Table 2

Extraction Data and Characte7ictics of Mired Acids free from Non-saponz$ible Matter

Name of Oil Unsap. Iodinevalue* Sap. equivalent* Protein the variety content matter observed calculated observed calculated content

010 010 "In

5-23 1 5-232 KHSB 1 KHSBP UPSM-19 JS-2 Jupitor 2 120 UGM-20 Improved pellicans Hardee Monetta

20.6 0.1 18.8 0.2 15.6 0.5 20.8 0.1 19.3 0.3 22.4 0.2 17.7 0.1 21.2 0.2 25.8 0.1 18.2 0.2

18.7 0.1 23.2 0.7

134.5 132.8 133.2 145.0 136.5 140.9 137.0 134.7 130.3 129.0

135.0 143.1

135.0 133.4 133.9 145.3 137.7 141.1 137.7 135.1 130.7 128.7

134.3 143.5

278.8 277.0 278.4 278.8 278.5 280.0 279.5 279.0 278.9 279.8

278.8 280.0

279.6 276.5 279.0 279.1 279.8 279.7 279.8 279.6 279.2 280.1

279.1 280.7

38.8 39.9 38.8 37.9 39.4 37.5 38.8 40.0 36.9 36.4

36.3 38.1

* These values are measured on mixed acids free from non-saponifiable matter and arecal- culated from the composition determined in this investigation

Table 3 L i t e r a t u r e

FatD/ Acid Composition (Wt. 96)

Nameof 149* 169 189 209 229 18:l 182 18:3 the variety 5-23 1 0.1 7.8 3.5 1.8 1.2 255 57.1 3.1 5-232 0.2 7.2 2.9 1.8 0.5 28.7 55.4 3.3 KHSB 1 0.1 8.6 4.1 1.0 0.9 28.2 51.2 6.0 KHSB-2 - 7.3 2.3 0.6 0.9 25.9 54.1 9.0 UPSM- 1 - 6.7 2.5 1.1 1.3 29.7 52.6 5.8 JS-2 - 8.0 3.2 1.8 1.7 21.7 56.5 7.1 Jupitor - 7.6 3.6 2.0 1.5 25.5 52.9 7.0 2120 - 8.0 3.7 2.2 1.5 26.6 51.3 6.8 UGM-20 0.8 8.3 4.0 2.0 1.5 28.6 48.4 6.5 1.pellicans 0.4 9.0 4.4 1.2 1.5 28.4 50.7 4.2 Hardee - 9.1 4.9 1.0 1.3 26.6 49.2 8.0 Monetta - 3.5 2.3 1.6 1.2 30.6 54.8 6.0 * These figures indicate the number of carbon atoms and the num- ber of double bonds present in the fatty acid

' R. C. Badami and K . B . Patil, Minor Seed Oils X: Physico-chemi- cal characteristics and fatty acid com sition of seven minor oils, J. Oil Technol. Assoc., India VII, 82 b 7 5 ] . A. R. S. Kartha and R. Narayan, The glyceride structure of natural fats I: A technique of quantitative determination of glyceride types in natural fats, Indian J. Agri. Sci. 27,73 [ 19571. R. C. Badami,Reversedphasepartitioncolumnchromatography: A review, Chem. and Ind. [London] 1965,12 11. Annual Report of The All India coordinated Research Project on Soybean, Bangalore and Dharwad Centres, (1980-8l),Univer- sity of Agricultural Sciences, Bangalore, (private communica- tion).

A c k n o w l e d g e m e n t Oil-Seed Section, University of Agricultural Sciences, Dharwad;

the C.S.I.R. foraSenior Research Fellowship to Jayshree %zkkar,and Mr. Shanthwerbhadraya for providing the parental characteristics of the varieties investigated. Received lSth March 1982.

