DE102010052789A1 - Preparing and purifying polycarbonate (PC) wax from bagasse, useful e.g. in leather industry, comprises dissolving PC wax in e.g. toluene, cleaning with e.g. trichloromethane and acetone and oxidative cleaning with e.g. nitric acid - Google Patents

Abstract

Preparing and purifying polycarbonate (PC) wax from bagasse (pulverized dried mud-cachaza), which is obtained in sugar production from sugar cane, comprises dissolving the PC-wax in e.g. toluene, cleaning with solvents (e.g. trichloromethane), followed by cleaning with acetone or methyl ethyl ketone for resin separation, subsequent oxidative cleaning with 1-35% hydrochloric acid and 1-100% nitric acid at boiling temperature, subsequent washing with water, and subsequent purification with e.g. isopropanol. Preparing and purifying polycarbonate (PC) wax from bagasse (pulverized dried mud-cachaza), which is obtained in sugar production from sugar cane, comprises either dissolving the PC-wax in toluene, heptane or hexane, cleaning with solvents (trichloromethane, dichloromethane, or a petroleum cut-boiling point of 80-110[deg] C, in which the different solubilities of the impurities (soft waxes, fatty components) at different temperatures are used), followed by cleaning with acetone or methyl ethyl ketone for resin separation, subsequent oxidative cleaning with 1-10 times the amount (based on the initial weight of bagasse) of a mixture of 50-80% of a 1-35% hydrochloric acid and 50-20% of 1-100% nitric acid at boiling temperature, subsequent washing with acid-free 1-100 times the amount (based on the initial weight of bagasse) of water, and subsequent purification by 1-100 times the amount (based on the initial weight of bagasse) of isopropanol, ethanol or methanol; or dissolving the PC-wax in toluene, heptane or hexane, cleaning with solvents (trichloromethane, dichloromethane, or a petroleum cut, where the different solubilities the impurities (soft waxes, fatty components) at different temperatures are used), followed by oxidative cleaning with the 1-5 times the amount of a mixture of 50-80% of 10-30% hydrochloric acid and 50-20% of 10-80% nitric acid at the boiling point, followed by washing with acid-free 1-30 times the amount of water, and subsequent purification with the 1-10 times amount of isopropanol, ethanol or methanol.

Description

The invention relates to the work-up of the filter residue in sugar production from sugar cane. From this filter residue, a PC wax is obtained, which can be used after a comprehensive cleaning for technical applications.

State of the art

Already more than 100 years ago, Wynberg patented a technical device in England that made it possible to isolate very pure sugar from the sugarcane plant (publication number GB 190902219 (A) ,

As early as 1915 it was recognized that the sugar cane plant not only sugar, but also other products such. B. waxes can be isolated. On whose refinement (odor refinement) with superheated steam was granted a patent in 1915 (publication number GB 191501332 (A) ,

The sugar (sucrose) only binds slightly more than 30% of the chemical energy stored in the mature sugar cane plant. 35% is contained in the leaves left on the field at harvest, and 35% is contained in the bagasse remaining after squeezing the sugar juice, which is generally re-applied as fertilizer to the sugar cane fields.

From the dried and powdered bagasse (pulverized dried mud - cachaza-), the sugar cane wax can be obtained by eluting with different solvents. There are a variety of publications on the use of different solvents for sugar cane wax extraction and their purification (Recovery of Wax from Dry Mud Press-Cake). For example the book:
The Chemistry and Technology of Waxes by A. Warth 1956 and a variety of patents disclosing various solvents for leaching the sugarcane wax from the bagasse and purifying it have been issued. The most important from the inventor's point of view are the following:

Refining of Sugar Cane Wax: Publication Number CA 513682 (A) ;

Production of Sugar Cane Wax: Publication Number US 2391893 (A) ;

Sugar Cane Wax Refining: Publication Number US 2456641 (A) ;

Bleached Sugar Cane Wax Esters and Amides for Use in Polishes and Production of Esters and Amides: Publication Number GB 773590 (A) ; More recently, only one patent on sugarcane waxes has been known, in which different solvents for the elution of the bagasse are described in countercurrent.

