Possibility of bleaching sunflower oil with synthetic zeolite

In this paper, the possibilities and effects of using domestic industrially produced zeolite for bleaching crude sunflower oil, compared to imported commercial bleaching earth, were examined. The parameters of the bleaching process in laboratory conditions were: temperature 95°C, contact time 30 min, and mass fractions of bleaching agent in oil: 0.2, 1, 2 and 3%. The following methods were used to characterize the bleaching agents: XRD, FTIR, BET and SEM/EDS. The bleaching efficiency parameters were determined by laboratory methods prescribed by the relevant ordinance on edible vegetable oils, and included: soap content, peroxide value and fatty acid composition. The results of the research showed that the effects of bleaching sunflower oil with synthetic zeolite are similar to the effects of bleaching with imported commercial bleaching earth, with the former showing a slightly higher effectiveness in reducing the peroxide value

Efficiency of degreasing by dishwashing detergents

Consumption of agents for manual and machine washing of dishes is constantly increasing. Although the growth of the use of dishwashers is evident, hand dishwashing is still dominant in our region. A good dishwashing detergent must effectively remove food residues and degrease the surface of dishes, made of different materials, while the surfaces of washed dishes should remain smooth, shiny with a pleasant smell of freshness. The requirements of consumers-users of these funds are, in addition to the listed basic functions, also practicality of handling and dosing, pleasant smell and mild action on the hands and acceptable price. The aim of this paper is to examine the degreasing efficiency of commercial detergents from our market on four types of fats. In addition to commercial dishwashing detergents, whose composition is known only roughly indicated in the producer declaration, was tested a laboratory prepared sample with exactly known composition. All tests of the degreasing ability of dishes with different types of impurities were performed under the same conditions with a change in the concentration and type of detergent, and according to the method used by some industrial detergent manufacturers. It was found that in addition to the concentration of detergent in the washing solution, the degreasing efficiency is affected by the type and concentration of surfactants, as well as auxiliary components that are part of the product

TESTING OF SMALL HOUSEHOLD BIOMASS BOILERS FROM THE ASPECT OF WASTE GAS EMISSIONS

The use of biomass for energetic purposes is actual issue from different aspect of views, such as economy, used technologies, combustion specifications, environmental issues, etc. Different types of biomass are available on the market today. During the combustion process in furnaces, these types of biomass behave differently due to their specific physicochemical properties. In this research, used biomass types were wood biomass, soybean straw and chamomile waste from medicinal herbs processing. Pellet combustion was performed in a commercial furnace that was designed to heat the living space by burning wood pellets. Furnace was installed with measurement system for emissions of combustion products. The current law regulation of the Republic of Srpska in the field of environmental protection does not include testing of emissions of combustion products for plants with power less than 100 kW. In this research, the influence of pellet type on concentrations of carbon monoxide and nitrogen oxides was investigated, as well as the volume content of oxygen in the waste gas for plants with power less than 100 kW. Also, it was investigated whether the addition of additives (clay, kaolinite, bentonite), used to improve the melting characteristics of ash, has an effect on reducing the emission of combustion products. The results obtained by measuring the gas emissions are compared with the standard EN 14785 which is related to the emission of carbon monoxide and nitrogen oxides. During this research, characteristic of ash left after combustion of tested pellets was examined. According to these examinations, it can be pointed out that potential problems can occur when burning these types of pellets in small household heating furnaces

NUTRITIONAL ASSESSMENT OF PATIENTS WITH PRIMARY PROGRESSIVE DEMENTIA AT THE TIME OF DIAGNOSIS

Background: patients with different types of dementia may experience changes in nutritional status, which are manifested by specific eating habits. The aim of this study was to determine the nutritional status and eating habits of patients at the time of confirmed diagnosis of primary progressive dementia. Subject and methods: The study included 40 outpatients (63% women) diagnosed with either form of dementia. The mean age at diagnosis was 776 years and the mean time between the onset of first symptoms of the disease and diagnosis was 3-36 months. Nutritional assessment was determined at the time of confirmed diagnoses and included dietary habits (non-quantitative modified food frequency questionnaire (FFQ)), anthropometric (body weight and height and body mass index-BMI) and biochemical parameters (serum concentrations of vitamin B12, folic acid and 25-hydroxy vitamin D). Dietary habits were collected over a 12- month period with the help of a spouse or close family member. Results: The results showed that none of the outpatients were malnourished, the largest number of outpatients (43%) were in the normal body mass category followed by 33% in the overweight category. The results of this study confirmed previous findings of higher preference for sweet foods observed in 53% of patients with dementia. Low status of vitamin B12 was observed in 57% of outpatients, folic acid in 24% and 25 (OH) D in 75% of outpatients. Lower frequency of consumption of dark green leafy vegetables and lower consumption of poultry meat, fish and eggs could have an impact on nutrient deficiency. Conclusions: The poor nutritional status of outpatients with primary progressive dementia is associated with unhealthy dietary habits that may lead to micronutrient deficiencies. Dietary monitoring and intervention should be initiated immediately after the diagnosis of primary progressive dementia with the goal of reducing nutritional deficiencies and preventing further and more severe impairment of cognitive function

