Process for preparation of tertiary alkyl organic peroxides

Abstract

The present disclosure relates to a process for the preparation of a tertiary alkyl organic peroxide comprising: a) reacting in a first condensation stage a component comprising at least one tertiary alcohol group with a compound comprising at least one tertiary hydroperoxide function in the presence of a catalyst and optionally a co-catalyst, b) separating the aqueous phase from the organic phase in a dehydration stage, and c) separating the aqueous phase from the organic phase in a second condensation stage in the presence of a catalyst and optionally a co-catalyst to form a mixture comprising an organic phase and an aqueous phase, the organic phase comprising a tertiary alkyl organic peroxide. The component containing at least one tertiary alcohol group is further reacted with the compound containing at least one tertiary hydroperoxide group, the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group being at least 3: 1 in the first condensation stage, and the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group being at least 2: 1 in the second condensation stage. And wherein dehydration does not occur during the first condensation stage.

Description

Technical Field

[0001] The present disclosure relates to a method for preparing a tertiary alkyl organic peroxide, which produces a relatively small amount of salt waste in the wastewater stream. Background Art

[0002] Tertiary alkyl organic peroxides are typically produced by the condensation reaction between a tertiary alcohol and a tertiary hydroperoxide. This reaction generates a large amount of water, which needs to be removed during the reaction. Therefore, the reaction is usually carried out in the presence of a large amount of sulfuric acid (H2SO4) and / or water is removed by azeotropic distillation simultaneously.

[0003] Such methods face many technical challenges. A large amount of sulfuric acid is required, which generates a large amount of salt waste in the wastewater, which is not desirable (especially from an environmental perspective). Azeotropic water removal during the reaction process may be dangerous because accidentally removing too much water can lead to a runaway reaction, which is particularly unsafe when peroxides are involved. In addition, the reaction usually needs to be carried out at a lower temperature (e.g., at about 60 °C or lower) to avoid the decomposition of peroxides under such process conditions. The decomposition of peroxides reduces the yield and further causes safety problems. The lower temperature causes the reaction to slow down, thus prolonging the reaction time, which is disadvantageous from an industrial process perspective.

[0004] US5312998 discloses a method for preparing di-tert-butyl peroxide by the condensation reaction of significantly excessive tert-butanol and tert-butyl hydroperoxide in the presence of phosphotungstic acid under high temperature and high pressure. These process conditions are not ideal, especially because phosphotungstic acid has significant safety and environmental hazards, and the tert-alcohol needs to be significantly excessive. When producing tertiary alkyl organic peroxides, the tert-alcohol is usually a more expensive reagent.

[0005] US3308163 discloses a method for preparing an organic peroxide by the condensation reaction between an organic alcohol and an organic hydroperoxide in the presence of an acidic solid ion exchange resin. Azeotropic water removal during the condensation reaction is the key to this method.

[0006] US3919326 discloses a method for preparing an organic peroxide by the condensation reaction between a poly(hydroxyisopropyl)aryl compound containing at least two α-hydroxyisopropyl groups and a chemically equivalent amount of a tertiary alkyl hydroperoxide in the presence of p-toluenesulfonic acid and a large amount of organic solvent. This method requires azeotropic removal of water during the condensation reaction. Even when the process temperature is raised to 70 - 80 °C, the reaction is still relatively slow (> 3.5 hours to complete).

[0007] EP0967194 discloses a method for preparing diisopropylbenzene peroxide by a condensation reaction between cumyl alcohol and cumene hydroperoxide in the presence of an aromatic sulfonic acid. The product yield obtained by the method described in the text is not good (<80%).

[0008] US2016207882 discloses a method for preparing a tertiary alkyl organic peroxide by a condensation reaction between a tertiary organic alcohol and a tertiary organic hydroperoxide in the presence of a sulfonic acid and sulfuric acid, wherein the molar ratio of the sulfonic acid to the tertiary alcohol is between 0.1 and 0.6. The working examples of US2016207882 show that a large amount of sulfuric acid (>60 mol%, relative to the molar amount of the organic alcohol) is required, which can explain why this method requires multiple water washing steps for the final organic layer (presumably to remove a large amount of acidic waste salts) and cannot continuously obtain a good product yield.

