New Catalysts in Technology of Hydrogenation of Cotton Oil Journal of Experimental Food Chemistry

Improvement of quality of fats can be carried out by change of triglyceride structure of oils and fats in the various ways of their modification. Now the basic methods of modification of oils and fats are technology hydrogenation, hydro inter-esterification and interesterification [1]. In industrial practice most accepted way of catalyst modifications of vegetable oils and fats is the technology of hydrogenation with use of various types of catalysts [2]. Despite large number of the catalysts offered in technology of catalyst modification of cotton oil till this moment there are no concrete recommendations for choice the most effective catalyst allowing considerably to raise quality and to provide food safety of finished food fats. Therefore widely scale researches in the field of development of new technologies and hydrogenation catalysts which main advantage is quality maintenance and food safety catalyst modified fats proceed [3].


Introduction
Improvement of quality of fats can be carried out by change of triglyceride structure of oils and fats in the various ways of their modification. Now the basic methods of modification of oils and fats are technology hydrogenation, hydro inter-esterification and interesterification [1]. In industrial practice most accepted way of catalyst modifications of vegetable oils and fats is the technology of hydrogenation with use of various types of catalysts [2]. Despite large number of the catalysts offered in technology of catalyst modification of cotton oil till this moment there are no concrete recommendations for choice the most effective catalyst allowing considerably to raise quality and to provide food safety of finished food fats. Therefore widely scale researches in the field of development of new technologies and hydrogenation catalysts which main advantage is quality maintenance and food safety catalyst modified fats proceed [3].

Purpose of work
The work is directed on improvement of quality and maintenance of food safety of fat-oil, received by hydrogenation of cotton oil, by selection of scientifically valid highly effective technologies and catalyst systems, allowing to lower the maintenance a trance-isomerized fat acids and to regulate necessary arrangement of fat acids in triacylglycerides of food fats.

Research course
Object of research were the refined deodorized cotton oil, powdery and stationary floatable catalyst systems on the basis of nickel, copper and various proctored additives, possessing high hydrogenating properties. Researches on catalyst modifications of cotton oil and studying of the basic kinetic laws of process in flowing conditions in the presence of stationary floatable catalysts is used plant of a high pressure with reactors of columned type [4]. For the analysis and an estimation of quality, the physical and chemical characteristic, food safety of raw materials, intermediate materials, hydrogenated fat-oil and products on their basis are used modern physical, chemical and physical-chemical methods and mathematical processing of the received experimental data [5,6].

Results and Discussion
In researches on catalyst modifications of cotton oil are used various catalyst systems of new modification. Also were analysed stationary floatable and powdery (Nisosel-8 containing nickel and copper salts) catalysts on the basis of nickel, copper and promrtored additives. The stationary floatable catalysts, containing one and two promrtored additives are analysed. Componential structure of the analysed stationary floatable catalysts is resulted in Tables 1 and 2.    Table 3: Componental structure of new types of nickel-copperaluminum of alloys, with the combined combination of two proctored additives.
As the most effective powdery catalyst it is used catalyst "Nysosel-800" made by firm Engelhard in Holland [7]. In researches are studied nickel-copper-aluminium (25.0:25.0:46.0-48.5) alloys with the joint combination of two promrtored additives (Table 3). Catalyst hydrogenation of cotton oil were carried out in identical technological modes (Table 4) at which the basic properties of stationary floatable catalysts are established. The basic physical and chemical characteristics of catalyst "Nysosel-800" are resulted in Tables 5 and 6.

Temperature°С 200
Pressure kPа 300 Volume velocity of feed of raw materials h -1 1 Volume velocity of feed of hydrogen h -1 60 Catalyst volume ml 1000 The average size of particles of the catalyst mm 6  Research of influence of temperature for velocity of saturation of cotton oil at presence of non-promotor and promotor nickel-copperaluminum catalysts carried out at following conditions: pressure 300 kPа, velocity of feed of hydrogen of 60 ml h -1 , volume velocity of feed of oil 1.2 h -1 . Results of research are presented at Table 7   As we see from Table 7, with rise in temperature velocity of saturation increases, thus intensive growth of velocity is observed at 200°С, even at 120-180°С. Apparent activation energy is approximately equal to 15 kJ/mol. At more heat this size decrease even more sharply that specifies in limitation of process by hydrogen diffusion [8]. Pressure of hydrogen has the greatest influence of fat-oil qualitative measures in the course of continuous hydrogenation. In these conditions the greatest influence on selectivity of process renders a combination of the raised temperatures to enough high volume velocity on oil. In this connection, particular interest has data, received at continuous operation of hydrogenation plants (Tables 8-10).

Modification conditions
Fatty-acid structure Factor of selectivity, %

Conclusions
It is established that the optimal catalyst systems for production of firm food fat-oil of high-quality and food safety are powdery and developed stationary floatable catalysts on the basis of nickel, copper and promotor additives. Such catalyst systems have allowed to lower quantity of trance-isomerized fat acids in fat-oil to 5-7% and to provide maintenance constancy of linoleic acids. The most comprehensible technological modes of manufacture of the highquality hydrogenated fats were temperature 180°С, pressure 100 kPa and volume velocity of feed of oil 1.2-1.5 h -1 . Such conditions have allowed lowering the quantitative maintenance of trance-isomerized mono-nonsaturated fat acids in food fat-oil.