CS274518B1 - Thermooxidizing stabilizer of organic heat carriers - Google Patents

Abstract

The thermooxidation stabiliser of organic heat conductors, mainly hydrocarbonic, contains from 20 to 75 percent of thermally stable, at least one, detergent-dispersant component (Ca, Mg, Ba salts - neutral or alkaline - of oil soluble sulfonic acids originating by sulfonation of aromatic-naphthenic crude-oil oil distillates, mono- and dialkylbenzene sulfonic and alkyl salicylic acids), from 10 to 50 percent by weight of antioxidants (2,6-di-tert.butyl-4-methylphenol, tris-/2,4-(1-phenylethyl)phenyl/phosphite and other), where the eventual rest up to 100 percent is formed by hydrophobic solvent and excipients (anticorrosive agents, deactivators of metals, antifoaming agents, "depressors" and other). As a result of its addition into heat conductors in the amount of 5 to 7 percent the durability of heat conductors will rise at least to quintuple.

Description

BACKGROUND OF THE INVENTION The present invention relates to a thermo-oxidizing stabilizer of organic, in particular hydrocarbon, heat carriers, based on oil-soluble components. at least five times the lifetime extension, even in heat carrier applications at 300 ° C.

It is well known to produce refining additives such as antioxidants, detergents and dispersants, anticorrosive and other additives for lubricants and special oils (Kulijev AM: Khimija i technologija addition to butter and heating. Izdatelstvo Chimija Moskva (1972); Pospisil 3: Antioxidants. Academia. , Prague (1968); Wood GP: 3. Inst. Petrol. 55, 194 (1969); Belgian Pat. 629 945; Stepina V., Vesely V .: Lubricants and Special Oils Veda, Bratislava (1980); Stepina V ., Veselý V .: Lubricants in Tribology, Veda, Bratislava (1985) /, but also brake and hydraulic fluids, but did not pay much attention to stabilization, or the preparation of stabilizers over heat carriers or high temperature heat carriers, whether on hydrocarbon heat carrier bases, dichlorobenzene, diphenyl-diphenyl oxide or polysiloxane mixtures (Golovinskij GP: Chim. promysl. 1975, 311;

US Pat. 3760 020, 3829 518 and 4031 489; Andrianova T.M., Aleksandrov A.A .: Chim. 1974, 178). This was probably due to the fact that heat carriers are usually applied in the absence of air. However, it has long been shown (Macho V. et al .: Czechoslovakian Certificate 201 878) that admixtures of about 0.1 'of antioxidants in hydrocarbon heat carriers, applicable up to a temperature of not more than 270 ° C, increasing the service life, especially retard) increasing viscosity to solidification. However, they did not prevent the formation of deposits and thus clogging the exchanger walls and pipes.

However, the present invention is based on a thermo-oxidizing stabilizer of organic heat carriers, in particular hydrocarbons, which generally contain a solvent and / or a submersible, consisting of 10 to 65% by weight. % of at least one oil-soluble detergent-dispersant component selected from neutral and basic petroleum sulfonates, neutral and basic synthetic alkylarylsulfonates having a carbon number of 8 to 40, an alkaline earth alkyl salicylate having an alkyl number of 10 to 36, and 10 to 40 wt. anti-oxidant or mixtures of oil-soluble antioxidants selected from monoalkylphenols to trialkylphenols with alkyls of 1 to 30, monoarylalkylphenols to triarylalkylphenols of carbon number C | _Q to phosphitated phenols, monoarylphenols, phosphitized arylalkylphenols and their condensates with aliphatic diols to tetraols, nitrogenous antioxidants, optionally with a missing amount of up to 100, forming a hydrophobic solvent and / or excipients.

An advantage of the thermo-oxidizing stabilizer of the present invention is that its addition to the organic heat carriers achieves a complex stabilizing and synergistic effect. It not only prevents oxidation reactions due to soluble or other effects of oxygen present on the oxidation and condensation reactions, prevents the formation of defective heat carrier structures that would lead to its reduced thermal stability, but also thermally initiated polymerization. In addition, it prevents agglomeration of any insoluble resins which may be formed and thus deposits or deposits. clogging of exchanger walls, blockage of pipelines etc. Another advantage is the technical availability of the components, whereby the individual components can be selected from known, usable components and refining additives for lubricants and lubricating oils. the solubility in the underlying organic heat carrier is a temperature stability up to at least 330 ° C. This applies not only to detergent dispersant components and antioxidants of the thermo-oxidizing stabilizer, but also to solvents and excipients. This achieves at least a five-fold increase in the lifetime of the hydrocarbon heat carriers at a temperature of 300 ° C when 6 to 7 wt. thermo-oxidizing stabilizer. As the applied temperature decreases, the service life is not only absolute but also relative.

