Determination Of Acid Number Research Articles

Valuation of Ethanol Grade on the Robustness of Acid Number Determination in Fish Oil

The robustness evaluation of the acid number analysis method in fish oil was carried out to see the effect of the type of ethanol used as a solvent in the titration process. The types of ethanol used in this study were pro analysis grade, pharma and food grade, and technical grade. The acid number values (mgKOH/g) in fish oil with various solvents obtained were 2.3955±0.3211 for pro analysis grade; 2.7932±0.2983 for pharma and food grade; 2.7812±0.3362 for technical grade 1; 2.7031±0.3405 for technical grade 2. The acid number for all types of ethanol has a value that is in accordance with the requirements of SNI 8467: 2018 where the acid number value must be less than 3 mgKOH/g. However, if the measurement uncertainty value is included in the calculation, only the pro analysis grade ethanol solvent has an acid number value that is in accordance with the requirements of SNI. The results of the ANOVA test also showed that there was a significant difference in the variation of ethanol types for determining acid numbers because the calculated F value (13.9004) was greater than the F table (3.0984). Therefore, the solvent that must be used in the method of determining acid numbers in fish oil is pro analysis grade ethanol.

Interference of chloride salts in the determination of total acid number in crude oils using catalytic thermometric titration

Crude oils extracted from reservoirs often contain water with corrosion-causing dissolved salts. Therefore, the residual salt content of crude oils supplied to an oil refinery should be as low as possible. The total acid number (TAN) is an indicator of the corrosive activity of crude oil. However, its determination remains an analytical challenge because of the presence of dissolved salts, mineral matter, or chemicals. Herein, we quantified the impact of chloride salts on the measurement of the TAN of titration solvents and crude oil samples using the American Society for Testing and Materials (ASTM) D8045. Water-in-crude oil (W/O) emulsions (2.4 wt% water) were prepared using light and heavy crude oils mixed with saline solutions, and their TAN was evaluated. The precipitates obtained from the titration solvent were characterized. A chloride salt content of 100 mg kg−1 in the titration solvent increased the apparent TAN. Analyses of the precipitates indicated that they comprised Ca(OH)2, Mg(OH)2, and Sr(OH)2. The W/O emulsions of samples 1 (API 31.0) and 2 (API 16.7) exhibited an increase in their TAN of up to 89 and 45 wt%, respectively. When using catalytic thermometric titration, CaCl2, MgCl2, and SrCl2 with concentrations above 100 mg kg−1 interfere with the determination of TAN.

Fully Bio-Based and Solvent-Free Polyester Polyol for Two-Component Polyurethane Coatings

In recent years, many efforts are being devoted to the development of new materials that originate from renewable resources. Polyesters are one of the most important classes of such materials and several bio-based monomers are available for their synthesis. In this work, the development of fully bio-based and solvent-free polyester polyol used for two-component polyurethane coatings on industrial scale is presented. Fossil-based raw materials were substituted with bio-based alternatives that are commercially available on a large scale. Properties of polyols and coatings were determined and measured. Polyols were characterized by the determination of acid number, hydroxyl number, glass transition temperature and refractive index, and measurement of viscosity, color and molecular weight. Coatings were characterized by the determination of mechanical properties, such as hardness, elasticity and impact resistance, and the measurement of optical properties such as gloss, haze, distinctness of image (DOI) and reflected image quality (RIQ) and weathering resistance. Three variations of bio-based polyol were synthesized, then the most suitable version was validated in a clear coat. The results showed that the properties of the bio-based polyol and coating met the requirements and were comparable to the properties of the synthetic counterpart. Results indicate that this newly developed 100% bio-based and solvent-free polyol can be used as a drop-in replacement for synthetic polyol. Furthermore, this work implies that the supply chain is established which allows the green transition in the paint industry.

