Method of preparing preoxyacid solution for delignification and bleaching

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of producing peroxyacids which can be used in delignification and bleaching cellulose materials in the textile industry. The method of preparing a peroxyacid solution for delignification and bleaching involves reaction of acetic acid and hydrogen peroxide in equimolar amounts in the presence of an acid catalyst - sulphuric acid and organophosphonate-nitriletrimethylene phosphonic acid with ozonation, with ozone consumption of 1-4 g/h.

EFFECT: high output of peroxyacid and high efficiency during delignification and bleaching.

1 cl, 2 tbl

 

The invention relates to methods of obtaining peroxyketal, which can be used in technology delignification and bleaching of cellulosic materials, textile industry.

A method of obtaining peroxyacids, namely, that the solution of the acid (formic, acetic), containing the catalyst is sulfuric acid is gradually added while cooling the hydrogen peroxide. However, this method has several disadvantages, the main of which is the low output peroxyketal and their destruction during storage [Weigand-Hilgetag. "Methods of experiment in organic chemistry". M, Chemistry, 1968, s].

Closest to the present invention is a method of obtaining peroxyketal, namely, that the solution of monobasic organic acid, sulfuric acid and organophosphonate (10-100 mg/l) gradually add the hydrogen peroxide solution in equimolar ratios. The disadvantage of this method is not sufficiently high output peroxyacids, lack of efficiency in delignification and bleaching of cellulosic material [Patent RU No. 2200155, IPC SS 407, 2003].

The objective of the invention is to increase the output peroxyacids, the efficiency of delignification and bleaching.

The problem is solved in that the process of obtaining peroxyacids lead by the interaction of uksosn the th acid and hydrogen peroxide in equimolar quantities in the presence of acid catalyst and organophosphonate, when this process is carried out during ozonation at a flow rate of ozone 1-4 g/hour.

Upon receipt of peroxyacids is used acetic acid according to GOST 61-65, sulphuric acid GOST 4204-77, hydrogen peroxide GOST 177-88, as organophosphonate - nitriltrimetilenfosfonovaya acid (NTF) - TU 6-02-1171-79.

The claimed method is illustrated by the following examples. The results on the application of peroxyketal shown in table 1. The determination peroxyacids and hydrogen peroxide in solution was carried out according to the following procedure: from the resulting solution peroxyoctanoic acid (book) pipette select 1 ml, dilute to 100 ml in a volumetric flask. From the resulting solution by pipette select the 10 ml titration flask, add 1 ml of 2 N sulfuric acid (H2SO430 ml of distilled water and titrate with 0.1 N potassium permanganate solution KMPO4to weak pink color (V1). After that add 1 spatula of dry potassium iodide KJ, 5 ml of 0.5%starch solution and titrate with 0.1 N sodium thiosulfate solution Na2SiO3until complete discoloration (V2).

The hydrogen peroxide concentration is calculated by the formula:

where V1- the volume of potassium permanganate, followed by titration of the sample, ml;

N1- normality of potassium permanganate (0,1 N);

te1- milliequivalent peroxide is odorata (0.017 mg/mol);

VCR- volume of sample taken for titration (1 ml);

ρ is the density N2About2, g/cm

Concentration peroxyoctanoic acid is calculated by the formula:

where V2- the volume of sodium thiosulfate solution, followed by titration of the sample, ml;

N2the normality of sodium thiosulfate (0,1 N);

te2- milliequivalent peracetic acid (0.038 mg/mol);

VCR- volume of sample taken for titration (1 ml);

ρ is the density of book, g/see

[Aviolanda, Wpisalem. "Practical work on chemistry of wood and cellulose". M: Forestry, 1965, s].

Example 1 - prototype

In a reactor equipped with a jacket for cooling load of 62.5 g of 96% acetic acid (1 mol), of 3.65 g of 96% sulfuric acid and 100 mg/l NTF and, gradually, in the course of one hour while cooling to 20°C is poured 113,3 g of 30% solution of hydrogen peroxide (1 mol). The resulting solution after prilipanie of hydrogen peroxide was incubated for 1 hour.