81

Significant increases in the life of heat carriers, as well as their maximum use, can be increased while maintaining the same organic heat carrier basis directly to i iiii | ia li ι κ lu va 11 í lit jeilnn 11 i trained kumpuneii hunting lermoux i (fasting Láli i i zi tura, but also l.relia then heed good b I. i pupils in the doublers and solubility of components. but also shorter storage at room temperature and especially at low temperatures can cause some components to fall out and, in fact, when pumped into application equipment, the stabilizer content in the heat carrier is reduced and then its service life is reduced. From the standpoint of stabilizer efficiency, sequential dosing is preferable, because at this time an excess amount of the stabilizer is protected from long-term thermal stress, so that initially 2% by weight of the thermo-oxidizing stabilizer can be added to the heat carrier at 1% monthly intervals wt., possibly with the addition of the base heat carrier.

The detergent-dispersant component is neutral or basic sulfonates, such as neutral or weakly basic calcium petrosulfonate, basic calcium petrosulfonate, neutral and basic magnesium petrosulfonate, neutral and basic barium petrosulfonate. Furthermore, synthetic neutral as well as basic calcium or magnesium alkylarylsulfonates, such as calcium monoalkyl to dialkylbenzenesulfonate, with alkyls of 8 to 34. Alkaline earth alkyl salicylates with alkyls of 10 to 36, such as calcium alkyl salicylate, magnesium alkyl salicylate and the like.

Another component is antioxidants. Most preferred include monoalkylphenols to trialkylphenols with C 1 -C 18 alkyl monoarylalkylphenols to triarylalkylphenols having a carbon number of 10 to 40, such as cumylphenol, dicumylphenol, 2,6-dimethyl-4-phenylphenol, and the like. Then, other phenol derivatives and their condensates such as tris / 2,4- (1-phenylethyl) phenyl / phosphite, bis / 2,4- (1-phenylethyl) phenyl / pentaerythritol diphosphite, alkylphenylphosphites, bis (2,4-di-tert-butyl). butylphenyl dipentaerythritol diphosphite, 2,2-bis (4-hydroxyphenyl) propane, followed by temperature-stable nitrogenous antioxidants such as diphenylamine and alkyldiphenylamines, phenyl-1-naphthylamine, phenothiazine, N-alkyl-N'-phenyl-1,4-phenylenediamine with alkyl Cj to C ^ ·

Suitable hydrophobic solvents are, on the one hand, the non-sulfonated proportions of oil fractions of a mixture of petroleum alkanes, cycloalkanes and aromatics or synthetic hydrocarbons, e.g. by oligomerization of alkenes as a rule with subsequent hydrogenation, but also esters of pentaerythritol, distillation residues from the production of cumene and ethylbenzene and the like. It is often part of a conventional hydrocarbon heat carrier.

As the adjuvants to the thermo-oxidizing stabilizers of the present invention, the most important are corrosion and rust inhibitors, metal deactivators and passivators such as sodium benzoate, zinc naphthenate, higher fatty acid amides, ethylenediamine sulfonates, alkylphenolsulfides, benzenapherephenothiophenol, mercaptoxyphenothiothiobenzothiophosphonic acid, and its salts. Then antifoams and exceptionally dyes, pigments, emulsifiers, depressants reducing the structural viscosity of heat carriers, depressants and biocides.

Further data as well as advantages are evident from the examples.