Robust principal component analysis-multivariate adaptive regression splines (rPCA-MARS) model for determining total acid number (TAN) and total base number (TBN) of crude oil samples using attenuated total reflectance fourier transform infrared (ATR-FTIR) spectroscopy

Rapid assessments of Total Acid Number (TAN) and Total Base Number (TBN) in crude oil samples are significant in the oil industry. The analysis of TAN and TBN was conducted using the standard methods of the American Society for Testing and Materials (ASTM). However, the standard methods are costly and require a large number of samples for analysis. Therefore, providing analytical methods for the rapid crude oil analysis is very essential. In the current research, we report an application of Attenuated Total Reflection Fourier-Transform Infrared (ATR-FTIR) spectroscopy, based on robust Principal Component Analysis-Multivariate Adaptive Regression Splines (rPCA-MARS), for crude oil analysis. In the rPCA-MARS model, the ATR-FTIR spectral matrix data was decomposed into PCs scores using the rPCA method as an input data for the MARS model. The multivariate calibration models were applied to the analysis of crude oil samples based on the quantitative determination of total acid number (TAN) and total base number (TBN). An analytical method was developed for determination of TAN and TBN of crude oil samples. The ATR-FTIR spectroscopy coupled with multivariate calibration methods can be applied as a novel analytical method for crude oil samples. The result of partial least square regression (PLS-R), principle component analysis (PCR), Piecewise-Linear rPCA-MARS and Piecewise-cubic rPCA-MARS models were compared for analysis of total acid and base number of crude oil samples. The squared correlation coefficient (R2) and root mean square error (RMSE) for calibration and prediction sets were calculated to evaluate multivariate calibration models. The importance of methods was studied and discussed. The mean square error (MSE) values of Piecewise-Linear rPCA-MARS for TAN and TBN were 1.587 * 10−4 and 0.009, respectively. The Piecewise-Linear rPCA-MARS model can be successfully applied for the analysis of TAN and TBN of crude oil samples based on the obtained results. The fast and easy prediction capability of the proposed Piecewise-Linear rPCA-MARS model, as compared to standard methods, for determining TAN and TBN without any sample preparation step is important in the oil industry

Determination of carbonyl compounds and ionol in transformer oil by IR spectrometry

Currently, transformer oil is the most widely used liquid dielectric in high-voltage equipment and especially in power transformers. However, in the process of operation oil undergoes gradual aging and physical and chemical properties of oil change resulting in deterioration of insulating properties. Therefore, the main task of preventive diagnostics is to control the quality of the liquid dielectric by some parameters, including tracking changes in the properties of the transformer oil by consumption of the antioxidant additive ionol, as well as by accumulation of oxidized compounds. Compounds of acidic nature (carboxylic acids, esters, aldehydes, ketones, etc.) occupy specific place among the degradation products. A method of simultaneous determination of ionol and carbonyl compounds in oil during its operation in high-voltage transformers is proposed in the present work. The technique is based on infrared spectrometry. Unlike the traditional methods of ionol and acid number determination, the proposed method allows quickly and qualitatively obtain more complete information about the state of liquid dielectric, and, consequently, to take measures for improving its physical, chemical and insulating properties.

Ispitivanje mehaničkih svojstava regranulata PVC-a sa dodatkom plastifikatora iz otpadnog PET-a

The subject of this research is the production process of polyvinyl chloride (PVC) regranulate using a plasticizer synthesized from recycled poly(ethylene terephthalate) (PET). In this way, a plasticizer was synthesized that does not pose a risk to human health and the environment in accordance with the principles of chemical leasing and green chemistry. The obtained plasticizer was characterized using elemental analysis, FTIR, and NMR spectroscopy and determination of hydroxyl and acid number. The mechanical properties of materials obtained on the basis of recycled PVC and plasticizers from PET were tested according to standard methods.

Study of phthalic anhydride and glycerol polycondensation

In the article, the basic physical and chemical properties of polymers based on glyphthalic resin are considered. The main advantages and disadvantages are revealed. The areas of application and the main methods for obtaining glyphthalic resins are considered. The research on studying the course of the polycondensation process on the change of acid number during the reaction of obtaining glyphthalic resin of polyatomic alcohol of glycerol and phthalic acid anhydride is carried out. It is revealed that the results of acid number determination during polycondensation can be used for directed regulation of synthesis of alkyd oligomers and their subsequent curing to obtain a polymer with specified properties. The data was obtained that the polymer under study can be further modified to give special properties that extend the area of its application, as well as to ensure the environmental safety of the waste generated during its use. On the basis of the available data, it is concluded that further research of glyphthalic resin is necessary.