Example 2 according to the invention

In a reactor equipped with a jacket for cooling, mixing device load of 62.5 g of 96% acetic acid (1 mol), of 3.65 g of 96% sulfuric acid and 100 mg/l NTF and gradually cooling to 20°C is poured 113,3 g of 30% solution of hydrogen peroxide (1 mol)while passing through a solution of ozone at the rate of 1 g/hour. The solution obtained by the Le prilipanie of hydrogen peroxide was incubated for 1 hour.

Example 3 according to the invention

The process of obtaining, the boot order is the same as in examples 1, 2. Changed the amount of ozone to 2 g/hour.

Example 4 according to the invention

The process of obtaining, the boot order is the same as in examples 1, 2. Changed the amount of ozone - 4 g/hour.

Example 5 according to the invention

The process of obtaining, the boot order is the same as in examples 1, 2. Organophosphonate - NTF - 10 mg/l the Amount of ozone - 4 g/hour.

Example 6 according to the invention

The process of obtaining, the boot order is the same as in examples 1, 2. Organophosphonate - NTF - 50 mg/l the Amount of ozone - 4 g/hour.

Example 7 control

The process of obtaining, the boot order is the same as in examples 1, 2. Changed the amount of ozone - 5 g/hour.

From the data presented in table 1, shows that the use of ozone in the number of 1-4 g/HR when receiving peracetic acid and increase output 5-26,7%, the content of hydrogen peroxide in the solution of 21.9-52,4%. The increase in consumption of ozone over 4 grams/hour (example No. 7) does not increase output either peracetic acid or hydrogen peroxide. In our opinion, the increase in the yield of peracetic acid and the content of hydrogen peroxide due to the oxidizing properties of ozone, shifting the equilibrium towards the formation of reaction products.

The delignification and bleaching of sulfite pulp spent with trains, receiving the tion in examples 1-7 at a concentration of mass 10%, pH 5, the exposure time of 60 min, 70°C and the flow rate remains constant composition (in terms of peroxyoctanoic acid) - 3% of the mass of absolutely dry pulp. The determination of the degree of delignification (Kappa number), the white were performed by standard techniques [GOST 10070-64, GOST 7690-76]. The data presented in table 2.

From the data presented in table 2 shows that peroxyacids, obtained by the ozonization of the inventive method have a higher delignification and bleaching properties. In our opinion, this is due to the significantly higher content in the solution, along with peroxyketal, hydrogen peroxide and, accordingly, the change of the ratio between delignification agents - peroxyoctanoic acid and hydrogen peroxide. In example 1 (prototype), this ratio is almost 2:1, as in examples 2-6 - 1,77÷1,65.

The claimed method allows to obtain peroxyacids with increased output and high efficiency for delignification and bleaching of sulfite pulp.

Table 1
Effect of ozone on the yield of peroxyketal
The way to obtainContent peroxyacidsThe content of hydrogen peroxide
Example 1 (the prototype)28,014,1
Example 2 (invention)30,517,2
Example 3 (invention)33,019,4
Example 4 (invention)35,5a 21.5
Example 5 (invention)35,6a 21.5
Example 6 (invention)35,3a 21.5
Example 7 (control)35,5a 21.5

Table 2.
The influence of peroxyacids rates of delignification and bleaching of sulfite pulp
The way to obtainThe Kappa numberWhite, %
Example 1 (the prototype)9,573,0
Example 2 (invention)8,7 75,5.
Example 3 (invention)7,477,8
Example 4 (invention)7,080,1
Example 5 (invention)7,080,1
Example 6 (invention)7,180,0
Example 7 (control)7,180,0

A method of obtaining a solution peroxyketal for delignification and bleaching by reacting acetic acid and hydrogen peroxide in equimolar quantities in the presence of acid catalyst is sulfuric acid and organophosphonate-nitriltrimetilenfosfonovaya acid, wherein the process is conducted at the ozonation at a flow rate of ozone 1-4 g/H.



