Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D251/00—Heterocyclic compounds containing 1,3,5-triazine rings
  • C07D251/02—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings
  • C07D251/12—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members
  • C07D251/26—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members with only hetero atoms directly attached to ring carbon atoms
  • C07D251/30—Only oxygen atoms
  • C07D251/36—Only oxygen atoms having halogen atoms directly attached to ring nitrogen atoms

Definitions

• the present invention relates to an improved process for manufacturing chloro-s-triazine triones which are sometimes referred to as chloro- cyanuric acids or chloroisocyanuric acids. More specifically, this invention pertains to a method for preparing chloro-s-triazine triones, particularly trichloro-s-triazine trione, having enhanced crystal properties.
• chloro-s-triazine triones such as trichloro-s-triazine trione or dichloro-s-triazine trione is well known in the prior art.
• chloro-s-triazine trione crystals having increased size can be produced by adding to the reaction mixture from which these crystals are formed, from 50 to 1,000 ppm of a chlorinated hydrocarbon containing 1 to 6 carbon atoms and having not more than one hydrogen atom in its molecule.
• the crystal size of chloro-s-triazine triones may be increased by adding, as a surface active agent, an alkali metal alkyl sulfate or an alkali metal alkylarylsulfonate to the reaction mixture while maintaining a pH between about 1.0 and 4.5.
• U.S. Patent No. 3,941,784 teaches the crystal promotion of chloro-s-triazine trione by adding to the reaction mixture a small amount of polyoxyethylene, polyoxypropylene, or polyoxyethylene- polyoxypropylene copolymers.
• chloro-s-triazine triones in particular dichloro-s-triazine trione, trichloro-s-triazine trione and mixtures thereof, having enhanced crystal properties and exhibiting outstanding stability when formulated with other chemicals in bleaching products, are obtained by the use of certain crystal modifiers during the manufacture of chloro-s-triazine triones.
• These crystal modifiers are alkylated diphenyloxide disulfonic acids wherein the alkyl group contains from 8 to 14 carbon atoms, or their alkali metal salts. In these compounds, the sulfonic groups are attached to carbon atoms of the diphenyloxide nucleus.
• the crystal modifier is added to the reaction mixture in the form of the alkali metal disulfonate rather than in the acid form.
• the preferred alkali metal is sodium.
• crystal modifiers used in this invention achieve superior bleach stability in the product are not fully understood. However, as indicated above, one of the factors involved is believed to be the crystalline form of the product and the mechanism is therefore regarded as one of crystal modification and the additive is referred to herein as a "crystal modifier".
• crystal modifiers which can be used in the process of the invention are sodium octyl diphenyloxide disulfonate; sodium nonyl diphenyloxide disulfonate; sodium n-decyl diphenyloxide disulfonate; potassium n-decyl diphenyloxide disulfonate; sodium dodecyl diphenyloxide disulfonate; octyl diphenyloxide disulfonic acid; dodecyl diphenyloxide disulfonic acid; sodium tridecyl diphenyloxide disulfonate; and potassium tetradecyl diphenyloxide disulfonate.
• a preferred crystal modifier for use herein is sodium dodecyl diphenyloxide disulfonate.
• This disulfonate is commercially available. It can be obtained in liquid form as a 45-50% by weight concentrate, for example, from Dow Chemical Company under the trade name «Dowfax 2A1 ErasmusThe preferred concentration of the crystal modifier used in the process of the present invention is 20 to 500 parts per million (ppm) by weight based on the reactor contents. Improvements can be achieved with these crystal modifiers at higher or lower concentrations, however. Most preferred are concentrations of from 100 to 300 ppm by weight based on the reactor contents.
• a preferred procedure for the production of trichloro-s-triazine trione by the process of the invention comprises mixing a slurry of substantially pure cyanuric acid with alkali metal hydroxide (e.g., sodium or potassium hydroxide, preferably the former), to prepare an aqueous solution in which the alkali metal hydroxide to cyanuric acid molar ratio is about 3:1.
• the solution is then fed continuously to a reactor to which chlorine and the crystal modifier are also fed continuously, while maintaining the temperature of the reactor contents at about 25°C with a pH of about 3.5.
• the pH can vary between about 1.0 and 4.5, the range of 3.0 to 4.5 is preferable.
• the crystal modifier feed rate is adjusted to maintain the desired concentration of the crystal modifier in the reactor.
• the product (trichloro-s-triazine trione) is withdrawn from the reaction as a slurry, then filtered, dried and packaged.
• the particles of trichloro-s-triazine trione are single, clear crystals of suitable size and structural integrity to exhibit outstanding bleach stability when formulated with other chemicals in bleaching and scouring compositions.
• the reactor may contain initially a small volume of water having at least a portion of the crystal modifier charge in solution.
• dichloro-s-triazine trione is the desired end product instead of trichloro-s-triazine trione.
• the former can be prepared in a manner similar to that described above except that the feed solution can be prepared by mixing a cyanuric acid slurry with an alkali metal hydroxide to produce a solution having a hydroxide to cyanuric acid mole ratio of about 2.1:1.
• Chlorine is typically introduced at a rate sufficient to maintain a pH in the range 2.1 to 2.3.
• control of the drying conditions as for the drying of conventionally-produced chloro-s-triazine triones should be exercised.
• trichloro-s-triazine trione should not be dried at temperatures which will cause the particle temperature to exceed about 130°C.
• Example 3 The invention is illustrated by Example 3 of the following Examples.