Separation and Analysis of Wax from Egyptian Sugar Cane Filter Press Cake

Waxes from filter press cake of the by-product of the Sugar Cane Industry gained from various Egyptian Cane Sugar Factories were studied. A method for continuous extraction of wax filter cake using different solvent i. e. toluene, naphthqacetone, fractionated gasoline,denatured and refined alco- hol was investigated. The speed and ease of extraction using different sol- vents were compared. By using toluene as solvent the highest percentage of crude wax was obtained from Edfu, which gave 14.55 %, while extraction with refined alcohol produced 12.65 010 crude wax from QIS. Decolorization of crude wax was carried out by sodium hypochlorite, nitric acid, chlorine, sulphur dioxide and acetone. The pure wax was separated from the fatty oil fraction by fractional crystallization from 7 8 to Oo C. The greater portion of wax can be obtained at 300 C. Hard, brittle wax was obtained between 45' to 200 C. The crude and refined waxes had properties comparable to camauba waxandothercommercialwaxes.TheEgyptiancanesugarwaxescanbeuti- lized in paper, ink, coating, varnishes, pharmaceuticals, cosmetics and ferti- lizer industries.

* Author's address: Dr.-Ing. A. M. Auam, National Research Centre, Chemical Technology and Sugar Industry Unit, El Do&, Cairo, Egypt.

lkennung und Analyse von Wachs aus FiltexpreBkuchen dea iigypti- schen Zuckerrohra Es wurden die RlterpreSkuchen von Nebenprodukten derzuckerrohrin-

dustrie untersucht, die von verschiedenen igyptischen Zuckerrohrfabriken erhalten wurden. Weiterhin wurde die kontinuierliche Extraktion der Wachsfilterkuchen mit verschiedenen Losungsmitteln wie Toluol, Naphtha, Aceton, Benzinfraktionen und denaturisiertem und raffiniertem Alkohol untersucht. Geschwindigkeit und Leichtigkeit der Extraktion bei Verwen- dung verschiedener Lasungsmittel wurden verglichen.Bei Verwendung von Toluol a l s Losungsmittel wurde mit 14.55 O/o der hiichste Gehalt an rohem Wachs aus Edfu erhalten, wiihrend die Extraktion von @IS mit raffiniertem Alkohol 12.65 'Yo Wachs ergab. Das rohe Wachs wurde durch Natrium- hypochlorit, Salpetersaure, Chlor, Schwefeldioxid und Aceton entfirbt. Durch fraktionierte Kristallisation zwischen 7 8 und 00 C wurde das reine WachsvonderFetto1fraktiongetrennt.Bei 300CkanneingriiSererWachsan- teil erhaltenwerden.Zwi~chen45~und28 Cwurdehartes,briichigesWachs erhalten. Die rohen und raffinierten Wachse hatten Eigenschaften, die mit denen von Camauba-Wachs und anderen kommerziellen Wachsen ver- gleichbar sind. Die tigyptischen Zuckerrohrwachse konnen in der industriel- len Produktion von PapiqTinte, ijberziigen, Lacken, Pharmazeutika, Kos- metika und Diingemitteln verwendet werden.

I n t r o d u c t i o n In 1840 Awquzn3 in New Orleans isolated and described

cuticle wax recovered from the deposit found on the surface

FETTE SEIFEN . ANSTRICHMITTEL 86.Jahrgang Nr 6 1984 247

of sugar cane. Various methods have been suggested from the recovery of cuticle wax, but the first commercial recovery was by solvent extraction of crude wax from cake in Natal South Africa" during World War I.

During World War I1 interest in sugar cane wax revived, and commercial installations were built in Cuba and the United States for the solvent extraction and retining of cane

Solvents that effectively remove the wax from the clarifi- cation muds also remove oily and resinous materials. The sol- vents usually employed in the extraction of crude cane wax are low-boiling hydrocarbons, alcohols or acetones. When the extraction is carried out on wet muds a water-insoluble solvent is preferred.

Several solvents were used in the extraction of sugar cane wax. Swenson" recommended the extraction with acetone. Raoand Gupta" used ethanol and petroleum ether. McLoud" and Broegand Bakh5 used isopropyl alcohol for fractionation of the wax. Goep@rtH obtained crystalline wax by chdliig from 15 to 20'C. Thls wax was previously extracted by refluxing with isopropyl acetone for 1 hr.

Guanzon!' obtained 6.7 V o yield with denaturated alcohol als solvent. Resales"" obtained 14.6 Vocrude wax by extracting it from air-dried cakes using benzene as a solvent. Garrucho and GuiUen-E~calante~ reported 24.25 010 yield by extracting sugar cane wax from even-dried and sun-dried cakes using absolute alcohol. Rosalesl' refined the wax by the method of Swel2~on'~. Vinh and Vthneuva'" extracted wax using petro- leum ether and analyzed the organic matter, crude wax, total nitrogen, PO and CaO of different filter press cakes.