Long term endurance analysis of the effects on ring wear and lubrication oil of biofuel used in a DI diesel engine

In this study, the long-term endurance tests were carried out in an engine that was used 100% diesel and 90% diesel −10% bioethanol blend. The lubricating oil and ring wear were investigated in the direct injection diesel engine using two different fuels under partial load and for 110 h. As a result of long-term endurance tests, ash content, density, viscosity, acid number determination, and flash point values of engine lubricating oil were detected. Moreover, the metal residues (Fe, Al, Cu, Pb, Zn, Mg, Mn, Ni) were signs of wear in the lubricating oil were observed. Samples were taken from the lubricating oil at 55 and 110 h and examined by the Inductively Coupled Plasma-Mass Spectrometer method. Also, tribological and morphological analyses of the replaced piston rings were made for each fuel mixture. The piston rings (first ring, second ring and third ring) had been examined by using the Energy Dispersive X-ray Spectroscopy and Scanning Electron Microscopy. As a result, it was observed that the metal residues in the oil changed over time. Metal residues were showed that after the 55th hour there were more metal residues in the lubricating oil with B10, compared to diesel. While the TAN value of lubricating oil was measured as 3.08 mg KOH/g in the D100 operation, this value was 3.29 mg KOH/g in the B10 operation.

Pengaruh Jenis Alkohol pada Sintesis Alkil Ester dari CPO melalui Reaksi Transesterifikasi Menggunakan Katalis Heterogen CaO-MgO

The purpose of this research is the synthesis of alkyl esters from CPO through transesterification reaction using catalyst CaO-MgO. This experimental laboratory research through stages: (1) CPO refinement, (2) determination of CPO free fatty acid numbers, (3) activation of CaO-MgO catalysts, (5) synthesis of alkyl esters from CPO with alcohol (methanol and ethanol), (6) identification of the components of synthesized alkyl ester using GC-MS,characterization of alkyl esters including density, viscosity, refractive index and acid number test. The results showed that (1) alkyl esters can be synthesized from CPO through the transesterification reaction with methanol and CaO-MgO catalysts with a yield of 85.72%, while the transformation of ethanol is difficult to form ethyl ether (2) the character of methyl ester: density 0.86 g/mL, viscosity 3.23 cSt, refractive index 1.44819, and acid number 0.747 mg KOH/g methyl ester, (3) the main component of the synthesized alkyl ester contains 1.20% methyl myristic compound, methyl palmitate 40.637% methyl linoleate 9.332%, methyl 7-octadecenoate 42.986%, and methyl stearate 4.427%.

Stability of Bituminous Emulsion Induced by Waste Based Bio-Surfactant

In the asphalt industry, bituminous emulsions are widely used in road pavement operations and in building/construction processes such as cold mix asphalt and waterproofing processes, respectively. A very important fact to keep in mind is that not all types of bitumen are suitable for the realization of bituminous emulsions. This is largely due to the variation in their chemical nature and the different cracking processes carried out on the bitumen during the fractional distillation process in the petroleum industry. The objective of this study is to identify the underlying causes of the non-emulsionability of bitumen using Nuclear Magnetic Resonance (NMR) and Dynamic Shear Rheology (DSR) analysis. NMR analysis aims at identifying the fundamental chemical components that are responsible for the emulsionability of the bitumen binder and how important their role is in this phenomenon. On the other hand, the DSR analysis is aimed at determining if the rheological (viscoelastic) behavior of bitumen is implicated in its emulsionability. The indications gotten from the data produced by these techniques, enable us as soon as the analyzed bitumen is deemed non-emulsionable to identify what type of additive can be used to modify the bitumen and alleviate its non-emulsionability until a point where its chemical components become ideal for the realization of bituminous emulsions. In this research work, a model bitumen (labelled as Cimar) which is known for its excellently high emulsionability in the production of anionic bituminous emulsions was used as the reference sample. Two bitumens (labelled as Adriatica and Alma) which from preliminary testing were deemed non-emulsionable were alongside the additives selected and subjected to the aforementioned techniques for analysis on their emulsionability. The NMR data obtained allowed the identification of the chemical nature of the components of the analyzed bitumens and the design of the right additive which improves the bitumen and makes it suitable for the preparation of emulsions. In addition to these, a largely uncommon however effective method of acid number determination of bitumen gave indications on an underlying factor which largely influences the emulsionability of bitumen. An aliphatic and an aromatic surfactant were identified thanks to the spectroscopic findings in this study.