EXAMPLE ·

By formulating a commercial neutral, respectively. weak base, petroleum sulfonate, so-called. calcium petrosulfonate, obtained by neutralizing the oil-soluble sulfoacids, resulting from the sulfonation of aromatic-naphthenic petroleum distillates, with an active substance content of 42.16% by weight, 55.93% by weight; oil and alkalinity respectively. total number

Alkali 14.74 mg KOH / g, together with 2,6-di-tert. butyl-4-methylphenol gives the thermo-oxidative stabilizer of organic heat carriers (No. 1). It consists of 35,1% wt. own petroleum calcium alkylarylsulfonate, i. % detergent dispersant component, 16.7 wt. 2,6-di-tert. % butyl-4-methylphenol as an antioxidant and 48.2 wt. oil boiling in the range of 400 to 500 ° C with the addition of an alkaline component.

To compare the effect of said stabilizer, a commercial hydrocarbon heat exchanger (imported) having a flash point (OK) = 192 ° C is introduced into the heating circuit with a furnace exit temperature of 295 ° C; burning temperature (OK) = 214 ° C; ignition temperature = 350 ° C (temperature class = T 2, hazard class = IV). This heat transfer medium was used for 48 days with a gradual increase in the solids content and formation of deposits so that it had to be weaned after 48 days.

Then the same heat carrier was put on, only 6% by weight was added thereto. said thermo-oxidizing stabilizer no. 1. The heat carrier with said stabilizer was used on an operating scale at an outlet temperature of the furnace for 279 days under otherwise similar conditions and was operable further. It was shut down only due to planned overhaul of the equipment. Thus, it was possible to reliably use said thermo-oxidized stabilized hydrocarbon heat carrier 5.8 times longer than unstabilized.

Example 2

By formulating a commercial neutral, respectively. of a weak base calcium petrosulfonate specified in Example 1 with 2,6-di-tert. butyl-4-methylphenol (antioxidant 4 K) and essentially with tris / 2,4- (1-phenylethyl) phenyl / phosphite (antioxidant 6) yields a thermo-oxidative stabilizer (# 2) of organic heat carriers.

The stabilizer consists of 30.1 wt. calcium alkylarylsulfonate, 14.3 ¾ wt. 2,6-di-tert. % butyl-4-methylphenol, 14.3 wt. predominantly tris / 2,4 (1-phenylethyl) phenyl / phosphite and the remainder up to 100% by weight, m.p. j. 41.3 wt. it consists of a solvent (hydrocarbon oil) with an admixture of an alkali component.

Hydrocarbon heat carrier, consisting of 95% by weight mixtures of dialkyl- and trialkylbenzenes and diphenylalkanes in which the alkyls have 10 to 13 carbon atoms, with admixtures of monoalkylbenzenes and other unidentified admixtures, i. fraction o.t.v. 343-430 ° C, with flash point (OK) = 204 ° C; burning point = 214 ° C; flash point = 365 ° C (temperature class = T 2; hazard class = IV; pour point = -51 ° C) can be used as a heat carrier reliably for up to 40 days without stabilization at 300 ° C. The thermooxidizing stabilizer No. 2 was used in the operating conditions at the outlet temperature of the furnace with occasional refilling of the stabilized heat exchanger with a loss of 247 or more.

Example 3

With the unstabilized commercial hydrocarbon heat carrier alone, as specified in Example 1, a stability test was performed on a laboratory scale and additionally with air at 300-2 ° C (experiment 5). Simultaneously, under completely comparable conditions, the stability test of said hydrocarbon heat carrier with thermooxidizing stabilizer no. 2 (the specification is in Example 2) in an amount of 7 wt. (Experiment C. 6). Then, with the addition of 27% w / w of 6 wt.% Thermo-oxidizing stabilizer no. 3, consisting of 5 wt. % petroleum alkylarylsulfonate of calcium (active component of calcium petrosulfonate), 7 wt. % calcium alkyl salicylate and 1 wt. magnesium alkyl salicylate (with alkyls of 14 to 21), 10 wt. % of arylalkylphenyl phosphites (antioxidant 6), 5 wt. target. % butylated 4-cumylphenol, 1 wt. diphenylpentaerythritol diphosphite and the residue, i. j.