• Examples 1 and 2 are comparative Examples. Parts and percentages are by weight unless otherwise specified.
• This Example illustrates a conventional preparation of trichloro-s-triazine trione wherein no crystal modifier or promoter is employed.
• a feed solution was prepared by mixing a cyanuric acid slurry with sodium hydroxide to produce a solution containing 7.6% cyanuric acid with a mole ratio of sodium hydroxide to cyanuric acid of 3.2:1.
• the chlorination reaction was provided for by a jacketed 1.4 litre glass reactor equipped with a stirrer, side arm for product overflow, subsurface feed tube and a fritted glass sparger. Starting with water in the reactor, feed solution was introduced through the feed tube at about 40 ml per minute and chlorine was introduced through the sparger at about 5.5 grams per minute.
• the pH was controlled in the range 3.5 to 3.8 by adjusting the chlorine feed rate, and the reaction temperature was controlled between 22° and 27°C by circulating ice water through the reactor jacket.
• the product slurry which overflowed the side arm, was filtered to separate the crystalline product from the mother liquor, giving a filter cake containing 10 to 12% by weight free moisture, and was then dried in an oven at about 100°C. (The product was observed to settle slowly from the slurry.)
• Example 2 was conducted in a manner identical to that of Example 1 except for the presence of a crystal promoter within the scope of aforementioned US. Patent No. 3,941,784.
• the promoter employed was a polyoxyethylene-polyoxypropylene copolymer identified as «Pluronic L-62» and available from BASF-Wyandotte Corporation. ( «Pluronic» is a Registered Trade Mark at least in the United Kingdom.)
• a feed solution identical to that of Example 1 was prepared.
• a chlorination was conducted as described in Example 1 except that 200 ppm (based upon the reactor contents) of polyoxyethylene-polyoxypropylene copolymer was introduced to the reaction mixture. Part of this 200 ppm promoter addition was admitted to the initial reactor water charge and part was admitted to the feed solution. The resulting product in this case was observed to settle rapidly and was filtered to 4-5% free moisture.
• Example 3 illustrates the preparation of trichloro-s-triazine trione with the aid of a crystal modifier in accordance with the present invention.
• Example 3 was conducted in a manner identical to that of Example 1 except for the addition of 200ppm, based upon the reactor contents, of sodium dodecyl-diphenyloxide disulfonate (as a 45% concentrate in a liquid vehicle) to the reaction vessel.
• the resulting trichloro-s-triazine trione product exhibited outstanding clarity in the single clear crystals which were produced.
• Dichloro-s-triazine trione can be prepared by a procedure similar to that of Example 3 using a feed solution prepared by mixing a cyanuric acid slurry with sodium hydroxide to produce a solution containing about 9.8% of cyanuric acid and having a sodium hydroxide to cyanuric acid mole ratio of about 2.1:1, and introducing chlorine at about 7.1 grams per minute to maintain a pH in the range 2.1 to about 2.3.
• trichloro-s-triazine trione was prepared by a procedure similar to that of Example 3, but using 200 ppm of a sodium (C t4 alkyl)benzene sulfonate, an example of the alkali metal alkylarylsulfonates disclosed in U.S. Patent 3,453,274, instead of sodium dodecyl diphenyloxide disulfonate.
• Example 1 The unmodified, unpromoted product of Example 1 exhibited the smallest apparent particle size.
• the product of Example 2 although exhibiting an apparent size greater than that of Example 3 in screen measurements, is suspected of undergoing size attrition during certain conditions of handling in compounding operations sometimes employed to formulate cleansing and bleaching compositions referred to hereafter.
• apparent particle size is not the sole factor determining stability.
• Bleach stability of cleansing compositions containing chloro-s-triazine triones is customarily determined by measuring the percentage of available chlorine remaining in the cleansing composition following a predetermined number of days exposure of the composition to ambient conditions.
• One such aging test calls for the placement of the cleansing composition in half- filled canisters and exposing the canisters to air at 80OF (26.7°C) and 80% relative humidity with both open and closed tops on the canisters.
• Chlorine stability results with the product of Example 1 were substandard and unacceptable for commercial cleansing compositions.
• the following Table compares the chlorine stability of the products of Example 2 and Example 3. It will be seen that the single clear crystal of the product of Example 3, although of smaller apparent particle size than that of Example 2 according to screen measurements, is nonetheless a superior product from the standpoint of chlorine stability.
• the data in the Table were obtained following the typical aging test described above, using open top canisters, using typical cleansing formulations containing 80-85 percent of an abrasive and 0.5-1 percent of the trichloro-s-triazine trione, the balance being an alkaline builder. From these results, it can be seen that the use of sodium dodecyl diphenyloxide disulfonate according to the process of the invention contributes significantly to available chlorine stability of the product.

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• Detergent Compositions (AREA)
• Plural Heterocyclic Compounds (AREA)

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• 1977
  • 1977-07-05 US US05/812,556 patent/US4087608A/en not_active Expired - Lifetime
• 1978
  • 1978-07-03 EP EP78300115A patent/EP0000292B1/en not_active Expired
  • 1978-07-03 DE DE7878300115T patent/DE2860575D1/de not_active Expired
  • 1978-07-04 JP JP8182178A patent/JPS5414990A/ja active Granted
  • 1978-07-04 AU AU37746/78A patent/AU516181B2/en not_active Expired
  • 1978-07-04 CA CA306,725A patent/CA1084926A/en not_active Expired
  • 1978-07-04 IT IT25311/78A patent/IT1096963B/it active

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