CC BY
27
Section 2. Food processing industry
Akhmedov Azimjon Normuminovich, c.t.s., ass.prof. Head of the department"Chemistry" (KEEI) E-mail: a.ahmedov80@mail.ru; azim-10-86@mail.ru
INCREASING THE TECHNOLOGY OF LIGHTLY REFINED OIL OBTAINED FROM LOW-GRADE COTTON SEEDS
Abstract. This article introduces the technology of initial whitening of low-grade cotton seeds. As a result of the initial injection of urea-modified soil-based adsorbents (MSBA), the amount of cotton oil, acid content and sediment lubricant decreased.
Keywords: gossypol, modified carbamide clay adsorbent, flock but standard newly buttermilk chitlada olingan my, carbamide, pre-lightening.
Introduction
Regarding to the number, a significant amount of low-grade cotton seeds is supplied to the enterprises of the oil and fat industry of the country, processing of which is accompanied by large losses of oil and reagents.
The technology used to produce cottonseed oil is used to process the first and second varieties of cotton seeds and allows to obtain oil and cakes that meet the requirements of the relevant standards [1].
Analysis of crude oils derived from low-grade cotton seeds shows that they contain a significant amount of coloring matter (gossypol, chlorophyll and their derivatives), free fatty acids and other components [2]. Therefore, the selection of a more effective adsorbent for the clarification of these oils is an important scientific and practical task.
Our laboratory studies on the preliminary clarification of these oils showed that it is advisable to use ICHA for this purpose [3].
Cotton oils obtained by pressing and extraction methods from low-grade and non-standard seeds, in most cases, are of dark color and are practically not visible on the Lovibond color meter. This is due to
the high content of gossypol, chlorophyll and their derivatives, as well as non-fatty substances.
The existing technology of refining cotton oils obtained from low-grade seeds involves the use of alkaline solutions with a high concentration (400 g /l or more) in an excess amount (150% or more), which leads to significant losses of oil in soap stock and a decrease in the yield of the resulting product.
Improving the technology of obtaining refined pressing and extraction oils from low-grade and non-standard cotton seeds using the method of pre-clarification of raw (black) oils with the help of carbamide-modified clay adsorbent is considered an urgent and practically important task.
At present, domestic and foreign scientists have carried out and are conducting research on the extraction of related substances (including gossypol and its derivatives) from the composition of raw cotton oils obtained by pressing and extraction methods. In the works of A. S. Sadykov, A. L. Mark-man, V. P. Rzhekhin, A. G. Sergeev, A. I. Glushchen-kova, A. I. Ismailov, A. T. Ilyasov and many others. refining cotton oils with solutions of caustic soda,
carbamide and other alkaline reagents. In these methods, due to the high consumption of alkaline reagents, a significant portion of triglycerides is saponified, which adversely affects the yield of the resulting oil and its quality.
Research objective: Development of technology for pre-clarification of raw oils obtained from low-grade and non-standard cotton seeds using a carbamide-modified clay adsorbent.
Objects and research methods: The carbamide-modified clay adsorbents were obtained by impregnating them with a 30% urea solution, followed by drying at 95-1000 °C to a moisture content of 7-8%,
and they were used for the preliminary clarification of raw cotton oils. We have proposed the choice of the location of the input MSBA in the technological scheme of preliminary cleaning of raw press oils.
A technological scheme was created at JSC "Ko-son Oil-Extraction" for clarifying raw cotton oil with a clay adsorbent modified with urea. A distinctive feature of this scheme from the well-known is that at the beginning of the supply line of raw oils in the collection - a fuse tank (bush), a hopper is installed, from which the MCA is supplied to the crude oil, in the required amount, depending on the color of the original oil.
crushing^
......V
production unit
|/\/\/\/\/\/\/\ /\ /\( j/\/\/\/\/\/\/\/
^................. 1/........
MSBA
oil refination
14/
-> 13
12
yX/X/X/X/X/X/X/X/X/^X/X/X/X/^j K/X/X/l . „ _ _ - - " - - - " ■
Figure 1. Technological scheme of pre-clarification of raw cotton oil with carbamide-modified clay adsorbent: 1 - steam worm screw; 2 - brazier; 3 - stirrer; 4 - press granulators; 5, 6, 9 and 14 - screw; 7 - fuse tank; 8 - noria; 10 - bunker; 11 - valve; 12 - pump; 13 - filter press
Figure 1 presents the proposed technological where the pulp enters the press granulators 4, then
scheme for clarification of crude oils, using ICGA. through the auger 5 the cake is sent to the extraction
This scheme functions as follows: on auger 1 moist- plant. For the preliminary clarification of crude oils,
ened cotton mint enters the roaster 2, which is from the hopper 10 through the valve 11 to the col-
equipped with an engine and an agitator 3. From lecting auger of crude oil 6, the loam adsorbent from
3
7
Angre kaolin (MCA-4), modified with carbamide, is screw 9 is sent to the roaster 2, and oil is pumped
fed to the batcher in an amount of 2-6% by weight into the frame filter press 13 for filtration, from
of oil. Further, crude press oil is fed through screw 6 which they are sent to alkaline refining, and the sedi-
into the fuse tank 7, where it is cleaned of mechani- ment from the filter press 13 goes to fuza-tank 7.В
cal impurities and sludge. From the fuzo tank 7, the (табл. 1) представлены технологический режим
return product (fuz) according to noria 8 and the предварительного осветления сырых масел.
