scholarly journals Refining Vegetable Oils: Chemical and Physical Refining

2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Said Gharby

This review presents recent technologies involved in vegetable oil refining as well as quality attributes of crude oils obtained by mechanical and solvent extraction. Usually, apart from virgin oils, crude oils cannot be consumed directly or incorporated into various food applications without technological treatments (refining). Indeed, crude oils like soybean, rapeseed, palm, corn, and sunflower oils must be purified or refined before consumption. The objective of such treatments (chemical and physical refining) is to get a better quality, a more acceptable aspect (limpidity), a lighter odor and color, longer stability, and good safety through the elimination of pollutants while minimizing oil loss during processing. However, the problem is that refining removes some essential nutrients and often generates other undesirable compounds such as 3-MCPD-esters and trans-fatty acids. These compounds directly influence the safety level of refined oil. Advantages and drawbacks of both chemical and physical refining were discussed in the light of recent literature. Physical refining has several advantages over chemical one.

2016 ◽  
Vol 211 ◽  
pp. 124-129 ◽  
Author(s):  
Jan Šmidrkal ◽  
Markéta Tesařová ◽  
Iveta Hrádková ◽  
Markéta Berčíková ◽  
Aneta Adamčíková ◽  
...  

2018 ◽  
Vol 5 (1) ◽  
pp. 43-54
Author(s):  
Suresh Aluvihara ◽  
Jagath K Premachandra

Corrosion is a severe matter regarding the most of metal using industries such as the crude oil refining. The formation of the oxides, sulfides or hydroxides on the surface of metal due to the chemical reaction between metals and surrounding is the corrosion that  highly depended on the corrosive properties of crude oil as well as the chemical composition of ferrous metals since it was expected to investigate the effect of Murban and Das blend crude oils on the rate of corrosion of seven different ferrous metals which are used in the crude oil refining industry and investigate the change in hardness of metals. The sulfur content, acidity and salt content of each crude oil were determined. A series of similar pieces of seven different types of ferrous metals were immersed in each crude oil separately and their rates of corrosion were determined by using their relative weight loss after 15, 30 and 45 days. The corroded metal surfaces were observed under the microscope. The hardness of each metal piece was tested before the immersion in crude oil and after the corrosion with the aid of Vicker’s hardness tester. The metallic concentrations of each crude oil sample were tested using atomic absorption spectroscopy (AAS). The Das blend crude oil contained higher sulfur content and acidity than Murban crude oil. Carbon steel metal pieces showed the highest corrosion rates whereas the stainless steel metal pieces showed the least corrosion rates in both crude oils since that found significant Fe and Cu concentrations from some of crude oil samples. The mild steel and the Monel showed relatively intermediate corrosion rates compared to the other types of ferrous metal pieces in both crude oils. There was a slight decrease in the initial hardness of all the ferrous metal pieces due to corrosion.


2021 ◽  
Vol 2 (1) ◽  
pp. 74-91
Author(s):  
Beatrice Casali ◽  
Elisabetta Brenna ◽  
Fabio Parmeggiani ◽  
Davide Tessaro ◽  
Francesca Tentori

The review will discuss the methods that have been optimized so far for the enzymatic hydrolysis of soapstock into enriched mixtures of free fatty acids, in order to offer a sustainable alternative to the procedure which is currently employed at the industrial level for converting soapstock into the by-product known as acid oil (or olein, i.e., free fatty acids removed from raw vegetable oil, dissolved in residual triglycerides). The further biocatalyzed manipulation of soapstock or of the corresponding acid oil for the production of biodiesel and fine chemicals (surfactants, plasticizers, and additives) will be described, with specific attention given to processes performed in continuous flow mode. The valorization of soapstock as carbon source in industrial lipase production will be also considered.


Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2766 ◽  
Author(s):  
Jandyson Santos ◽  
Alberto Wisniewski Jr. ◽  
Marcos Eberlin ◽  
Wolfgang Schrader

Different ionization techniques based on different principles have been applied for the direct mass spectrometric (MS) analysis of crude oils providing composition profiles. Such profiles have been used to infer a number of crude oil properties. We have tested the ability of two major atmospheric pressure ionization techniques, electrospray ionization (ESI(±)) and atmospheric pressure photoionization (APPI(+)), in conjunction with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The ultrahigh resolution and accuracy measurements of FT-ICR MS allow for the correlation of mass spectrometric (MS) data with crude oil American Petroleum Institute (API) gravities, which is a major quality parameter used to guide crude oil refining, and represents a value of the density of a crude oil. The double bond equivalent (DBE) distribution as a function of the classes of constituents, as well as the carbon numbers as measured by the carbon number distributions, were examined to correlate the API gravities of heavy, medium, and light crude oils with molecular FT-ICR MS data. An aromaticity tendency was found to directly correlate the FT-ICR MS data with API gravities, regardless of the ionization technique used. This means that an analysis on the molecular level can explain the differences between a heavy and a light crude oil on the basis of the aromaticity of the compounds in different classes. This tendency of FT-ICR MS with all three techniques, namely, ESI(+), ESI(−), and APPI(+), indicates that the molecular composition of the constituents of crude oils is directly associated with API gravity.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Yu Hua Wong ◽  
Kok Ming Goh ◽  
Kar Lin Nyam ◽  
Ling Zhi Cheong ◽  
Yong Wang ◽  
...  

Abstract 3-Monochloropropane-1,2-diol (3-MCPD) esters and glycidyl esters (GE) are heat-induced contaminants which form during oil refining process, particularly at the high temperature deodorization stage. It is worth to investigate the content of 3-MCPD and GE in fries which also involved high temperature. The content of 3-MCPD esters and GE were monitored in fries. The factors that been chosen were temperature and duration of frying, and different concentration of salt (NaCl). The results in our study showed that the effect was in the order of concentration of sodium chloride < frying duration < frying temperature. The content of 3-MCPD esters was significantly increased whereas GE was significantly decreased, when prolong the frying duration. A high temperature results in a high 3-MCPD ester level but a low GE level in fries. The present of salt had contributed significant influence to the generation of 3-MCPD. The soaking of potato chips in salt showed no significant effect on the level of GE during the frying. The oil oxidation tests showed that all the fries were below the safety limit. Hence, the frying cycle, temperature and the added salt to carbohydrate-based food during frying should be monitored.


Author(s):  
Guoxi He ◽  
Yongtu Liang ◽  
Limin Fang ◽  
Qi Zheng ◽  
Liying Sun

The disconnect between the optimization systems of upstream production and downstream demand poses a legitimate problem for China’s refined oil industry in terms of overproduction waste. Established methods only partially model the refinery system and are unable to integrate detailed production plans or meet market demands. Therefore, the research on production scheduling optimization combined with the demand of downstream pipeline network has very real applications that not only reduce the consumption of human/material resources, but also increase economic efficiency. This paper aims to optimize the production scheduling of refined oil transportation based on the demand of downstream product pipelines by analyzing the relationships between crude oil supply, refinery facility capacities and refinery tanks storage. The new model will minimize the refined production surplus therefore minimizing refinery costs and wastage. This is done by implementing models custom designed to optimize the three subsystems of the overall process: oil product blending scheduling optimization, producing and processing equipment scheduling optimization, and mixed crude oil scheduling optimization. We first analyzed the relationship between all the production units from the crude oil to the distributional destinations of oil products. A mathematical model of the refinery production scheduling was then built with minimum total surplus inventory as the objective function. We assumed a known downstream demand and used a step by step model to optimize oil stocks. The oil blending plan, production scheduling, amount of crude oil, and refined oil mixing ratios were all derived from the model using three methods: a nonlinear method called Particle Swarm Optimization (PSO), the simplex method and the enumeration method. The evidence laid out in this paper verifies our models functionality and suggests that systems can be significantly optimized by using these methods which can provide solutions for industries with similar challenges. Optimization of the refinery’s overall production process is achieved by implementing models for each of the three distinguished subsystems: oil blending model, plant scheduling model, and the mixed crude oil refining model. The demand dictates the final production quantities. From those figures we are able to place constraining limits on the input crude oil. The refined oil production scheme is continuously enhanced by determining the amount of constituent feed on the production equipment according to the results of previous production cycle. After optimization, the minimum surplus inventory of the five oil components approach their lower limits that were calculated using our models. We compare the literature on scheduling optimization challenges both in China and abroad while providing a detailed discussion of the present situation of Chinese refineries. The interrelationships of production processes on each other are revealed by analyzing the system and breaking it down to three fundamental parts. Basing the final production predictions on the downstream demand, we are able to achieve a minimum refinery surplus inventory by utilizing a comprehensive refinery scheduling model composed of three sub-models.


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