 

Same patents:

FIELD: chemical technology.

SUBSTANCE: invention relates to a method for synthesis of peroxyformic acid and its salts. Method involves electrolysis of 0.5-2.0 M formic acid solution or its alkaline metal salts in diaphragm electrolyzer on dioxide-lead anode at current density values 0.05-0.5 A/cm2 in the presence of ammonium thiocyanate taken in the concentration 1.0-1.5 g/l. Method provides exclusion using strong dangerously explosive oxidizing agents, high selective of the synthesis process, possibility for continuous realizing the process and preparing the end substance of high purity.

EFFECT: improved method of synthesis.

4 tbl, 4 ex

The invention relates to a process for producing organic peroxide compounds specifically peroxyoctanoic acid

FIELD: chemistry.

SUBSTANCE: invention relates to synthesis of hydroperoxides of alkylaromatic hydrocarbons which can serve as a source of oxygen-containing organic compounds (phenol, methylphenols, acetone, cyclohexanone etc) and as an initiator of emulsion polymerisation of unsaturated hydrocarbons. The invention discloses a method for synthesis of hydroperoxides of alkylaromatic hydrocarbons through liquid-phase oxidation of these hydrocarbons with atmospheric oxygen at atmospheric pressure, process temperature of 110-130°C, for 1-3 hours in the presence of a 4-methyl-N-hydroxyphthalimide catalyst in amount of 1.0-2.0 wt %.

EFFECT: catalyst prevents use of an initiator and alkaline additives, which considerably simplifies the process, higher conversion of initial alkylaromatic hydrocarbons while preserving high selectivity of the process.

2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing isopropyl benzene hydroperoxide (IPB HP) which is then used to produce phenol and acetone using what is known as industrial cumol method. According to the invention, isopropyl benzene hydroperoxide is obtained by oxidising isopropyl benzene with molecular oxygen. The catalyst used is iron nanopowder with specific surface area of 6.9 m2/g, obtained through electrical explosion of a conductor in a nitrogen atomsphere. The process is carried out at 50-60°C.

EFFECT: increased output of isopropyl benzene hydroperoxide.

1 cl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to petrochemical industry and can be used in combined production of styrene and propylene oxide. Ethylbenzene hydroperoxide is obtained in accordance with the invention by oxidising ethylbenzene with atmospheric oxygen in a continuous reactor at atmospheric pressure in the presence of N-hydroxyphthalimide as a catalyst in amount of 0.5-3 wt % and temperature of the process of 125-130°C until achieving content of ethylbenzene hydroperoxide of 19.2%.

EFFECT: increased conversion of ethylbenzene and selectivity of the process.

1 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of continuous oxidation of saturated cyclic hydrocarbons using oxygen, into a mixture of hydroperoxide, alcohol and ketones. The method involves feeding into the lower part of a column and in parallel flow, a stream of oxidisable liquid hydrocarbon and a gas stream containing oxygen, and degassing the liquid phase in the upper part of the column by forming a gas dome and extraction of the degassed liquid phase. The gas containing oxygen is let into different compartments of the column, and into the dome and/or liquid phase at the level of the degassing zone, or directly above. A stream of non-oxidising gas with output sufficient for maintaining concentration of oxygen in the gas layer at the level of volume concentration, less than or equal to the upper limiting concentration of oxygen is supplied.

EFFECT: possibility of implementing a method with high selectivity on an explosion safe level.

9 cl, 1 dwg, 1 ex

FIELD: chemistry.

SUBSTANCE: invention concerns method of isopropylbenzene hydroperoxide (IPBHP) concentration, applied in phenol and acetone production by isopropylbenzene method. The claimed method involves feed of oxidate for rectification into a vessel with gas phase separation in top part or into condensers of rectification columns.