Extracting Waxes from Sugar Cane Residues - using liquid agents in Counterfow and fractional pptn. of Wax fractions from the extract: publication number DE 4037476 (A1) ,

The absence of further publications and patents on this topic suggests that it was not possible to produce a polycosanol wax with sufficient qualities and at competitive prices.

task

The subject of the present invention is therefore the production and purification of a competitive PC wax which can be made available in sufficient quantities.

A particular purpose of the new manufacturing capability is to produce a PC wax that is competitive in quality properties to the synthetic waxes, semi-synthetic waxes and other natural waxes commonly used today, both in quality and in price.

A particularly noteworthy feature of the new PC wax is that the qualities in addition to the applications as a care product for leather and floors also for the additive industry and especially for the car and cosmetics industry, which requires particularly highly purified waxes, is suitable.

A particularly noteworthy feature of the new PC wax is the production of micronizates down to a fineness of 2 microns, which can be produced both by mechanical grinding techniques or air jet grinding, as well as in the spray process from the melt.

solution

It could surprisingly be found a manufacturing process that allows PC wax in a sufficiently good quality, which is also suitable for all technical applications such. B. for the additive, or auto industry or for the cosmetics industry is suitable to produce and produce at competitive prices.

manufacturing

Bagasse (pulverized dried mud - cachaza-) obtained from the production of sugar from sugar cane is treated with aliphatic or cyclic solvents such as (toluene, heptane, hexane) and thus the wax is removed from the bagasse (cachaza).

In addition to PC wax, this wax also contains soft wax components and resins that must be removed. The soft wax-like and fat-like components are dissolved in boiling heat with trichloromethane, dichloromethane, or a petroleum cut boiling between 90-105 ° C; in the cold between 5 and 20 ° C, the soft wax components fall out again and can be removed by filtration. In the solvents, therefore, the soft wax or fat components do not dissolve at low temperatures and can thus be separated by filtration. The different solubilities of the impurities (soft waxes and fats) are exploited at different temperatures. The PC wax obtained contains other resin-like constituents which can be removed with acetone or methyl ethyl ketone at boiling heat.

The pre-cleaned PC wax (crude wax) is then refluxed with a mixture of 5-35% hydrochloric acid and 5-100% nitric acid until the dark substances and impurities contained are oxidatively destroyed. After cooling, the solution is filtered with water, washed free of acid and purified several times with methanol, ethanol or isopropanol, thus removing the last soft wax and fat.

The resulting PC wax already has a very light color - yellowish - and can be lightened as needed with bleach (hydrogen peroxide, sodium peroxide, ozone or chromosulfuric acid).

Examples of production

• 1) 100 grams of an air-dried filter cake in sugar-cane production - bagasse - (pulverized dried mud - chachaza-) is eluted with 500 ml of heptane. After distilling off the solvent, 20 grams of a black very soft wax.

This is then eluted with trichloromethane near the boiling point. The wax and fat components dissolve completely and can be separated after cooling to 5-20 ° C, because the soft wax and fat components are not soluble in the cold. After distilling off the solvent gives about 15 grams of PC wax. The pre-cleaned wax is taken up with acetone at boiling heat. The resinous impurities dissolve and can be separated.

There remain 12 grams of PC wax, which are then boiled with a mixture of 18 grams of 20% hydrochloric acid and 18 grams of 20% nitric acid for one hour at reflux. After filtration, the PC wax is washed with water at room temperature acid-free and washed 3 times with 100 ml of ethanol at room temperature. This gives 7 grams of purified PC wax that can be bleached with a bleach (eg, hydrogen peroxide) as needed.

• – Schmelzpunkt: 74°C;
• – Säurezahl: 107;
• – Verseifungszahl: 153;
• – Esterzahl: 46;
• – Jodzahl: 5

• 2) 100 Gramm eines an der Luft getrockneten Filterkuchens bei der Zuckerherstellung aus Zuckerrohr-Bagasse (pulverised dried mud -Cachaza-) wird mit 500 ml Hexan eluiert. Nach dem Abdestillieren des Lösemittels erhält man 17 Gramm eines schwarzen sehr weichen Wachses.

This PC wax has the following characteristics:

• - melting point: 74 ° C;
• - acid number: 107;
• - Saponification number: 153;
• - Ester number: 46;
• Iodine number: 5

• 2) 100 grams of an air-dried filter cake in sugar-making from powdered dried mud - cachaza- is eluted with 500 ml of hexane. After distilling off the solvent, 17 grams of a black very soft wax.