[0009] There is still a need for a method for preparing a tertiary alkyl organic peroxide to solve all the above technical problems. Summary of the Invention

[0010] The present inventors have now developed an efficient method for producing a tertiary alkyl organic peroxide to solve all the above technical problems.

[0011] In this regard, a first aspect of the present invention relates to a method for preparing a tertiary alkyl organic peroxide, the method comprising:

[0012] a) In a first condensation stage, in the presence of a catalyst and an optional cocatalyst, reacting a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide functional group to form a mixture comprising an organic phase and an aqueous phase, the organic phase comprising the tertiary alkyl organic peroxide,

[0013] b) In a dehydration stage, separating the aqueous phase from the organic phase, and

[0014] c) In a second condensation stage, in the presence of a catalyst and an optional cocatalyst, continuing to react a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide group,

[0015] wherein, in the first condensation stage, the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group is at least 3:1, and

[0016] wherein no dehydration occurs during the first condensation stage. Detailed Description

[0017] An unexpected finding was that introducing an intermediate dehydration step in the reaction eliminated the need for azeotropic dehydration during the first condensation stage, allowed for increased reaction temperatures (thus shortening the total reaction time), and significantly reduced the total amount of catalyst required (thereby significantly reducing the amount of salt waste generated), all without sacrificing product yield (>90%) and maintaining a very high selectivity for the desired product. However, to reliably obtain these advantages, we found that the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group must be at least 3:1. This ratio is crucial for the success of the process: when the ratio is below 3:1, the resulting suspension is very viscous, making it difficult to stir, and the mixture contains undissolved tertiary alcohol, which leads to fouling of the reactor walls and reduced reaction kinetics, i.e., resulting in an overly long reaction time. We also found that by increasing this molar ratio, the selectivity of the reaction can be improved. Thus, it is preferred that the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group is greater than 3:1, preferably at least 3.5:1, more preferably at least 4:1.

[0018] For the avoidance of doubt, it should be understood that in intermediate dehydration step b), the organic and aqueous phases of step a) are allowed to settle / separate (usually by stopping agitation / stirring), and then the separated aqueous layer is removed.

[0019] Preferably, the component containing at least one tertiary alcohol group and / or the compound containing at least one tertiary hydroperoxide functional group comprises one or more aromatic functional groups such that the tertiary alkyl organic peroxide contains at least one aromatic functional group.

[0020] Preferably, the component containing at least one tertiary alcohol group is selected from α,α'-dihydroxy-1,3-diisopropylbenzene, α,α'-dihydroxy-1,4-diisopropylbenzene or mixtures thereof.

[0021] Preferably, the compound containing at least one tertiary hydroperoxide group is selected from tert-butyl hydroperoxide, tert-amyl hydroperoxide, cumyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumyl isopropyl hydroperoxide, pinane hydroperoxide (2,6,6-trimethylbicyclo[3.1.1]heptyl hydroperoxide), p-menthane hydroperoxide and mixtures thereof. Most preferably tert-butyl hydroperoxide.

[0022] Preferably, the catalyst is an acid catalyst, preferably selected from aliphatic sulfonic acids, aromatic sulfonic acids and / or perchloric acid. Preferred sulfonic acids include, but are not limited to, p-toluenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, benzenesulfonic acid, 1,5-naphthalenedisulfonic acid, ethanesulfonic acid and mixtures thereof. Most preferably p-toluenesulfonic acid (PTSA).