In Egypt Abdal-Akher et al.' reported 10.1-20.5 OIo yield by extracting sugar cane wax using petroleum benzene. Noana- lysis of the cane wax obtained from filter press from Egyptian cane sugar factories has been published.

The present study concerns with a process of extracting wax from filter press cakes from different sugar cane facto- ries. The speed and ease of extractionusing different solvents were compared. Both the crude and refined wax were ana- lyzed and the results compared with Camauba wax and other hard waxes, such as Louisiana and Japan wax.

M a t e r i a l s a n d M e t h o d s

Wax.

The following materials were used in this study: 1. Filter press cakes were taken from the following Egyptian

cane sugar factories: Edfu, (&,Nag Hamady,and Dishna. 2. Solvents: Toluene, naphtalene, acetone, gasoline, denatur-

ated and refined alcohol. 3. Chemicals: 95 Yo ethyl alcohol, 1 % hydrochlorid acid, 1 %

nitric acid, potassium hydroxide, isopropyl alcohol, phe- nolphthalein, sodium hydroxide, sodium hydrochloride, and sulphur dioxide. All chemicals were obtained from Merck, West Germany.

E x p e r i m e n t a1 7. Processing equipment

A 1000 ml Erlenmeyer flask was placed over a water bath. The flask was fdedwitharubberstopperwith2 holes,onefor condenser and theother for glass tubingfittedwithaclothfil- ter that extended to the bottom of the flask and delivered the extract to 2000 ml florence flask. The rubber stopper of the florence flask had 4 holes for: a) the tube from the Erlenmeyer flask, b) a tube connecting the condenser and the florence receiveqc) athermometerand d) anexhaust-tube forsuction.

Some capillary tubes were placed in florence flask to prevent bumping. The florence flask was placed on heating metal which was electrically heated at 110 V and regulated. A ther- mometer was hung over the water in the water bath to con- trol the temperature of the mixture.

For the fractional crystallization of the wax an oven and a regulated incubator were used. The melting point was deter- mined by using Kofler Micro Hot stage equipment.

2. Extraction ofthe crude wax The different press cakes were dried at 400 C for five days,

toremove someofthemoisturewhichmight causefermenta- tion. They were then passed through a 20 mesh size and kept in bottles. The moisture content was determined.

About 200 g of the filter press cake were placed in the Erlenmeyer flask and wax was extracted using different sol- vents. The proportion of the dried material to the solvent was 1 : 6 to 1 : 8. The hot extracts were filtered using a funnel with a hot water jacket. The temperature of mixture was kept bet- ween 75' to 85' C. After every thirdcontinuous extraction 10 ml aliquot portions of the extract were pipetted out and the amount of wax was determined by heating in the oven at a temperature above the boiling point of the solvent. The waxes obtained were dried first at 90' C and then at 105' C.

3. Separation ofthe f a g oilfiom wax The wax extracts were allowed to stand in a regulated

incubator. The temperature was gradually lowered to deter- mine the crystallization point of wax.

4. Refinirg of the wax The crude wax was treated with the following decolouriz-

ing agents: solutions of 0.2 sodium hydrochloride, dilute nitric acid, chlorine gas, acetone and sulphur dioxide.

For separation of the fatty oil fraction, the wax was re- fluxed for two hours with a mixture of 1 : 1 of 1 "/o hydrochloric acid and 1 % nitric acid. Another portion of crude wax was boiled with acetone. The acetone containing the fatty acid portion which passed through the filter paper after filtration was collected, evaporated to dryness, dried at 10fiO C and weighed.

The crude wax was dissolved by heating, filtered while hot, and crystallized at room temperature. It was again fil- tered to remove any alcohol, air dried and weighed. Then the dried wax was redissolved in hot acetone and filtered. Any excess of acetone was evaporated off. The wax was reprecipi- tated. Finally the precipitated wax was washed 3 times with cold acetone and dried at 105' C.