The Use of Ethanol as an Alternative Solvent to Replace 2-Propanol in the Determination of Total Acid Number in Lubricant by Potentiometric Titration

In determining the quality of lubricant, acid content affects the quality of the lubricant. The acid content in the lubricant can be determined by using ASTM D664 Standard Method to determine Total Acid Number. The purposes of this research are to obtain the optimum ratio of a solvent mixture of Toluene and Ethanol to determine the Total Acid Number using the Potentiometric titration method and set the value of its accuracy and precision. This research aims to compare the value of the total acid number of the modified method to the standard method (ASTM D664). The modified method in this research uses toluene and ethanol, with ratios 70 percent: 30 percent. Kolmogorov Smirnov normality test shows that both methods produce normal data, and based on the t-test result, it is showed that both methods produce the results that are not significantly different. Based on the measurement of accuracy and precision, the method generates accurate and precise data. From the overall result, it can be concluded that the solvent mixture of Toluene and Ethanol with ratios 70 percent: 30 percent, can be used as an alternative solvent mixture to replace the solvent mixture in ASTM D664 Standard Method.

Вплив біологічно активних сполук на стабільність жирового комплексу м’яса птиці механічного обвалювання під час зберігання

Goal. To study the influence of biologically active compounds on the process of lipid oxidation of the fat complex in poultry meat of mechanical rolling (PMMR) during storage. Methods. Research of acid and peroxide numbers of model samples of PMMR was carried out by employees of the department of technology of meat products according to GOST 314702012 «Poultry meat, by-products, and semi-finished products from poultry meat. Methods of organoleptic and physicochemical research». The method of determining the thiobarbituric number is based on the formation of colored substances as a result of the interaction of fat oxidation products with 2-thiobarbituric acid and on the measurement of the color intensity on the spectrophotometer. The object of research was PMMR with the addition of the following biologically active compounds: water and fat green tea extract, water and fat rosemary extract, dihydroquercetin. Results. The influence of biologically active compounds on the oxidizing properties of the PMMR fat complex was studied. The results of the determination of acid and peroxide numbers during the storage of the studied model samples and control for 120 days indicated the effectiveness of the selected antioxidants. As antioxidants they used natural extracts in the following quantities: fat-soluble rosemary — 0.1%; water-soluble rosemary — 0.07%; fat-soluble and water-soluble green tea — 0.05%; dihydroquercetin — 0.025%. It was found out that these compounds inhibit oxidative processes in 3.7 – 5.2 times. Conclusions. The obtained research results testify to the expediency of using biologically active compounds to reduce oxidative damage in PMMR during storage.

Proximate Characteristics and Nutritional Value of White Anchovy Flour

Low fish consumption in some parts of Indonesia is caused by the high price of several types of fish. Its include types of fish that have a low social value in the community so it is less desirable although their value of nutrients is very good. Anchovy is actually the best source of calcium and protein. Calcium in white anchovy (Stolephorus sp) is very stable resistant and not easily soluble in water. White anchovies (Stolephorus sp) are excellent as a source of calcium and protein in children who are in their infancy, expectant mothers, nursing mothers and adult women to prevent osteoporosis. When the production volume of white anchovy (Stolephorus sp) is increased, making fish flour is a preservation method, It will make the benefits of anchovy can be maximised. White anchovy flour quality can be measured by proximate characteristics and nutritional quality. Proximate parameters in this study are determination of water content, ash content, peroxide numbers, acid numbers, and saponification numbers. Nutritional quality analysis such as carbohydrates, protein, fat, calcium, iron, fiber, zinc, DHA, EPA and trans fat. The characteristics of the proximate are good and meet the quality standards of a food product from fresh anchovy (Stolephorus sp) such as fiber content, ash content, number of peroxide and trans fatty acids. The best nutritional quality of fresh anchovy (Stolephorus sp) are the content of protein, calcium, iron ,zinc, DHA and EPA.