NUTRITIONAL ASSESSMENT OF PATIENTS WITH PRIMARY PROGRESSIVE DEMENTIA AT THE TIME OF DIAGNOSIS

Background: patients with different types of dementia may experience changes in nutritional status, which are manifested by specific eating habits. The aim of this study was to determine the nutritional status and eating habits of patients at the time of confirmed diagnosis of primary progressive dementia. Subject and methods: The study included 40 outpatients (63% women) diagnosed with either form of dementia. The mean age at diagnosis was 776 years and the mean time between the onset of first symptoms of the disease and diagnosis was 3-36 months. Nutritional assessment was determined at the time of confirmed diagnoses and included dietary habits (non-quantitative modified food frequency questionnaire (FFQ)), anthropometric (body weight and height and body mass index-BMI) and biochemical parameters (serum concentrations of vitamin B12, folic acid and 25-hydroxy vitamin D). Dietary habits were collected over a 12- month period with the help of a spouse or close family member. Results: The results showed that none of the outpatients were malnourished, the largest number of outpatients (43%) were in the normal body mass category followed by 33% in the overweight category. The results of this study confirmed previous findings of higher preference for sweet foods observed in 53% of patients with dementia. Low status of vitamin B12 was observed in 57% of outpatients, folic acid in 24% and 25 (OH) D in 75% of outpatients. Lower frequency of consumption of dark green leafy vegetables and lower consumption of poultry meat, fish and eggs could have an impact on nutrient deficiency. Conclusions: The poor nutritional status of outpatients with primary progressive dementia is associated with unhealthy dietary habits that may lead to micronutrient deficiencies. Dietary monitoring and intervention should be initiated immediately after the diagnosis of primary progressive dementia with the goal of reducing nutritional deficiencies and preventing further and more severe impairment of cognitive function

Study of the dechroming of tanned leather wastes

According to European legislation, it is not possible to dump any chromium-containing waste in Europe. The minimization of wastes is a key element in that strategy. It involves the application of clean technologies: low and non-waste technologies. The tanning industry generates substantial quantities of chromium-containing solid waste in the form of shavings and trimmings. The recycling and reuse of those wastes must be the primary target in optimizing processes of the leather industry. The problem is in a satisfying chromium separation from collagen fibers. Common hydrolysis processes-alkaline or acidic-give gelatins containing residual chromium (III). By using an oxidation agent (H2O2) before alkaline hydrolysis, in was demonstrated that chromium from chromium-containing leather wastes can be almost fully recovered by the previous oxidation of Cr(III) to Cr(VI). This chromium can be reused in the tanning process. That would represent an economic saving. The best result of the dechroming process was a gelatin hydrolyzate with only 1.11 in respect to the initial amount

HIDROOBRADA KORIŠTENOG MOTORNOG ULJA PUTEM NiMo/Al2O3 KATALIZATORA

Korišteno motorno ulje je jedna od najčešće recikliranih sirovina. Rerafinacija korištenih ulja obezbjeđuje uštedu energetskih i petrohemijskih sirovina, prije svega sirove nafte, i smanjuje zagađenje životne sredine. U ovom radu izvršena su ispitivanja koja imaju za cilj da potvrde mišljenje da se rerafinacijom korištenih motornih ulja mogu dobiti bazna ulja po kvalitetu jednako vrijedna kao bazna ulja dobijena preradom sirove nafte.  Rerafinacija je izvršena katalitičkom hidrogenacijom na umjernim temperaturama i pritiscima, direktno poslije pripremnih faza i vakuum destilacije, uz upotrebu dva komercijalna katalizatora tipa NiMo/Al2O3. Ispitivanja su urađena na mješavini korištenih motornih ulja za putnička i komercijalna vozil