5. Chemical analysis of crude and refined wax The chemical and physical constants of the Edfu wax

using alcohol as solvent were determined on a moisture free basis.

Ash content: The ash content was determined by ip t ing samples of wax, previously dried at 105' C.

Iodine value: About 1 g of wax was analyzed for the iodine number using the A.O.A.C. method'.

Saponification number: About 2.5 g of the sample which was previously dried at 105' C were placed in an Erlenmeyer flask together with 25 ml of0.5 N alcoholic potassium hydro- xide. The procedure given by the A.O.A.C. method2 was fol- lowed.

FETTE . SEIFEN . ANSTRICHMITTEL 86. Jahrgang Nr. 6 1984 248

Acid number: About 2.5 g of dried wax were placed in an Erlenmeyer flask and dissolved in 50 ml of isopropyl alcohol. The mixture was heated in order to melt the wax. One drop of phenolphthalein indicator was added and mixture imme- diately titrated with standard sodium hydroxide while hot or near boiling point.

Acetyl value: About 7.5 g of the dried sample were re- fluxed with 12.5 d of acetic anhydride for a period of 2.5 hrs. The resulting products were well washed with warm water and dried in the oven at 105' C. About 2 g of the acetylated wax were determined using the A.O.A.C. method'.

Specific gravity: The specific gravity was determined by melting the wax, and with the aid of a stirring rod, globules of 1 mm in diameter were formed on a moist, cold porcelain sur- face. The globules were put in a glass cylinder, a mixture of alcohol and water was added in such a way that the globules remained suspended in the liquid. The specific gravity of this liquid was determined using a Westphal balance. Two tempe- ratures were used, 15.5' and 300 C. The mixture of alcohol and water was cooled to 15.5O C in a low temperature incu- bator before the determination. At 30'C the specific gravity of the wax was determined. Melting points: The melting point apparatus was heated prior to the actual determination of the melting point.

Removal of solvent: Samples were heated at 105O C to determine the percentage loss of weight of the wax.

R e s u l t s a n d Discuss ion Before the extraction of the crude wax, the filter press cake

was dried to air stability. The moisture content before drymg varied up to 85 %.The average moisture content after drying was 8.95%.

The results of the extraction of wax from the different samples using different solvents are given in Table 1. It took 20 to 30 min. to extract the wax from 200 g of sample using naphtalene or toluene as solvent, and 40 min. to extract the same with the fractionated gasoline. By using alcohol as sol- vent it tookabout I h . tocompleteoneextraction. It wasrela- tively easier to extract wax whenusing naphtalene or toluene than gasoline or alcohol.

Table 1

Egyptian Csude War (%) Obtuimd 6.v Extraction with Direrent Solventc

Oven Solvent Temp. Nag

O C Edh Qus Dishna Hamady

Gasoline 105 13.05 12.10 10.50 11.15 Gasoline fraction 120 13.06 12.05 10.60 11.00 Naphtalene 145 14.05 12.35 11.45 11.85 Toluene 120 14.55 12.65 11.65 12.00 Denaturated alcohol 90 13.90 12.05 10.95 11.45 Refined alcohol 105 13.56 12.15 10.79 11.76

Fractionation of the wax obtained after extraction was started at 75O C and the temperature gradually lowered to O O C . The greater portion of the wax from Edfu and @s samples can be crystallized at 3OOC. This will give a very cheap wax free from fatty matter.

With toluene or naphtdene as solvent, wax can be obtained after the temperature has been lowered at 15O C, which means more expense as there will be need of refriger- ation to lower the temperature.

The Edfu wax obtained by extraction with refined alcohol was sticky hard and heavy from 45' to 2.5' C. It became softer

FETTE . SEIFEN 86.Ja-g

ANSTRICHMITTEL Nr 6 1984

and granular which its colour changed from dark green to very pale green as the temperature was lowered to 0' C. The @s wax was hard, olive green at 45' to 20' C, turned granu- lar or powdery and greenish-yellow at a lower temperature. Fraction of the Nag Hamady wax extracted with toluene produced a sticky but hard light coloured wax at 20' to 25' C, but it turned granular as the temperature was lowered to 0' C. On the other hand the Dishna wax obtained by extrac- tion with alcohol was hard at 200 C, less sticky, but turned dark geen at lower temperature.