This is now eluted with dichloromethane just below the boiling point. This dissolves the wax and fat components. After cooling to 5-10 ° C, the cold-insoluble soft wax and fat components precipitate and can thus be separated by filtration. The thus pre-cleaned 13 grams of PC wax are taken up with acetone at boiling heat. In this case, the resinous impurities dissolve and can be separated by filtration.

It leaves 11 grams of PC wax, which are then boiled with a mixture of 16.5 grams of 30% hydrochloric acid and 16.5 grams of 30% nitric acid for one hour at reflux. After filtering, the PC wax is washed acid-free with water at room temperature and washed 3 times with 100 ml of isopropanol at room temperature. This gives 8 grams of purified PC wax, which can be bleached with bleach (sodium peroxide / ozone) as needed.

• – Schmelzpunkt: 76°C;
• – Säurezahl: 100;
• – Verseifungszahl: 130;
• – Esterzahl: 60;
• – Jodzahl: 8

• 3) 100 Gramm eines an der Luft getrockneten Filterkuchens bei der Zuckerherstellung aus Zuckerrohr-Bagasse (pulverised dried mud -Cachaza-) wird mit 500 ml Toluol eluiert. Nach dem Abdestillieren des Lösemittels erhält man 19 Gramm eines schwarzen sehr weichen Wachses.

This PC wax has the following characteristics:

• - melting point: 76 ° C;
• - acid number: 100;
• - Saponification number: 130;
• - Ester number: 60;
• - iodine number: 8

• 3) 100 grams of an air-dried filter cake in sugar-making from powdered dried mud - cachaza- is eluted with 500 ml of toluene. After distilling off the solvent to obtain 19 grams of a black very soft wax.

This is now treated with dichloromethane just below the boiling point. This dissolves all wax and fat components. In the subsequent cooling to 5-10 ° C, the low molecular weight wax and fat components precipitate and can be filtered off. The high-quality PC wax remains in solution and can be obtained after the solvent has been distilled off. The thus pre-cleaned 13 grams of PC wax are taken up with acetone at boiling heat. In this case, the resinous impurities dissolve and can be separated by filtration.

There remain 11 grams of PC wax, which are then briefly boiled with a mixture of 16.5 grams of 33% hydrochloric acid and 16.5 grams of 40% nitric acid at reflux. After filtering, the PC wax is washed acid-free with water at room temperature and washed 3 times with 100 ml of isopropanol at room temperature. This gives 8 grams of purified PC wax, which can be bleached with bleach (sodium peroxide / ozone or hydrogen peroxide) as needed.

• – Schmelpznkt: 79°C;
• – Säurezahl: 100;
• – Verseifungszahl: 130;
• – Esterzahl: 60;
• – Jodzahl: 8

This PC wax has the following characteristics:

• - smelting point: 79 ° C;
• - acid number: 100;
• - Saponification number: 130;
• - Ester number: 60;
• - iodine number: 8

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• GB 190902219 (A) [0002]
• GB 191501332 (A) [0003]
• CA 513682A [0006]
• US 2391893 (A) [0007]
• US Pat. No. 2,456,641 (A) [0008]
• GB 773590 (A) [0009]
• DE 4037476 (A1) [0010]

Cited non-patent literature

• The Chemistry and Technology of Waxes by A. Warth 1956 [0005]

Claims (10)