[0023] The method may use a cocatalyst in the first and / or second condensation stage. Preferred cocatalysts include, but are not limited to, water-soluble salts of at least one inorganic acid. Preferred water-soluble inorganic acid salts include, but are not limited to, perchlorates, sulfates, perborates, and mixtures thereof. Preferably, the cation counterion of the inorganic acid salt is an alkali (metal) cation, and the alkali (metal) is preferably sodium, potassium, magnesium, or calcium. More preferred cocatalysts include sodium perchlorate, potassium sulfate, potassium perchlorate, magnesium sulfate, sodium perchlorate, magnesium sulfate, and mixtures thereof. Most preferred is sodium perchlorate.

[0024] Accordingly, in a preferred embodiment, a method for preparing a tertiary alkyl organic peroxide comprises:

[0025] a) In a first condensation stage, reacting α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene, or a mixture thereof with tert-butyl hydroperoxide in the presence of a catalyst (preferably p-toluenesulfonic acid) and an optional cocatalyst (preferably sodium perchlorate) to form a mixture comprising an organic phase and an aqueous phase, wherein the organic phase comprises the tertiary alkyl organic peroxide,

[0026] b) In a dehydration stage, separating the aqueous phase from the organic phase, and

[0027] c) In a second condensation stage, continuing to react α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene, or a mixture thereof with tert-butyl hydroperoxide in the presence of a catalyst (preferably p-toluenesulfonic acid) and an optional cocatalyst (preferably sodium perchlorate),

[0028] wherein, in the first condensation stage, the molar ratio of tert-butyl hydroperoxide to α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene, or a mixture thereof is at least 3:1, and

[0029] wherein no dehydration occurs during the first condensation stage.

[0030] Preferably, a first portion of the catalyst and optionally a cocatalyst are added in the first condensation stage, and a second portion of the catalyst and optionally a cocatalyst are added in the second condensation stage. Preferably, in the first condensation stage, the first portion of the catalyst is added in an amount of 3-15 mol%, preferably 4-10 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group, and in the second condensation stage, the second portion of the catalyst is added in an amount of 3-15 mol%, preferably 4-10 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group. If a cocatalyst is used, preferably, the first portion of the cocatalyst is added in an amount of 2-10 mol%, preferably 3-8 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group and the second portion of the cocatalyst is added in an amount of 2-10 mol%, preferably 3-8 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group in the second condensation stage. It should be understood that the amount of the first portion of the catalyst / optional cocatalyst need not be the same as the amount of the second portion of the catalyst / optional cocatalyst.

[0031] Thus, in another preferred embodiment, a process for preparing a tertiary alkyl organic peroxide comprises:

[0032] a) in a first condensation stage, reacting a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide functional group in the presence of 3-15 mol% catalyst (relative to the initial number of moles of the component containing at least one tertiary alcohol group) and optionally 2-10 mol% cocatalyst (relative to the initial number of moles of the component containing at least one tertiary alcohol group) to form a mixture comprising an organic phase and an aqueous phase, wherein the organic phase comprises the tertiary alkyl organic peroxide,

[0033] b) in a dehydration stage, separating the aqueous phase from the organic phase, and

[0034] c) in a second condensation stage, continuing to react the component containing at least one tertiary alcohol group with the compound containing at least one tertiary hydroperoxide group in the presence of 3-15 mol% catalyst (relative to the initial number of moles of the component containing at least one tertiary alcohol group) and optionally 2-10 mol% cocatalyst (relative to the initial number of moles of the component containing at least one tertiary alcohol group),

[0035] wherein, in the first condensation stage, the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group is at least 3:1, and

[0036] wherein no dehydration occurs in the first condensation stage.

[0037] In an even more preferred embodiment, a process for preparing a tertiary alkyl organic peroxide comprises:

[0038] a) In the first condensation stage, α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof is reacted with tert-butyl hydroperoxide in the presence of 3 - 15 mol% catalyst (preferably p-toluenesulfonic acid; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group) and optionally 2 - 10 mol% cocatalyst (preferably sodium perchlorate; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group) to form a mixture comprising an organic phase and an aqueous phase, wherein the organic phase contains a tertiary alkyl organic peroxide.