The amount of wax obtained by crystallization was lower than the amount of wax obtained by evaporation of the sol- vent because in the latter case the wax obtained contained substances soluble in alcohol such as mineral salts, lower fatty acids, and alcohols.

The refining process, using 4 to 5 portions of acetone,gave 27.3% of fatty matter for the Edfu sample. The @s sample gave 27.12%. These were approximately the same as the result obtained by Bulch4 which was 30% fats.

The amount of refined wax obtained using 4 to 5 ml por- tions of acetone, which was also about 6 times the weight of the original wax, was 68.85% for the Edfu sample and 67.76 O/o for @s sample.

The results of the analysis of the crude and refined wax from the two samples Edfu and @s are given in Table 2. These values are compared with known values of commer- cial waxes and those obtained by Bulch4.

The melting point of the crude waxes had a very wide range showing the presence of many impurities. The specific gravity obtained at 15.5' C was greater than that found at 30' C.

It was noted that the saponification values decreased in both cases, showing the separation of appreciable amounts of fatty oil fractions from the refined wax.

Since the acid value of refined wax was much lower than that of the crude wax we can say that the fatty acids were almost removed during the process of refining. This Egyptian cane sugar waxes can be utilized in paper, ink, coating, var- nished, pharmaceuticals, cosmetics, and fertilizer industries.

C o n c l u s i o n Wax from four different Egyptian sugar cane filter press

cakes was obtained by continuous extraction. Samples ofthe press cake from the Edfu and @s gave a high percentage of wax with alcohol, toluene or naphtalene as solvents. Other samples obtained from Nag Hamady and D i s h gave a small yield.

Extracts with toluene and naphtalene were brown in colour which was hard to remove even after bleaching with chlorine or sulphur dioxide. Extracts with alcohol as solvent, after evaporation to dryness,were dark green in colour due to the presence of chlorophyll and were hard to bleach.

On the other hand, the wax separated by fractional cry- stallization from alcohol was light green in colour.This colour may be removed by the or- method of bleaching.

Refining with acetone showed that most of colour can be removed without bleaching the wax, giving its nice creamy colour. The advantage of this method of refining lies in the fact that the alcohol extract can be hardily treated with ace- tone in a short time, thus eliminating the possibility of dis- solving the extracted wax with the solvent before treating with acetone as described by Balch'.

249

Theair-driedproduct waspale yellow after treatment with acetone which removed the chlorophyll together with the fatty oil. Th~s refined wax can be obtained in granular form which has a higher price than the ordinary solid variety. Frac- tionation of the sugar cane wax obtained from the different samples showed that a hard, brittle wax can be obtained at a temperature between 45' C to 20' C. Below this tempera-

ture, the Wax granular and Powdery although the colour becomes much lighter.

From theresultsofthisinvestigations,it was found that the wax obtained from Egyptian sugar cane filter press cake has properties similar to those of camauba and other commercial hard waxes.

Table 2

Chemical and Physical A@tks of Egyptian Cane Crude War and Rejked War Compared with the Commercial Wares

Chemical and Physical Commercial Crude Egyptian Crude Commercial Egyptian Refined Properties WaX WaX Refined Wax

WaX

Edfu @s Edfu Q l S

Ash (0%)) Louisiana 1.46 1.80 1.70 0.6 1 0.82 0.78 Iodine value Louisiana 37.41 32.30 33.10 1 1 .oo 12.55 12.15 Saponafication No Louisiana 70.90 66.20 67.50 34.00 34.70 35.60 Acid No Camauba 24.26 28.70 29.50 7.50 7.60 7.65 Acetyl value Camauba 92.00 94.00 94.58 49.50 - -

Melting Point (" C) Louisiana 84-85 77-8 1 74-78 85 80-83 79-82 Specific Gravity at 15' C Japan 0.970 0.900 0.890 0.997 0.997 0.956

L i t e r a t u r e ' M . Abdal-Akher et al., Chem. Mikrobiol. Tech. Lebensm. 5, 42

[ 19771. Association of Official Agricultural Chemists, "Official and Ten- tative Methods of Analysis", 5'h ed., A.O.A.C., Washington D.C. 1940.