Synthesis and characterization of ricinoleic acid based hyperbranched alkyds for coating application

Hyperbranched alkyds based on ditrimethylolpropane, dimethylolpropionic acid, and ricinoleic acid were synthesized. The synthesized resins were characterized by the determination of hydroxyl and acid numbers, viscosity, average molecular masses, and molecular masses distribution. Compared with conventional alkyd resins of similar molar masses, the synthesized hyperbranched alkyds have significantly lower viscosity values at a given temperature. Therefore, a significantly smaller amount of organic solvents is required for their dissolution and can be used as precursors to obtain eco-friendly coatings. The obtained hyperbranched alkyd resins were cured by two commercial melamine resins (mass ratio 70:30). The curing of the resin mixtures was examined by FTIR spectroscopy, rheometry, and by the determination of gel content. The curing of the resin mixtures proceeds via the reactions between hydroxyl and carboxyl groups of hyperbranched alkyds with isobutoxymethyl and methoxymethyl groups in melamine resins. Hyperbranched alkyd/melamine resin mixtures were cured at 150 °C for 60 min. Thermal properties, dynamic mechanical behavior, physico-mechanical characteristics, and chemical resistance of cured films were determined. The crosslinking densities of films obtained from mixtures using hexamethoxymethyl melamine resin are significantly higher than those based on mixtures using isobutylated melamine resin. The thermal degradation of cured films is a complex process, and their thermal stability increases slightly with the increase of hyperbranched alkyds generation. It is assumed that mixtures of synthesized hyperbranched alkyds with melamine resins would be suitable for obtaining the coatings with good chemical resistance and physical-mechanical properties.

KARAKTERISASI VIRGIN COCONUT OIL (VCO) REMPAH

ABSTRACT Gugule, S. and F. Fatimah. 2010. Characterization of spices virgin coconut oil A study has been carried out to find out the effect of some spices type on quality and characteristic of fatty acid of virgin coconut oil (VCO). The test of spice VCO quality conducted with the determination of iodine and acid number, water content and peroxide number. The profile of fatty acid of VCO was tested with the liquid gas chromatography, using the internal standard of margaric acid. The experimental result showed that control and spice VCO that is VCO nutmeg, leaf of salam, sweet basil and galingale have the quality fulfilling standard APCC, except number iodine. As compared to control, the addition of spice at making VCO nor have an effect to fatty acid percentage in VCO, but having an effect to reduction fatty acid content in VCO (calculated in mg / 100g sample).. Kata kunci : Characterization, virgin coconut oil, spices

Evaluation of Potentiometric Methods for Acid Number Determination in Commercial Biodiesel Samples and Proposal of Alternative Method

The acid number (AN) is an important parameter that informs the quantity of free fatty acids (FFA) and acids originating from degradation reactions of biodiesel during production process and its storage. Due to the need to research and evaluate new environmentally friendly methods that reduce the toxic use solvents and minimize amounts of sample without significant loss of precision in the AN measurements by ASTM D664 method, the aims of this work were: i) to establish a procedure of cleaning and hydration of glass electrode to perform AN analyzes according ASTM D664 method in two commercial B100 biodiesel samples produced at Brazilian central-west region; ii) to propose the modification of the ASTM D664 method by reducing the amount solvent mixture and the sample size and to compare AN values obtained for cited samples with those obtained by ASTM D664 and EN 14104 methods. We proposed a simple procedure of cleaning and hydration of electrode. In this procedure, after each titration of the sample, electrode is rinsed with small portion of ethanol (approximately 5 mL) and then the electrode is immersed in distilled water by 15 min. The method proposed in this work is a modification ASTM D664 method, reducing by half the amount of sample and using only 50 ml solvent mixture against 125 for the official method. The acid number values determined indicate that biodiesel samples are in agreement with the maximum value stipulated by ANP resolution. By statistical analysis with confidence level of 95%, the results obtained with the proposed method are significantly equivalent to the official method ASTM D664, presenting satisfactory results, since the modification reduced the amount of solvent mixture by 60% and the sample amount by 50% used in the analysis, contributing to environmentally friendly analyzes and favoring both sustainable development and economic issues linked to biofuel research. DOI: http://dx.doi.org/10.17807/orbital.v10i1.1034