[0039] b) In the dehydration stage, the aqueous phase is separated from the organic phase, and

[0040] c) In the second condensation stage, α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof is further reacted with tert-butyl hydroperoxide in the presence of 3 - 15 mol% catalyst (preferably p-toluenesulfonic acid; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group) and optionally 2 - 10 mol% cocatalyst (preferably sodium perchlorate; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group), and the molar ratio of tert-butyl hydroperoxide to α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof is at least 3:1, and

[0041] wherein no dehydration occurs in the first condensation stage.

[0042] As described above, the process conditions allow for a higher reaction temperature. It has been found that the optimal process temperature in the first and / or second condensation stage is 55 to 80 °C, preferably 62 to 80 °C, preferably 65 to 80 °C, preferably 67 to 80 °C and more preferably 69 to 80 °C. The dehydration stage b) can be carried out at a temperature lower than that of the first and / or second condensation stage (e.g., about 50 - 60 °C).

[0043] We have also found that although organic solvents can be used in the methods disclosed herein, they are not a necessary condition for the successful implementation of the methods disclosed herein. Therefore, the reactions in the first and / or second condensation stage can be carried out in the absence of organic solvents. This is beneficial for reducing process costs and improving safety, and significantly improves the environmental impact of the method.

[0044] As described above, the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group must be at least 3:1 (i.e., the hydroperoxide is present in excess). Therefore, in order to improve the overall efficiency of the process, it is preferred that the method further comprises recycling at least a portion of the compound containing at least one tertiary hydroperoxide group present in the product of the second condensation stage to the first condensation stage.

[0045] Accordingly, in another preferred embodiment, a method for preparing a tertiary alkyl organic peroxide comprises:

[0046] a) In a first condensation stage, reacting a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide functional group in the presence of a catalyst and optionally a cocatalyst to form a mixture comprising an organic phase and an aqueous phase, the organic phase comprising the tertiary alkyl organic peroxide,

[0047] b) In a dehydration stage, separating the aqueous phase from the organic phase, and

[0048] c) In a second condensation stage, continuing to react a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide group in the presence of a catalyst,

[0049] wherein, in the first condensation stage, the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group is at least 3:1,

[0050] wherein no dehydration occurs during the first condensation stage, and

[0051] wherein at least a portion of the compound containing at least one tertiary hydroperoxide group present in the product of the second condensation stage is recycled to the first condensation stage.

[0052] In a more preferred embodiment, a method for preparing a tertiary alkyl organic peroxide comprises:

[0053] a) In a first condensation stage, reacting α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof with tert-butyl hydroperoxide in the presence of 3 - 15 mol% catalyst (preferably p-toluenesulfonic acid; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group) and optionally 2 - 10 mol% cocatalyst (preferably sodium perchlorate; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group) to form a mixture comprising an organic phase and an aqueous phase, the organic phase comprising the tertiary alkyl organic peroxide,

[0054] b) In the dehydration stage, separating the aqueous phase from the organic phase, and

[0055] c) In the second condensation stage, α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof is reacted further with tert-butyl hydroperoxide in the presence of 3-15 mol% catalyst (preferably p-toluenesulfonic acid; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group) and optionally 2-10 mol% cocatalyst (preferably sodium perchlorate; mol% relative to the initial number of moles of the component containing at least one tertiary alcohol group), and the molar ratio of tert-butyl hydroperoxide to α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof is at least 3:1,

[0056] wherein no dehydration occurs during the first condensation stage, and

[0057] wherein at least a portion of the tert-butyl hydroperoxide present in the product of the second condensation stage is recycled to the first condensation stage.

[0058] The method disclosed herein can be carried out in a batch process or in a continuous manner.

[0059] It is noted that the various elements of the present invention (including but not limited to the preferred ranges of various parameters) can be combined unless they are mutually exclusive.

[0060] The present invention will be illustrated by the following examples, but the present invention is not limited by these examples.