% wt. formed by mineral oil Specified in translation 1. Further, with the addition of 8 wt. thermo-oxidizing stabilizer no. 4 organic heat carriers, consisting of 3 wt. calcium alkylbenzene sulfonate (synthetic alkylarylsulfonate with alkyls of 10 to 14 carbons), 12 wt. % of basic petroleum arylalkylsulfonate (an effective component of commercial calcium petrosulfonate), 5. barium alkylsalicylate, 14% by weight. 2,6-di-tert. % butyl-4-methylphenol, 5 wt. % tris / 2,4- (1'-phenylethyl) phenyl / phosphite, 1 wt. % diphenylamine, 1 wt. % N, N ' -diphenyl-p-phenylenediamine, 0.5 wt. % zinc naphthenate, 0.3 wt. % alkylbenzene phosphonic acid, 0.2 wt. mercaptobenzothiazole and 41 wt. mineral oil.

The results obtained are summarized in Table 1.

Table 1

Sample loading time at temperature Sample without thermo-oxidizing stabilizer - reference Sample with source no. stabilized . 2 Toro sample no. stabilizers 3 Sample with source no, stabili, 4 acid number | mg KOH / g amount of deposits | acid number | mg KOH / g amount of deposits | acid number | mg KOH / g amount of deposits | acid number (mg KOH / g) množstw lumbago 1¾% by weight | 300 [deg.] C | H | 31 0,7B 0.43 0.11 0,004 0.09 0,004 0.09 0,003 50 0.90 10.37 0.22 0,047 0.11 .0,008 0.10 0,005 80 sample stiffened 0.17 0.14 0.14 0,101 0.11 0.09 100 - - 0.24 0.16 0.14 0.11 0.12 0.10 130 - - 0.28 0.18 0.16 0.12 0.13 0.11 150 - - 0.28 0.28 0.19 0.17 0.17 0.13 175 - - 0.30 0.31 0.21 0.19 0.19 0.14 190 - - 0.34 0.42 0.23 0.21 0.19 U-15 210 - - 0.36 0.43 0.24 0.23 0.21 0.17

Example 4

The thermo-oxidative stabilizer of the organic heat carriers is formulated from 40 wt. parts slabobázického petroleum sulfonates, tzv.petrosulfonátu vápsnátéhó.špecifikovanóho in Example l tjl6,864 hmot.částí aktivnsj substance, synthetic 10 hmot.části dialkylbenzénsulfoná are vápsnátóho with alkyl C ₁₃ to C _1Q, 6 hmot.Části Alkyl magnesium alkyl C ₂ About ^_C 28 and 4 wt. parts of barium alkyl salicylate; parts of diphenylamine, 5 wt. alkyldifenylaminu alkyl portion of C _Q-C ^ ₂ »5 wt. Part fanotiazinu, 3 wt. parts of tris (4-nonylfosfitu), 3 ^- hmot.časti 2,2-bis (4'-hydroxyphenyl) propane, N-3 hmot.časti izopropylŇ'- phenyl-4-fehylóndiamínu, 4 wt. part of N-isohexyl-N'-phenyl-1-1,4-phenylandiomine; % phenyl-1-naphthylamine; Parts of benztrlazole and 0.4 wt.%, Parts of 1-hydroxyethanediophosphonic acid and 10 wt. mineral oil. The thermo-oxidizing stabilizer thus formulated in an amount of 7 wt. is added to the hydrocarbon heat carrier, the lifetime of which, by application at 305 + 5 ° C, has increased 6.3 times compared to an un-stabilized heat exchanger.

CS 274518 BI new and 10 wt. parts of mineral oil. The thermo-oxidizing stabilizer thus formulated in an amount of 7 wt. adds to the hydrocarbon heat carrier whose application life at 305-5 ° C increases by 6.3 times compared to the non-stabilized heat carrier.