Sulfur and Total Carboxylic Acid Number Determination in Vacuum Gas Oil by Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy

Sulfur removal is one of the key functions of vacuum gas oil (VGO) hydrotreating reactors. Knowing feed and product properties real-time or near-real-time improves reactor operations. The VGO section of crude distillation unit is also prone to severe high-temperature sulfidic and naphthenic acid corrosion. In this article, we evaluate a single-reflectance attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy as a possible quick and cost-effective methodology to determine total carboxylic acid number (TCAN) and total sulfur content of VGO. The study shows that single-reflectance diamond ATR crystal methodology has the right signal-to-noise ratio to accurately predict TCAN and total sulfur within the primary method’s repeatability. Statistical models have been developed using 64 sample sets of vacuum gas oil and out of which 10 samples were used for the cross-validation of the model. The range of TCAN in VGO samples used in this study was between 0.37 and 13.8 mg KOH/g, and sulfur ...

Hydroperoxides Formation in Jet Fuels Coming from Different Production Processes in Simulated Fuel System of Modern Aircraft

Abstract The paper presents issues related to the process of thermal degradation of jet fuel. This process is of a different nature depending on temperature and time, in which the fuel is subjected to thermal action. The standard method for testing the jet fuel thermal stability seems to be insufficient, therefore, the conduct of the research on a dedicated test rig was taken in this paper. The assessment of the fuel degradation process was carried out on the basis of determination of hydroperoxide and acid numbers as signs of the occurred process. The article has been prepared within the research project No. 2011/01/D/ST8/06567 funded by the National Science Centre in Poland.

A rapid method for the quantitative analysis of total acid number in biodiesel based on headspace GC technique

The purpose of this work is to introduce a rapid and practical method for quantitatively analyzing total acid number in biodiesel by a reaction headspace gas chromatography. In this method, the carbon dioxide formed by the reaction of acidic species (i.e., fatty acids) in biodiesel and sodium bicarbonate can be measured by GC. The results showed that the complete reaction can be achieved in 25min at 75°C. The relative standard deviation of this method in total acid number determination was within 2.93%, the relative differences has been determined by comparing the total acid number obtained from this new analytical technique with the data from the reference technique (i.e., potentiometric titration), which are less than 8.05%. The reaction HS-GC technique is automated, efficient and can be a reliable tool for quantifying the total acid number in biodiesel and related research.

OPTIMASI SINTESIS BIOSURFAKTAN KARBOHIDRAT ESTER DARI ASAM PALMITAT DAN FRUKTOSA MENGGUNAKAN ENZIM LIPASE TERIMOBILISASI


 Carbohydrate ester is one of many needed nonionic surfactant groups and has the potential to be an environmental friendly surfactant. The principal problem in the synthesis of carbohydrate ester is to obtain the optimum conversion of palmitic acid from temperature influence, the amount of biocatalyst and reaction time. The optimization of carbohydrate ester synthesis is carried out on three variables that influence the esterification reaction. Therefore, the esterification process is carried out by reacting directly the palmitic acid and fructose using a Novozyme®435 an immobilized lipase enzyme catalyst with a free variable of reaction temperature of 41,5 oC, 45 oC, 50 oC, 55 oC, 58,4 oC, the amount of biocatalyst is 6,63%, 8%, 10%, 12%, 13,36% mass based palmitic acid also reaction time of 7,6 hours; 24 hours; 48 hours; 72 hours; 88,3 hours and reacted with fixed variable in 500 rpm; 3:1 substrate ratio (fructose:palmitic acid) and solvent amount 10 ml. The mixture is then separated from the catalyst by filtration. The product was analyzed with determination of acid number to obtain conversion percent of fructose ester, determination of Hydrophilic Lipophilic Balance, Fourier Transform Infrared (FTIR) an surface tension determination. The optimum conversion rate obtained is 61,80% at 55 oC of reaction temperature, Novozyme®435 enzyme count is 12% and 72 hours of reaction time. From the result of fructose ester surfactant analysis obtained HLB 10,592 value which showed fructose ester surfactant can be used as emulsifier of oil in water.