EFFECT: reduced load on columns, enhanced column efficiency, reduced loss of IPBHP with distillate, power saving.

3 cl, 2 dwg, 3 tbl, 3 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to method for synthesis of alkylaryl peroxide-containing compound. Method involves the following steps: (a) oxidation of alkylaryl compound to yield the alkylaryl hydroperoxide-containing reaction substance; (b) treatment of at least part of the reaction substance containing alkylaryl hydroperoxide synthesized at the step (a) wherein this the reaction product comprises less 0.05% of sodium (by mass); (c) separation of product synthesized at the step (b) for hydrocarbon phase containing alkylaryl hydroperoxide and an aqueous phase; (d) repeating steps (b) and (c) by one or some time being optionally. Also, synthesis of alkylaryl hydroxide involves the additional treatment step (e) of at least part of hydrocarbon phase containing alkylaryl hydroperoxide synthesized at steps (c) or (d), olefin and a catalyst to yield alkylaryl hydroxide and oxirane compounds, and (f) separation of at least part of oxirane compound from alkylaryl hydroxide. Synthesis of alkenylaryl involves the additional step (g) of dehydration of at least part of alkylaryl hydroxide synthesized at step (f). Invention provides simplifying the technological process resulting to synthesis of improved substance containing alkylaryl hydroperoxide from which alkylaryl hydroxide is prepared followed by preparing alkenylaryl.

EFFECT: improved method of synthesis.

11 cl, 1 tbl, 6 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to production of alkylaryl hydroperoxides useful as starting material in production of propylene oxide and alkenylaryl. Process of invention comprises following stages: oxidation of alkylaryl compound to form reaction product containing alkylaryl hydroperoxide; contacting at least part of reaction product with basic aqueous solution; separation of hydrocarbon phase containing alkylaryl hydroperoxide from aqueous phase; containing at least part of above hydrocarbon phase with aqueous solution containing waste water, said aqueous solution containing less than 0.2% alkali metal and/or salt (determined as ratio of metal component to total amount of solution); and separation of hydrocarbon phase from aqueous phase. By bringing at least part of above hydrocarbon phase containing alkylaryl hydroperoxide into interaction with propylene and catalyst, alkylaryl hydroxide and propylene oxide are obtained. At least part of propylene oxide is then separated from alkylaryl hydroxide. Dehydration of at least part of alkylaryl hydroxide results in formation of alkenylaryl.

EFFECT: reduced amount of contaminating by-products in alkylaryl hydroperoxide preparation stage.

8 cl, 4 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention proposes a method for synthesis of organic hydroperoxide comprising the reduced amount of impurities. Method involves the following steps: (a) oxidation of organic compound to yield the reaction product comprising organic hydroperoxide; (b) contacting at least part of the reaction product comprising organic hydroperoxide with the basic aqueous solution; (c) separation of hydrocarbon phase containing organic hydroperoxide from an aqueous phase; (d) washing out at least part of the separated hydrocarbon phase containing organic hydroperoxide, and (e) contacting at least part of hydrocarbon phase containing organic hydroperoxide with a protective layer comprising a solid adsorbent wherein a solid adsorbent shows porosity 50-98% by volume. Except for, invention proposes a method for preparing oxirane compound from hydrocarbon phase obtained at the step (e) by the method described above and containing alkylaryl hydroperoxide. The presence of the protective layer reduces the pressure increment in the catalyst layer that is caused by the declined content of impurities in the raw comprising alkylaryl hydroperoxide.

EFFECT: improved preparing method.