[0061] Examples

[0062] Example 1 (molar ratio of t-OOH:t-OH = 4.1:1)

[0063] 342.9 g (2.66 mol) of TBHP (as a 70 wt% aqueous solution) was charged into a 1 L glass reactor equipped with a bottom valve, a mechanical stirrer, a thermometer and a reflux condenser. After charging 126.2 g (0.65 mol) of α,α′-dihydroxy-1,3-diisopropylbenzene and 6.63 g (0.032 mol) of 60 wt% aqueous sodium perchlorate solution, the mixture was heated to 62.5 °C. Within 5 minutes, 9.51 g (0.036 mol) of 65 wt% aqueous p-toluenesulfonic acid solution was added to the mixture. After 20 minutes, the temperature dropped to 60 °C. Stirring was stopped and the aqueous phase was removed through the bottom valve.

[0064] Start stirring, add 6.63 g (0.032 mol) of 60 wt% aqueous sodium perchlorate solution, and heat the mixture to 62.5 °C. Within 5 minutes, add 9.51 g (0.036 mol) of 65 wt% aqueous p-toluenesulfonic acid solution to the mixture. After stirring for 100 minutes, cool the mixture to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0065] The addition amount of the catalyst (PTSA) (relative to the initial molar amount of the component containing at least one tertiary alcohol group): 5.5 mol% in the first condensation stage ((0.036 / 0.65) × 100); 5.5 mol% in the second condensation stage; 11 mol% in total.

[0066] The addition amount of the cocatalyst (NaClO4) (relative to the initial molar amount of the component containing at least one tertiary alcohol group): 5 mol% in the first condensation stage ((0.032 / 0.60) × 100); 5 mol% in the second condensation stage; 10 mol% in total.

[0067] GC analysis of the organic phase (excluding TBHP) showed the following composition: 95.53% of α,α′-bis-(tert-butylperoxy)-1,3-diisopropylbenzene, 0.76% of α-(tert-butylperoxy)-α′-hydroxy-1,3-diisopropylbenzene, and 2.53% of α-(tert-butylperoxy)isopropyl-3-isopropenylbenzene.

[0068] Example 2 (molar ratio of t-OOH:t-OH = 4.1:1)

[0069] Charge 171.7 g of TBHP (as a 70 wt% aqueous solution) into a 1 L glass reactor equipped with a bottom valve, a mechanical stirrer, a thermometer, and a reflux condenser. After charging 63.2 g of α,α′-dihydroxy-1,3-diisopropylbenzene and 3.32 g of 60 wt% aqueous sodium perchlorate solution, heat the mixture to 62.5 °C. Within 5 minutes, add 4.76 g of 65 wt% aqueous p-toluenesulfonic acid solution to the mixture. After 20 minutes, the temperature drops to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0070] Start stirring, add 3.32 g of 60 wt% aqueous sodium perchlorate solution, and heat the mixture to 62.5 °C. Within 5 minutes, add 9.52 g of 65 wt% aqueous p-toluenesulfonic acid solution to the mixture. After stirring for 80 minutes, cool the mixture to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0071] The addition amount of the catalyst (PTSA) (relative to the initial molar amount of the component containing at least one tertiary alcohol group): 5 mol% in the first condensation stage; 10 mol% in the second condensation stage; 15 mol% in total.

[0072] The addition amount of the cocatalyst (NaClO4) (relative to the initial molar amount of the component containing at least one tertiary alcohol group): 5 mol% in the first condensation stage; 5 mol% in the second condensation stage; 10 mol% in total.

[0073] GC analysis of the organic phase (excluding TBHP) showed the following composition: 95.91% of α,α′-bis-(tert-butylperoxy)-1,3-diisopropylbenzene, 0.50% of α-(tert-butylperoxy)-α′-hydroxy-1,3-diisopropylbenzene, and 2.51% of α-(tert-butylperoxy)isopropyl-3-isopropenylbenzene.