Resistance of the leather-rubber adhesive joint when making the shoe upper

The professional literature dealing with specific aspects of adhesive joints in the footwear industry is mainly devoted to the procedures of preparation, bonding and testing of the connection between the upper and the sole material of fashion and sports footwear. However, there is little research related to the requirements and quality testing of adhesive joints of shoe upper parts. Safety and occupational footwear, which is intended for specific occupations such as firefighters, police officers, soldiers and others, as such has specific requirements in terms of resistance to various types of solvents, high and/or low temperatures, shocks, etc., and in addition it should be comfortable and long-lasting. For these reasons, the upper of this type of footwear differs significantly from the footwear used in everyday life. It is usually a very complex construction and is made of a large number of different natural and artificial materials such as: leather, rubber, polyurethane, synthetic membranes, etc., which are interconnected by bonding or stitching. The aim of this study was to examine how the number of adhesive coatings and their characteristics affect the strength of the natural leather – rubber adhesive joint in the manufacture of shoes for special purposes. The strength of the leather-to-rubber adhesive joint depends significantly on the number of adhesive coatings and the viscosity of the adhesive

UTICAJ KISELINOM AKTIVIRANOG BENTONITA NA OKSIDACIONU STABILNOST HIDROKREKOVANIH BAZNIH ULJA

Hidrokrekovana bazna ulja se, u odnosu na klasična mineralna ulja, odlikuju smanjenom isparljivošću, nižim sadržajem ukupnih i policikličnih aromatskih ugljovodonika, kao i nižim sadržajem azotnih i sumpornih jedinjenja. Kao završna faza u proizvodnji hidrokrekovanih baznih ulja primjenjuju se hidrofinišing ili obrada adsorbentima. U procesu hidrofinišinga dolazi do hemijske transformacije nepoželjnih jedinjenja u poželjna, dok se u procesu obrade adsorbentima bazna ulja fizičko-hemijski vezuju na površinu adsorbenta pri čemu dolazi do neznatne promjene hemijskog sastava, koja dovodi do promjena nekih fizičko–hemijskih karakteristika. Rafinacijom adsorbentima dolazi do smanjenja sadržaja heteroelemenata i drugih polarnih jedinjenja, a efekat tih promjena je u funkciji od tipa i količine korištenog adsorbenta za rafinaciju. Osim toga, obrada hidrokrekovanih baznih ulja adsorbentima doprinosi zaštiti životne sredine, jer se smanjuje sadržaj nepoželjnih aromatskih jedinjenja, od kojih su neka toksična ili čak kancerogena. U industrijskoj praksi za obradu hidrokrekovanih baznih ulja koriste se različite vrste komercijalnih adsorbenata dobijenih aktivacijom montmorilonitnih glina na bazi alumosilikata. Efikasnost adsorbenata zavisi od veličine čestica, zapremine pora, kao i specifične površine koja se može povećati različitim postupcima aktivacije. U ovom radu ispitivana je oksidaciona stabilnost uzoraka hidrokrekovanih baznih ulja rafinisanih domaćim adsorbentom bentonitnog tipa i komercijalnom glinom. Prirodni bentonit je aktiviran sumpornom kiselinom u laboratorijskim uslovima. Ispitivanja su pokazala da je oksidaciona stabilnost ispitivanih hidrokrekovanih baznih ulja rafinisanih aktiviranim bentonitom slična ili jednaka oksidacionoj stabilnosti istih rafinisanih komercijalnom glinom

Methylene blue removal by adsorption on unmodified and modified wood sawdust

Adsorption, as an easy and effective technique, is widely used to remove a large number of dyes from aqueous solutions. Activated carbon is the most desirable adsorbent, but due to its high cost, its use is limited. Proving the possibility of adsorption and its efficiency performed on cheap adsorbents is a great challenge and interest of many researchers in the past few decades. In this paper, unmodified (P) and modified sawdust obtained in two ways (HCl treatment and NaOH treatment), labeled as PHCl and PNaOH, are used for the removal of the methylene blue dye. Adsorption experiments showed that the optimal time for adsorption is different, for the sample PNaOH – 30 min, for the sample P – 45 min, and for the sample PHCl – 60 min. By applying nonlinear kinetic models to the experimentally obtained data, it was found that the best model that describes this adsorption is pseudo-second-order model. By examining the effect of pH values on adsorption, different results were obtained (for samples P and PHCl the optimal pH value is pH=11, the PNaOH sample is effective in a wider range of pH values). The analysis of the effect adsorbent dose on adsorption process showed that the efficiency of dye removal decreases with increasing mass of adsorbents. The obtained values of the coefficient of determination in Freundlich's model for samples of unmodified (P) and modified sawdust (PNaOH) indicate that the adsorption of the methylene blue dye is multilayer type adsorption. For the PHCl sample, neither the Langmuir nor Freundlich model adequately described MB dye adsorption