Table 1. - Нормы технологического процесса предварительного осветления сырого масла с использованием МКГА
Name of processes and operations Unit. Meanings
I. Moisture Thermal Cotton Mint Treatment:
- minting of the myatka % 15-17
- humidity of the mint % 7-9
- quantity of the return goods (fuse) % 5-7
II. Pressing and pelletizing:
- the temperature of the pulp
- pulp moisture 0С 95-100
- dimensions of grates: % 7.5-9.5
- first mm 1.0
- the second mm 0.75
- the third mm 0.45
- fourth mm 0.35
- the size of the matrix for granulation mm 10-12
III. Preliminary clarification of crude oils:
- oil temperature 0С 80-90
- number of MKGA % 5
- time Per hour 0.4-0.6
IV. Fuza separation:
- oil temperature 0С 55-70
- speed of turns of a fuse tank /min 50-60
V. Oil Filtration:
- oil temperature 0С 70-75
- press pressure MPa 0.03-0.05
Probably, carbamide with gossiphosphatides according to the substitution principle has the following interaction formula (1):
In addition, urea can form compounds with free fatty acids, their sodium or potassium salts, as well as Schiff bases. Such a complex mechanism of interaction of urea with other components of raw cottonseed oil in the complex is reflected in its color.
Results and their discussion: From the data of Table 1 it can be seen that, in contrast to the traditional technology for producing cottonseed oil, the proposed process introduces the process of clarifying crude oils using an MCA. At the same time, the adjustable parameters of the process of preliminary clarification of raw oils can be the amount of injected ICA and the time of preliminary clarification, which vary in the proposed technological scheme (Fig. 1).
O-R
CH2-CH2-N=CH oh
HO HO
O-R
OH HC=N-CH2-CH2
OH
NH2
+2C=O->
OH I
NH2
CH H H3C CH3
H CH H /\ H3C CH3
gossiphospatid carbamid
NH2-CO-N=CH OH OH HC=N-CO-NH2
HO
HO
OH
O-R
+ 2NH2-CH2-CH2
CH /\
H3C CH3
H
OH
H
CH
H3C CH3
decarbamid-gossipol
phospatid
(1)
It is known that the intensive dark color of cottonseed oil is given by the products of changes in native gossypol, as well as melanoidin compounds, which are formed during the self-heating of seeds and heat treatment of mints. In addition, in the process of moisture-heat treatment of cotton myatka, complex compounds of derivatives not only of gos-sypol, but also of chlorophyll are formed, which also increase the color of the resulting crude oils.
The formation of carbamide compounds with native gossypol is apparently due to the participa-
tion of aldehyde groups of the latter, although other mechanisms of their interaction are possible.
In addition, urea can form compounds with free fatty acids, their sodium salts, etc. This complex mechanism of interaction of urea with the accompanying components of raw cottonseed oil in the complex is reflected in its color and other indicators.
In [4], it was shown that the optimal amount of carbide-modified clay adsorbent MKHA-4 when bleaching crude oil obtained from low-grade cotton seeds is 5% by weight.
Table 2. - Indicators of cotton oils, purified in the usual way and pre-clarified using ICGA-4 in the amount of 5% of the total mass of raw materials
Oil derived from:
Name of cotton oil indicators low grade seed mixtures of low-grade and nonstandard seeds
1 2 3
Crude oil, purified in the usual way (control):
Chroma, in 1 cm layer with 70 yellow
units:
- red edinet 65.5 74.3
- siny unity Acid number, mg KOH / g 3.7 5.3 6.5 6.1
Sludge content,% 0.94 1.85
1 2 3
Oil, pre-clarified using ICA:
Chroma, in 1 cm layer with 70 yellow
units:
- red edinet 36.7 42.4
- siny unity 1.5 2.8
Acid number, mg KOH/g 3.2 4.0
Sludge content,% 0.73 0.98
Table 2 presents the results ofpre-clarification of crude oils using thermally activated modified adsorbents, for example ICA-4.
From (table 2) it can be seen that the preliminary clarification of crude oils, using 5% of the mass of oil MKGA-4, significantly reduced the color of the oils, their acid numbers and the content of sludge in them. This is explained by the fact that the carbamide-modified clay adsorbent absorbs substances that stain cotton oil and removes them when separating and filtering the oil.
It is known that at present carbamide is used in animal husbandry to enrich feed with non-protein nitrogen. Bentonites and kaolins are also used in the preparation of mixed feed for various purposes. Therefore, the choice of urea and natural clays in obtaining a modified adsorbent becomes reasonable.
Conclusions: Thus, the use of carbamide-modified clay adsorbent MKHA-4 in the process of preliminary clarification of raw oils obtained from low-grade cotton seeds has significantly reduced their color, sludge content and acid number.
References:
1. Kopeykovsky V. M., Danilchuk S. I., Garbuzova G. I. and others. The production technology ofvegetable oils.- M .: Light and food industry, 1982. - 416 p.
2. Akhmedov A. N., Abdirakhimov A. S., Dustmurodova S. Zh. Physico-chemical indicators of the prepeso oil obtained from low-grade cotton seeds // "Chemistry and chemical technologist".-Tashkent, 2018. - No. 1. - P. 75-78.
3. Akhmedov A. N., Suvanova F. U., Abdurakhimov S. A., Ikromov O. A. Investigation of the process of refining oils obtained from low-grade cotton seeds // "Chemistry and chemical technologist". - Tashkent, 2014. - No. 3. - P. 69-72.
4. Akhmedov A. N. Improving the technology of complex refining of oils obtained from low-grade cotton seeds. Dissertation of c.t.s.- Karshi, 2012. - 110 p.