[0074] Example 3 (molar ratio of t-OOH:t-OH = 4.1:1)

[0075] 172.26 g of TBHP (as a 70 wt% aqueous solution) was charged into a 1 L glass reactor equipped with a bottom valve, a mechanical stirrer, a thermometer, and a reflux condenser. After charging 63.4 g of α,α′-dihydroxy-1,3-diisopropylbenzene and 3.33 g of a 60 wt% aqueous solution of sodium perchlorate, the mixture was heated to 67.5 °C. Within 5 minutes, 4.78 g of a 65 wt% aqueous solution of p-toluenesulfonic acid was added to the mixture. After 20 minutes, the temperature dropped to 60 °C. Stirring was stopped and the aqueous phase was removed through the bottom valve.

[0076] Stirring was started, 3.33 g of a 60 wt% aqueous solution of sodium perchlorate was added, and the mixture was heated to 67.5 °C. Within 5 minutes, 5.73 g of a 65 wt% aqueous solution of p-toluenesulfonic acid was added to the mixture. After stirring for 20 minutes, the mixture was cooled to 60 °C. Stirring was stopped and the aqueous phase was removed through the bottom valve.

[0077] The addition amount of the catalyst (PTSA) (relative to the initial molar amount of the component containing at least one tertiary alcohol group): 6 mol% in the first condensation stage; 7 mol% in the second condensation stage; 13 mol% in total.

[0078] The addition amount of the cocatalyst (NaClO4) (relative to the initial molar amount of the component containing at least one tertiary alcohol group): 5 mol% in the first condensation stage; 5 mol% in the second condensation stage; 10 mol% in total.

[0079] GC analysis of the organic phase (excluding TBHP) showed the following composition: 95.22% of α,α′-bis-(tert-butylperoxy)-1,3-diisopropylbenzene, 0.39% of α-(tert-butylperoxy)-α′-hydroxy-1,3-diisopropylbenzene, and 2.17% of α-(tert-butylperoxy)isopropyl-3-isopropenylbenzene.

[0080] Example 4 (molar ratio of t-OOH:t-OH = 3:1)

[0081] 163.09 g of TBHP (as a 70 wt% aqueous solution) was charged into a 1 L glass reactor equipped with a bottom valve, mechanical stirrer, thermometer, and reflux condenser. After charging 80.0 g of α,α′-dihydroxy-1,3-diisopropylbenzene and 4.21 g of a 60 wt% aqueous solution of sodium perchlorate, the mixture was heated to 67.5 °C. Within 5 minutes, 4.72 g of a 65 wt% aqueous solution of p-toluenesulfonic acid was added to the mixture. After 60 minutes, the temperature dropped to 60 °C. Stirring was stopped and the aqueous phase was removed through the bottom valve.

[0082] Stirring was started, 4.21 g of a 60 wt% aqueous solution of sodium perchlorate was added, and the mixture was heated to 67.5 °C. Within 5 minutes, 4.72 g of a 65 wt% aqueous solution of p-toluenesulfonic acid was added to the mixture. After stirring for 240 minutes, the mixture was cooled to 60 °C. Stirring was stopped and the aqueous phase was removed through the bottom valve.

[0083] The amount of catalyst (PTSA) added (relative to the initial number of moles of the component containing at least one tertiary alcohol group): 4.3 mol% in the first condensation stage; 4.3 mol% in the second condensation stage; 8.6 mol% in total.

[0084] The amount of cocatalyst (NaClO4) added (relative to the initial number of moles of the component containing at least one tertiary alcohol group): 5 mol% in the first condensation stage; 5 mol% in the second condensation stage; 10 mol% in total.

[0085] GC analysis of the organic phase (excluding TBHP) showed the following composition: 92.25% of α,α′-bis-(tert-butylperoxy)-1,3-diisopropylbenzene, 2.17% of α-(tert-butylperoxy)-α′-hydroxy-1,3-diisopropylbenzene, and 4.01% of α-(tert-butylperoxy)isopropyl-3-isopropenylbenzene.