/

Example 5

The thermo-oxidizing stabilizer of organic heat carriers is formulated from 30 wt. parts of weak base petroleum sulfonate, so-called. calcium petrosulfonate, Specified, i.e. 12.65 wt. parts by weight of active substance, 10 wt. parts of a basic calcium alkylbenzene sulfonate with alkyls of up to 10 wt. parts of magnesium alkyl salcylate and 10 wt. didodecylbenzénsulfonátu parts calcium alkyl C ₂₄ to C _2Q instead immediately subjected · 5 wt. parts by weight of ocryldiphenylamine, 5 wt. parts of 2,6-dimethyl-4-alkyl phenol with alkyl C ₂ to C ^ _Q, 4 wt. parts 2, 6-di-tert. butyl-4-phenylphenol, 2 wt. parts by weight of 2,6-dimethyl-4-phenyl-phenol, 3 parts by weight, parts by weight of N-octyl-N-phenyl-1,4-phenylene diamine; 3 parts by weight of phenyl-O-naphthylamine; parts of dicumylphenol and 1 wt. part of 2,2'-methylene-bis (4-methyl-6-tert-butylphenol), in addition 0.3 part by weight of benztriazole, 0.5 part by weight of 1-hydroxyethanediphosphonic acid, 0.2 part by weight of antifoam (for based on mineral and silicone oil and stearic acid) and 14.0 parts by weight of mineral oil, the thermo-oxidizing stabilizer formulated in this manner is added in an amount of 7% by weight to a hydrocarbon carrier whose application life at 245 ° C is increased compared to non-stabilized heat carrier 7.4 times.

Claims (6)

1. A thermo-oxidative stabilizer of organic heat carriers, in particular hydrocarbons, generally containing a solvent and / or auxiliaries, characterized in that it consists of. 10 to 65 wt. % of at least one oil-soluble detergent-dispersant component selected from between neutral and basic petroleum sulfonates, neutral and basic synthetic alkylarylsulfonates having a carbon number of 8 to 40, an alkaline earth alkyl salicylate with an alkyl number of 10 to 36, and 10 to 40 wt. an antioxidant or a mixture of an oil soluble antioxidant selected from among monoalkylphenols and trialkylphenols with the alkyl of the number of carbons of 1 to 30, monoarylalkylfenolov to triarylalkylfenolov the number of carbons in the possible lekule C _Q1 to ^C 40> fosfitovaných phenols, monoarylfenolov, fosfitovaných arylalkylphenols and condensates of the aliphatic diols to tetrols, % of the nitrogenous antioxidants, whereby the missing amount of up to 100, if any, is a hydrophobic solvent and / or excipients. 2. A thermo-oxidative stabilizer according to claim 1, wherein the neutral and basic petroleum sulfonates are calcium petrosulfonate, basic calcium petrosulfonate, high base calcium petrosulfonate, basic magnesium petrosulfonate, and synthetic neutral and basic alkylarylsulfonates having 8 to 30 carbon atoms. calcium or magnesium alkylarylsulfonates, preferably calcium dialkylbenzenesulfonate, with alkyls having a carbon number of 10 to 14. 3. A thermo-oxidative stabilizer according to claim 1 or 2, wherein the alkaline earth alkyl salicylate is an alkyl salicylate having an alkyl number of 10 to 36, preferably calcium alkyl salicylate. 4. The thermo-oxidative stabilizer according to claims 1 to 3, characterized in that the antioxidant is among monoalkylphenols and trialkylphenols with a number of alkyl carbons from 1 to 30, preferably 2,6-dimethyl-4-alkylfcnol with alkyl C ₂₂ AB and _2U 2 , 6-di-tert. butyl-4-methylphenol and / or monoarylalkylphenols to triarylalkylphenols having a carbon number of 10 to 40, preferably cumylphenol, dicumylphenol, 2, 6-dimethyl-4-phenylphenol and 2,2-methylene-bis- (4-methyl-6- (tert-butyl) phenol. 5. A thermo-oxidative stabilizer according to claim 1, wherein the antioxidant is selected from phosphite phenols and / or phosphite aralkylphenols and their condensates, such as 2,2-bis- (4'-hydroxyphenylpropane), tris- (2,4-di- tert-butylphenyl) phosphite, tris- / 2, 4- (1'-phenylethylphenyl) phosphophosphite, bis (2,4- (1-phenylethyl) / phenyl) pentaerythritol diphosphite, bis (4-cumylphenoidpentaery tri toldiphosphate). 6. A thermo-oxidative stabilizer according to claim 1, wherein the nitrogen component comprises at least one of diphenylamine and an alkylated diphenylamine having an alkyl of up to Γμ, phenyl- to -naphthylamine, phenyl-O-naphthylamine, N, N'-diphenyl- p-phenylenediamine, phenothiazine, N-alkyl-N'-phenyl-1,4-phenylenediamine with C 1 -C ₁₂ alkyl, preferably N-hexyl-N-phenyl-1,4-phenylenediamine.