Process for the preparation and purification of PC wax from powdered dried mud (-Cachaza), as obtained from sugarcane sugar production, after the PC wax has been dissolved out of the bagasse with toluene, heptane or hexane and their cleaning with Solvents (trichloromethane, dichloromethane, or a petroleum cut boiling temperature 80-110 ° C) in which the different solubilities of the impurities (soft waxes, fat constituents) are used at different temperatures and subsequent purification with acetone or methyl ethyl ketone for resin separation and subsequent oxidative purification with the 1 -10 times the amount (based on the weight of the bagasse) of a mixture of 50-80% of a 1-35% hydrochloric acid and 50-20% of a 1-100% nitric acid in the boiling heat and their subsequent acid-free washing with the 1-100 times the amount (based on the weight of the bagasse) of water, as well as their subsequent cleaning with 1-100 times the amount (based on the weight of the bagasse) of isopropanol, ethanol or methanol. Process for the preparation and purification of PC wax from powdered dried mud (-Cachaza), as obtained from sugarcane sugar production, after the PC wax has been dissolved out of the bagasse with toluene, heptane or hexane and their cleaning with Solvents (trichloromethane, dichloromethane, or a petroleum cut) in which the different solubilities of the impurities (soft waxes, fat constituents) are used at different temperatures and subsequent oxidative cleaning with 1-5 times the amount (based on the weight of the bagasse) of a mixture of 50 -80% of a 10-30% hydrochloric acid and 50-20% of a 10-80% nitric acid in the boiling heat and their subsequent acid free washing with 1-30 times the amount (based on the weight of the bagasse) of water, and their subsequent Purification with 1-10 times the amount (based on the weight of the bagasse) of isopropanol, ethanol or methanol. Use of PC wax according to claim one or two for applications in the leather and floor care industry, as well as a lubricant for plastics processing. Use of PC wax according to claim one or two for applications in the office supplies industry as a binder and dispersant for pigments in carbonless papers for the backside coating and as a viscosity regulator of waxy carbon paper pulp for the production of disposable and multi-carbon paper and as building aids for dispersing paraffins with and without Solvents for decoating agents and as an additive to paraffins to improve the heat resistance of candles and in the insulation industry as a release coating for insulating and insulating materials in motor vehicles and in prefabricated buildings and as binders, plasticizers and Abriebverbesserer bitumen modification. Use of PC wax according to claim one or two for applications in the printing ink industry as an improver of scuff and scratch resistance, as well as color yield and to prevent the blocking of prints and to regulate the tack of the ink and for better incorporation of the pigments and in the electrical industry as an additive to insulation and cable encapsulants based on bitumen, petroleum jelly and hydrocarbon waxes and in the film and paper coating as anti-blocking agent in PVCD and polymer coatings for aroma-tight food packaging to regulate the water vapor permeability, for the surface refinement of coated printing, wallpaper and decorative papers, in emulsified form as an additive to coating slips and as a release layer between carrier film and transferring decorative layer in hot stamping foils and in the mold release industry as solvent-borne and aqueous mold release agents for the processing of plastic, rubber, Kera and for the die casting and hot melt coating and hot melt adhesive industry as an additive to hydrocarbon coatings on packaging materials and surface finish for heat sealable, flexible coatings for paper and metal foils and for the woodworking industry as a paraffin emulsifier for the production of chipboard swell protection emulsions and as release agents in the Synthetic resin coating of furniture panels and in the corrosion protection industry as an emulsion or dispersion agent for paraffins and waxes in organic solvents for corrosion inhibitors and as an additive for temporary corrosion protection on vehicles, machinery and equipment. Use of PC wax according to claim one or two for applications in the cosmetics industry as an additive for cosmetic preparations and as a binder for powders in cosmetics and as a thickener for skin creams and pomades and in metal processing as lubricants and in the pharmaceutical industry as a slow-release agent and Brightening agents for dragees and in the manufacture of pigment concentrates by melt technology processable binder for color or additive concentrates and as an additive in the use of plastic-like polyethylenes and polypropylenes as binders to facilitate pigment uptake to achieve higher concentrations and color yields and in the Textile processing industry as an additive for emulsifying systems for paraffin and wax emulsions for the hydrophobization of fabrics and mechanical finishing of sewing threads, silk finish in the embossing calendering and in the Glanzzurichtung and in the citrus fruit industry for surface protection and pore closure as an additive in wax films, which are applied from aqueous emulsions. Use of mixtures of PC wax according to claim one or two, which with one or more waxes or excipients selected from the group consisting of a) PE waxing, b) PTFE waxes, c) PP waxing, d) amide waxes, e) FT paraffins, f) montan waxing, g) natural waxes, h) macro- and microcrystalline paraffins, i) polar polyolefin waxes, j) sorbitan esters, k) polyamides, l) polyolefins, m) PTFE, n) wetting agents, o) silicates for the technical applications according to claim 3-6 can be used. Use according to one or more of claims 3 to 6, wherein the constituent PC wax may be a PC wax modified by oxidation or grafting with maleic anhydride. Use of micronized PC waxes as defined in one or more of claims 3 to 8. Use of PC wax according to claim one or two for applications as an additive for the paint and printing ink industry, comprising wax mixtures according to one or more of claims 3 to 9.