[0086] Example 5 (molar ratio of t-OOH:t-OH = 4.1:1)

[0087] Charge 217.36 g of TBHP (as a 70 wt% aqueous solution) into a 1 L glass reactor equipped with a bottom valve, mechanical stirrer, thermometer, and reflux condenser. After charging 80.0 g of α,α′-dihydroxy-1,3-diisopropylbenzene and 4.20 g of a 60 wt% aqueous solution of sodium perchlorate, heat the mixture to 69.5 °C. Within 5 minutes, add 4.72 g of a 65 wt% aqueous solution of p-toluenesulfonic acid to the mixture. After 20 minutes, the temperature drops to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0088] Start stirring, add 4.20 g of a 60 wt% aqueous solution of sodium perchlorate and heat the mixture to 69.5 °C. Within 5 minutes, add 4.72 g of a 65 wt% aqueous solution of p-toluenesulfonic acid to the mixture. After stirring for 60 minutes, cool the mixture to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0089] The amount of catalyst (PTSA) added (relative to the initial number of moles of the component containing at least one tertiary alcohol group): 4.3 mol% in the first condensation stage; 4.3 mol% in the second condensation stage; 8.6 mol% in total.

[0090] The amount of cocatalyst (NaClO4) added (relative to the initial number of moles of the component containing at least one tertiary alcohol group): 5 mol% in the first condensation stage; 5 mol% in the second condensation stage; 10 mol% in total.

[0091] GC analysis of the organic phase (excluding TBHP) shows the following composition: 94.72% of α,α′-bis-(tert-butylperoxy)-1,3-diisopropylbenzene, 0.83% of α-(tert-butylperoxy)-α′-hydroxy-1,3-diisopropylbenzene, and 3.04% of α-(tert-butylperoxy)isopropyl-3-isopropenylbenzene.

[0092] Example 6 (molar ratio of t-OOH:t-OH = 4.1:1)

[0093] Charge 244.5 g of TBHP (as a 70 wt% aqueous solution) into a 1 L glass reactor equipped with a bottom valve, mechanical stirrer, thermometer, and reflux condenser. After charging 90.0 g of α,α′-dihydroxy-1,3-diisopropylbenzene and 2.70 g of solid sodium perchlorate, heat the mixture to 69.5 °C. Within 5 minutes, add 5.31 g of a 65 wt% aqueous solution of p-toluenesulfonic acid to the mixture. After 20 minutes, the temperature drops to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0094] Start stirring, add 2.70 g of solid sodium perchlorate and heat the mixture to 69.5 °C. Within 5 minutes, add 5.31 g of an aqueous solution of p-toluenesulfonic acid at 65 wt% to the mixture. After stirring for 50 minutes, cool the mixture to 60 °C. Stop stirring and remove the aqueous phase through the bottom valve.

[0095] The amount of catalyst (PTSA) added (relative to the initial number of moles of the component containing at least one tertiary alcohol group): 4.3 mol% for the first condensation stage; 4.3 mol% for the second condensation stage; 8.6 mol% in total.

[0096] The amount of cocatalyst (NaClO4) added (relative to the initial number of moles of the component containing at least one tertiary alcohol group): 5 mol% for the first condensation stage; 5 mol% for the second condensation stage; 10 mol% in total.

[0097] GC analysis of the organic phase (excluding TBHP) showed the following composition: 94.82% of α,α′-bis-(tert-butylperoxy)-1,3-diisopropylbenzene, 1.41% of α-(tert-butylperoxy)-α′-hydroxy-1,3-diisopropylbenzene, and 2.52% of α-(tert-butylperoxy)isopropyl-3-isopropenylbenzene.

[0098] In this specification, unless otherwise clearly stated, the word "or" refers to an operator that returns true when one or both of the stated conditions are met, rather than an "exclusive or" operator, which requires that only one of the conditions be met. The word "comprising" means "including", rather than "consisting of". All prior teachings admitted above are incorporated herein by reference. Any reference to any prior published document herein should not be taken as an admission or indication that its teachings were common general knowledge in Europe or elsewhere as of the date of this document.