' Avequin, Ann. Chim. Phys. 75,218 [ 19401. ' R . TBalch, Sugar Research FoundationTechnol., Report Ser. 103,

' C. Broeg and R . I: Bakh, US.€? 449107 (1948). " Chcher, Internat. SugarJ. 18,22 [ 19161.

S. Garrucho and Guilkn-Escahnh, A Re.) 2 [ 19611 ; C.A. 59,15468 a [ l963r W Goepfert, U.S.F! 239893 (1946).

62 [ 19471.

Newsletter (Philippine

!' G . Guawon, Sugar News 8,877 [ 19271. ' O C. L. Locsin, Sugar News 20,467 [ 19271. ' I E. S. McLoud, U.S.F! 2456641 (1948). l 2 K. Rao and G. Guptu, Proceedings of the loth Ann. Convention

Sugar Techn. Assoc. India, part II,79-82 (1941). H. Ratah, Proceedings Philippine Sugar Techn. Conv. 50 [ 19501 ; C.A. 51,12524 e [ 19571.

L. X. Vinh and L. R Vilhneuva, Philippine Agriculturist 44,236 [ 19601 ; C.A. 55,228875 [ 19611.

I' 0. J. Swensun, US.€! 2464189 (1949).

Received 28'h June 1983.

Rationalisierung der Oberflachenveredelung

Vbn H. H e i n e r *

Eine wichtige Rolle bei der Rationalisierung der Oberila- chenveredelung in der Holztechnik spielen Schnelltrock- nungsverfahren, Impriignieren und Lackieren. Um beim TrocknungsprozeB so kostengiinstig wie moglich zu arbeiten, miissen Energre-, Zeit- und Investitionsaufwand in ein ver- niinftiges Verhaltnis gebracht werden. Verschiedene Trock- nungssysteme sollen daher im folgenden Beitrag verglichen werden. Bei der Oberilachenveredelung haben die Anlagen- planer eine Gliederung in funf Technologie-Bereiche vor- genommen. Die Auswahlknterienfiir Tauchen,Fluten,Sprit- zen,Trocknung und Transport werden ebenfalls beschrieben.

Der Schnittholzverbrauch zeigt seit Jahren steigende Ten- denz. Allein fiir die Bundesrepublik belauft er sich derzeit auf 12 bis 15 Millionenm3/Jahr. Die Verwendung des Massivhol- zes zum Beispiel als Fenster, Turen, Treppen, Leimbinder, Fertighauselemente oder Profilbretter, im weiten Bereich des Innenausbaues und natiirlich auch in der Mobelproduktion erfordert eine genau definierte Holzfeuchte, die durch for-

* Anschrift des Verfassers: H. Heimr, An Neuenhofen 24,4150 Kre- feld-Bockurn.

cierte ,kiinstliche" Trocknung erzielt werden muO. Wegen der komplizierten Handhabung sowie der hohen Investi- tions- und Betriebskosten bleibt die Hochfrequenztrock- nung wenigen Spezialfallen vorbehalten.

U i c h verhalt es sich laut Eisenmann, Boblingen, mit der z. Z. besonders von italienischen Anlagebauern ins Gespriich gebrachten Vakuumtrocknung, die m a r k u m Trockenzei- ten ausweisen konne, dafiir aber apparativ aufwendig sei. Hochtemperaturtrocknung und Kondensationstrocknung als Unterbereiche der Konvektionstrocknung sind ebenfalls nur fiir Spezialgebiete interessant. Bei der Hochtemperatur- trocknung mit HeiI3dampf iiber 100 bis ca. 130 ' C htingt die Einsatzmoglichkeit prima vom zu trocknenden Holz ab. In der Praxis von Bedeutung ist zum Beispiel die Trocknung groBer Mengen Fichten- und Tannenbretter 16 bis 24 mm dick, die anschlieDend zu Mittellagen fiir Tischlerplattenver- arbeitet werden.

Die Kondensationstrocknung hingegen, in den letzten Jahren geradezu als eine Art Modebegnffpropagiert,ist zwar rein theoretisch fiirjede Holzart geeignet,aber keineswegs so giinstig wie haufig dargestellt. Durch die verfahrensbedingt

86. Jahrgang Nr 6 1984 FETTE . SEIFEN ANSTRICHMITTEI.

250