7 cl, 2 ex

The invention relates to organic chemistry, namely the synthesis of the perforated deciphered specifically PERFLUORO-2-methyl-3-oxohexanoate used as an initiator radical copolymerization of fluorinated olefins

The invention relates to an improved method of decomposition of the hydroperoxide with the formation of a mixture containing the corresponding alcohol and ketone, comprising the stage of: a) adding water in the amount of 0.5-20% in the mixture containing the hydroperoxide; (b) the deletion of specified volume of water in such a way that together with water removes water-soluble impurities; C) removing the remaining water in such a way that the reaction mixture is not more than 2% of water; and (d) decomposition of the specified hydroperoxide by contacting the reaction mixture with a catalytic amount of a heterogeneous catalyst containing gold, supported on a carrier

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention proposes a method for synthesis of organic hydroperoxide comprising the reduced amount of impurities. Method involves the following steps: (a) oxidation of organic compound to yield the reaction product comprising organic hydroperoxide; (b) contacting at least part of the reaction product comprising organic hydroperoxide with the basic aqueous solution; (c) separation of hydrocarbon phase containing organic hydroperoxide from an aqueous phase; (d) washing out at least part of the separated hydrocarbon phase containing organic hydroperoxide, and (e) contacting at least part of hydrocarbon phase containing organic hydroperoxide with a protective layer comprising a solid adsorbent wherein a solid adsorbent shows porosity 50-98% by volume. Except for, invention proposes a method for preparing oxirane compound from hydrocarbon phase obtained at the step (e) by the method described above and containing alkylaryl hydroperoxide. The presence of the protective layer reduces the pressure increment in the catalyst layer that is caused by the declined content of impurities in the raw comprising alkylaryl hydroperoxide.

EFFECT: improved preparing method.

7 cl, 2 ex

FIELD: industrial organic synthesis.

SUBSTANCE: invention relates to production of alkylaryl hydroperoxides useful as starting material in production of propylene oxide and alkenylaryl. Process of invention comprises following stages: oxidation of alkylaryl compound to form reaction product containing alkylaryl hydroperoxide; contacting at least part of reaction product with basic aqueous solution; separation of hydrocarbon phase containing alkylaryl hydroperoxide from aqueous phase; containing at least part of above hydrocarbon phase with aqueous solution containing waste water, said aqueous solution containing less than 0.2% alkali metal and/or salt (determined as ratio of metal component to total amount of solution); and separation of hydrocarbon phase from aqueous phase. By bringing at least part of above hydrocarbon phase containing alkylaryl hydroperoxide into interaction with propylene and catalyst, alkylaryl hydroxide and propylene oxide are obtained. At least part of propylene oxide is then separated from alkylaryl hydroxide. Dehydration of at least part of alkylaryl hydroxide results in formation of alkenylaryl.

EFFECT: reduced amount of contaminating by-products in alkylaryl hydroperoxide preparation stage.

8 cl, 4 ex

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to method for synthesis of alkylaryl peroxide-containing compound. Method involves the following steps: (a) oxidation of alkylaryl compound to yield the alkylaryl hydroperoxide-containing reaction substance; (b) treatment of at least part of the reaction substance containing alkylaryl hydroperoxide synthesized at the step (a) wherein this the reaction product comprises less 0.05% of sodium (by mass); (c) separation of product synthesized at the step (b) for hydrocarbon phase containing alkylaryl hydroperoxide and an aqueous phase; (d) repeating steps (b) and (c) by one or some time being optionally. Also, synthesis of alkylaryl hydroxide involves the additional treatment step (e) of at least part of hydrocarbon phase containing alkylaryl hydroperoxide synthesized at steps (c) or (d), olefin and a catalyst to yield alkylaryl hydroxide and oxirane compounds, and (f) separation of at least part of oxirane compound from alkylaryl hydroxide. Synthesis of alkenylaryl involves the additional step (g) of dehydration of at least part of alkylaryl hydroxide synthesized at step (f). Invention provides simplifying the technological process resulting to synthesis of improved substance containing alkylaryl hydroperoxide from which alkylaryl hydroxide is prepared followed by preparing alkenylaryl.