Claims

1. A method for preparing a tertiary alkyl organic peroxide, the method comprising: a) In a first condensation stage, in the presence of a catalyst and an optional cocatalyst, reacting a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide functional group to form a mixture comprising an organic phase and an aqueous phase, the organic phase comprising the tertiary alkyl organic peroxide, b) In a dehydration stage, separating the aqueous phase from the organic phase, and c) In a second condensation stage, in the presence of a catalyst and an optional cocatalyst, continuing to react a component containing at least one tertiary alcohol group with a compound containing at least one tertiary hydroperoxide group, wherein, in the first condensation stage, the molar ratio between the compound containing at least one tertiary hydroperoxide functional group and the component containing at least one tertiary alcohol group is at least 3:1, and wherein no dehydration occurs during the first condensation stage.

2. The method according to claim 1, wherein the component and / or the compound comprises one or more aromatic functional groups such that the tertiary alkyl organic peroxide comprises at least one aromatic functional group.

3. The method according to claim 1 or 2, wherein the component containing at least one tertiary alcohol group is selected from α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof.

4. The method according to any one of the preceding claims, wherein the compound containing at least one tertiary hydroperoxide group is selected from tert-butyl hydroperoxide, tert-amyl hydroperoxide, cumyl hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, isopropylcumyl hydroperoxide, pinane hydroperoxide (2,6,6-trimethylbicyclo[3.1.1]heptyl hydroperoxide), p-menthane hydroperoxide or a mixture thereof.

5. The method according to any one of the preceding claims, wherein the reaction in the first and / or second condensation stage is carried out in the absence of an organic solvent.

6. The method according to any one of the preceding claims, wherein the catalyst is an acid catalyst, preferably selected from aliphatic sulfonic acids, aromatic sulfonic acids and / or perchloric acid.

7. The method according to any one of the preceding claims, wherein in the first and / or second condensation stage the catalyst is added in an amount of 3 mol% to 15 mol%, relative to the initial molar amount of the component containing at least one tertiary alcohol group.

8. The method according to claim 7, wherein in the first condensation stage a first portion of the catalyst is added in an amount of 3 mol% to 15 mol%, relative to the initial molar amount of the component containing at least one tertiary alcohol group, and wherein in the second condensation stage a second portion of the catalyst is added in an amount of 3 mol% to 15 mol%, relative to the initial molar amount of the component containing at least one tertiary alcohol group.

9. The method according to any one of the preceding claims, wherein the first and second condensation stages are carried out at a temperature of 55°C to 80°C, preferably 62°C to 80°C, preferably 65°C to 80°C, preferably 67°C to 80°C, more preferably 69°C to 80°C.

10. The method according to any one of the preceding claims, wherein the reaction in the first and / or second condensation stage is carried out in the presence of a cocatalyst.

11. The method according to claim 10, wherein in the first and / or second condensation stage, the cocatalyst is added in an amount of 2 mol% to 10 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group.

12. The method according to claim 11, wherein in the first condensation stage, a first portion of the cocatalyst is added in an amount of 2 mol% to 10 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group, and wherein in the second condensation stage, a second portion of the cocatalyst is added in an amount of 2 mol% to 10 mol%, relative to the initial number of moles of the component containing at least one tertiary alcohol group.

13. The method according to any one of the preceding claims, wherein the catalyst is p-toluenesulfonic acid and the cocatalyst is sodium perchlorate.

14. The method according to any one of the preceding claims, wherein the component containing at least one tertiary alcohol group is selected from α,α′-dihydroxy-1,3-diisopropylbenzene, α,α′-dihydroxy-1,4-diisopropylbenzene or a mixture thereof, and wherein the compound containing at least one tertiary hydroperoxide group is tert-butyl hydroperoxide.

15. The method according to any one of the preceding claims, further comprising recycling at least a portion of the compound containing at least one tertiary hydroperoxide group present in the product of the second condensation stage to the first condensation stage.