes.

Add to the mixture before its mechanical activation of water in the quantity not more than 3.5%, it is desirable to improve physical-chemical processes of mechanical activation. Water performs the function of surface-active substances, which allows to reduce energy costs for mechanical activation. Introduction of water in quantities of more than 3.5% it is undesirable due beyond stoichiometric content of the mixture components, which has a negative effect on the properties of the tanning agent. In addition, excess water is not possible to get a tanning agent at one stage.

The above private features of the invention allows method in optimal from the point of view of reducing its duration, reduce reagent consumption and improve environmental performance while providing a high properties of tanning agent.

The essence of the proposed method can be explained by the following Examples.

Example 1. Make a mixture 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 ·2H2O, 200 g alimohammadi alum (NH 4 )Al(SO 4 ) 2 ·12H 2 O (20 g Al 2 O 3 ) and 1700 ammonium sulphate (NH 4 ) 2 SO 4 (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,02:1,7). The mixture is placed in a planetary mill and subjected solid mechanical activation supplying energy 2 kWh/kg of mixture for 50 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 4400 g tanning material that contains, mass%: 22,7 TiO 2 , 0,45 Al 2 O 3 . Basicity of tanning agent, defined as the ratio of active sulfuric acid to acid, associated with titanium and aluminium, is equal to 43;6%.

Example 2. Make a mixture 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 ·H 2 O, 400 g alimohammadi alum (40 g Al 2 O 3 ) and 2000 ammonium sulfate (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,04:2). The mixture is placed in a planetary mill and subjected solid mechanical activation supplying energy 3 kWh/kg of mixture for 30 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 4900 g tanning material that contains, mass%: 20,4 TiO 2 , 0,82 Al 2 O 3 and has basicity of 41.7%.

Example 3. Make a mixture 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 , 400 g alimohammadi alum (40 g Al 2 O 3 ) and 2500 g of ammonium sulfate (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,1:2,5). The mixture is placed in a planetary mill and subjected solid mechanical activation supplying energy 5 kWh/kg of mixture for 50 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 5400 g tanning material that contains, mass%: 18,6 TiO 2 , 0,75 Al 2 O 3 and has basicity of 40.8%.

Example 4. Produce mixing 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 ·H 2 O, 680 g of aluminum sulfate Al 2 (SO 4 ) 3 ·18H 2 O (100 g Al 2 O 3 ) and 2500 g of ammonium sulfate (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,1:2,5). The mixture is placed in a planetary mill and subjected solid mechanical activation supplying energy 5 kWh/kg within 15 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 5680 g tanning material that contains, mass%: 17,6 TiO 2 , 1,76 Al 2 O 3 and has basicity 40,0%.

Example 5. Make a mixture 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 ·H 2 O, 340 g of aluminum sulfate (50 g Al 2 O 3 ) and 2200 grams of ammonium sulfate (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,05:2,2). The mixture is placed in a planetary mill and subjected solid mechanical activation supplying energy 3 kWh/kg of mixture for 30 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 5040 g tanning material that contains, mass%: 20,2 TiO 2 , 1,0 Al 2 O 3 and has basicity 42,1%.

Example 6. Make a mixture 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 , 400 g alimohammadi alum (40 g Al 2 O 3 ) and 2000 ammonium sulfate (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,04:2). The mixture is placed in a planetary mill add 0,17 l of water (3.5% in relation to the mass of the mixture) and subjected solid mechanical activation supplying energy to 3.6 kWh/kg of the mixture within 20 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 5070 g tanning material that contains, mass%: 19,7 TiO 2 , 0,79 Al 2 O 3 and has basicity of 41.8%.

Example 7. Make a mixture 2500 g (1000 g according TiO 2 ) of such salts in the form of crystalline titanyl sulphate TiOSO 4 , 400 g alimohammadi alum (40 g Al 2 O 3 ) and 2000 ammonium sulfate (mass proportions of the components in the calculation of TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:0,04:2). The mixture is placed in a planetary mill add 0,12 litres of water (2.5 wt.% in relation to the mass of the mixture) and subjected solid mechanical activation supplying energy to 4.0 kWh/kg of the mixture within 25 minutes. In the process of lowering the size of components and increasing surface activity of the particles is their interaction with the formation of the composition of mineral tanning agent. Get 5020 g tanning material that contains, mass%: 19,9 TiO 2 , 0,80 Al 2 O 3 and has basicity of 41.7%.

Example 8 (the prototype). Take 400 g monohydrate titanyl sulphate and ammonium (NH 4 ) 2 TiO(SO 4 ) 2 ·H 2 o to Dissolve it in water and get 1 liter of solution containing 80 g/l TiO 2 . In the obtained solution is injected ammonium sulfate (NH 4 ) 2 SO 4 and sulfuric acid until the beginning of crystallization double salts of titanyl sulphate and the ammonium, then in parallel within 1 hour add 21 ml solution of aluminium sulphate, containing 500 g/l Al 2 (SO 4 ) 3 ·18H 2 O, ammonium sulfate and sulfuric acid. Salting out to carry the total content of free sulfuric acid and ammonium sulfate 400 g/l and molar relationship aluminum to titanium 0,03. Get 450 g mineral tanning material that contains, mass%: 18,2 TiO 2 , 0,8 Al 2 O 3 and has basicity 39,1%.

Thus, from the above Examples 1-8 follows that the proposed method for mineral tanning material in comparison with the prototype is characterized on average, 5.5 times less duration and reducing consumption of sulfate of ammonium 1.75-2.25 times as the use of sulphuric acid. Obtained composite tanning material with titanium content of the active component 17,6-22,7% by weight in terms of TiO 2 has basicity 40-43,6%. The method according to the invention is more environmentally friendly and technologically. It is relatively simple and can be implemented using the equipment available.

1. Method for production of mineral tanning agent that includes the mixture of sulfate titanosoderzhashchie and aluminium salts and ammonium sulfate and interaction of components of mixture formation of tanning agent, characterized in that as sulfate titanosoderzhashchie salt use crystalline titanyl sulphate, mix components mass ratio in per TiO 2 :Al 2 O 3 :(NH 4 ) 2 SO 4 =1:(0,02-0,1):(1,7-2,5), and their interaction is carried out in a mode of solid-phase mechanical activation supplying energy 2-5 kWh/kg of mixture for 15-50 minutes.