EFFECT: improved method of synthesis.

11 cl, 1 tbl, 6 ex

FIELD: chemistry.

SUBSTANCE: invention concerns method of isopropylbenzene hydroperoxide (IPBHP) concentration, applied in phenol and acetone production by isopropylbenzene method. The claimed method involves feed of oxidate for rectification into a vessel with gas phase separation in top part or into condensers of rectification columns.

EFFECT: reduced load on columns, enhanced column efficiency, reduced loss of IPBHP with distillate, power saving.

3 cl, 2 dwg, 3 tbl, 3 ex

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of continuous oxidation of saturated cyclic hydrocarbons using oxygen, into a mixture of hydroperoxide, alcohol and ketones. The method involves feeding into the lower part of a column and in parallel flow, a stream of oxidisable liquid hydrocarbon and a gas stream containing oxygen, and degassing the liquid phase in the upper part of the column by forming a gas dome and extraction of the degassed liquid phase. The gas containing oxygen is let into different compartments of the column, and into the dome and/or liquid phase at the level of the degassing zone, or directly above. A stream of non-oxidising gas with output sufficient for maintaining concentration of oxygen in the gas layer at the level of volume concentration, less than or equal to the upper limiting concentration of oxygen is supplied.

EFFECT: possibility of implementing a method with high selectivity on an explosion safe level.

9 cl, 1 dwg, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to petrochemical industry and can be used in combined production of styrene and propylene oxide. Ethylbenzene hydroperoxide is obtained in accordance with the invention by oxidising ethylbenzene with atmospheric oxygen in a continuous reactor at atmospheric pressure in the presence of N-hydroxyphthalimide as a catalyst in amount of 0.5-3 wt % and temperature of the process of 125-130°C until achieving content of ethylbenzene hydroperoxide of 19.2%.

EFFECT: increased conversion of ethylbenzene and selectivity of the process.

1 cl, 1 ex

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing isopropyl benzene hydroperoxide (IPB HP) which is then used to produce phenol and acetone using what is known as industrial cumol method. According to the invention, isopropyl benzene hydroperoxide is obtained by oxidising isopropyl benzene with molecular oxygen. The catalyst used is iron nanopowder with specific surface area of 6.9 m2/g, obtained through electrical explosion of a conductor in a nitrogen atomsphere. The process is carried out at 50-60°C.

EFFECT: increased output of isopropyl benzene hydroperoxide.

1 cl, 3 ex

FIELD: chemistry.

SUBSTANCE: invention relates to synthesis of hydroperoxides of alkylaromatic hydrocarbons which can serve as a source of oxygen-containing organic compounds (phenol, methylphenols, acetone, cyclohexanone etc) and as an initiator of emulsion polymerisation of unsaturated hydrocarbons. The invention discloses a method for synthesis of hydroperoxides of alkylaromatic hydrocarbons through liquid-phase oxidation of these hydrocarbons with atmospheric oxygen at atmospheric pressure, process temperature of 110-130°C, for 1-3 hours in the presence of a 4-methyl-N-hydroxyphthalimide catalyst in amount of 1.0-2.0 wt %.

EFFECT: catalyst prevents use of an initiator and alkaline additives, which considerably simplifies the process, higher conversion of initial alkylaromatic hydrocarbons while preserving high selectivity of the process.

2 tbl, 2 ex

FIELD: chemistry.

SUBSTANCE: invention relates to the technology of producing peroxyacids which can be used in delignification and bleaching cellulose materials in the textile industry. The method of preparing a peroxyacid solution for delignification and bleaching involves reaction of acetic acid and hydrogen peroxide in equimolar amounts in the presence of an acid catalyst - sulphuric acid and organophosphonate-nitriletrimethylene phosphonic acid with ozonation, with ozone consumption of 1-4 g/h.

EFFECT: high output of peroxyacid and high efficiency during delignification and bleaching.

1 cl, 2 tbl

Up!