A kinetic study of esterification of naphthenic acids from a Colombian Heavy Crude Oil

This article presents the kinetic study of the esterification reaction of naphthenic acids from a Colombian heavy crude oil, with a Total Acid Number (TAN) of 7,33 mgKOH/g, in a batch type reactor. Temperature was changed between 150 - 250°C while the ratio moles of methanol per mole of carboxylic groups, remained constant in 20:1. The reaction time was varied from 0 - 600 minutes. Reduction in the concentration of naphthenic acids in the reactor is determined by the measurement of Number Total Acid (TAN), ASTM D 664. Naphthenic acids were extracted from the crude and structurally characterized by Fourier Transform Infrared Spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). The esterified oil was analyzed by FTIR, to identify the variation of the main functional groups. After determining the activation energy, frequency factor and, reaction order, a kinetic law was proposed for the esterification of naphthenic acids in Colombian heavy oil. Finally, it was evaluated the effect of esterification of naphthenic acids on the corrosion of steel ASTM A106 Gr.B. The corrosion of steel was reduced from 34,16 to 3,08 mils per year, (mpy), after esterification of naphthenic acids.

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Enhancing Rheological Properties and Reduction of Total Acid Number of a Heavy Crude Oil Using Ethanol and Trona

10.2118/205621-ms ◽

2021 ◽

Author(s):

Ahmed Almadhaji ◽

Mohammed Saeed ◽

Hitham Ibrahim ◽

Anas Ahmed ◽

Ragaei Maher

Keyword(s):

Crude Oil ◽

Rheological Properties ◽

Kinematic Viscosity ◽

Acid Number ◽

Capillary Viscometer ◽

Heavy Crude Oil ◽

Production Operation ◽

Total Acid ◽

Total Acid Number ◽

Heavy Crude

Abstract One of Sudanese fields has a heavy crude oil which has a high Total Acid Number (TAN) and high viscosity, can cause a lot of problems in production operation, transport, and storage facilities. The effect of ethanol dilution on the rheological properties of crude (especially the kinematic viscosity) was studied and presented. Moreover, the consequence of blending Trona (NaHCO3.Na2CO3) with a specified amount of Ethanol in the crude can reduce (TAN) to acceptable limits for solving corrosion and flowability problems. The approach is based on the experiments and laboratory works on the crude's samples after blending with a certain amount of Trona and Ethanol. It depends on the results of apparatuses, that are used to measure the samples, for instance, Calibrated glass capillary viscometer and ASTM D664 titration volume Total Acid Number tester which are employed to get the values of kinematic viscosity and TAN, respectively. The tests are established with crude have kinematic viscosity (187 cst) at temperature 75°C and TAN almost (8.51). While increasing the dosage of Trona at the ambient temperature (38°C) with the certain mass percentage of Ethanol (5%), TAN is decreased from (8.51 to 4.00 mgKOH/g). Also, the kinematic viscosity is declined from (187 cst to 96.75 cst) after increasing the volume of Ethanol at 75°C. These outcomes indicated that Ethanol could reduce Sudanese heavy crude's viscosity, and the Trona could decrease the TAN. This reduction occurred due to Ethanol dilution. The Ethanol molecules disturb the molecular structure of the crude, which forms polar bond within the hydrocarbon chain that leads to lower the friction between molecules of hydrocarbon in the crude. Also, Trona shrinks TAN because the Hydroxide ions (OH+) that founded in Trona neutralize the Hydrogen ions (H−) in Naphthenic acid in Sudanese heavy crude. This study can be summarized in the ability to solve the difficulty of transporting and processing the heavy crude oil in refineries; maintains the quality of the crude while utilizing it with friendly environmental materials and low cost.

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Kinetic study of thermal and catalytic pyrolysis of Brazilian heavy crude oil over mesoporous Al-MCM-41 materials

Journal of Thermal Analysis and Calorimetry ◽

10.1007/s10973-015-4408-4 ◽

2015 ◽

Vol 119 (3) ◽

pp. 2151-2157 ◽

Cited By ~ 11

Author(s):

Ana C. F. Coriolano ◽

Aline A. A. Oliveira ◽

Rafaely A. F. Bandeira ◽

Valter J. Fernandes ◽

Antonio S. Araujo

Keyword(s):

Crude Oil ◽

Kinetic Study ◽

Catalytic Pyrolysis ◽

Heavy Crude Oil ◽

Heavy Crude ◽

Mcm 41

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Basic ionic liquids with imidazole anion: New reagents to remove naphthenic acids from crude oil with high total acid number

Fuel ◽

10.1016/j.fuel.2012.04.014 ◽

2012 ◽

Vol 99 ◽

pp. 83-87 ◽

Cited By ~ 33

Author(s):

Yu Sun ◽

Li Shi

Keyword(s):

Ionic Liquids ◽

Crude Oil ◽

Naphthenic Acids ◽

Acid Number ◽

Total Acid ◽

Total Acid Number

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EXTRACTION OF NAPHTHENIC ACIDS FROM ACIDIC PETROLEUM CRUDE OIL UTILIZING 2-METHYLIMIDAZOLE WITH THE AID OF Ca/Al2O3 AND Ce/Al2O3 CATALYSTS

e-Academia Journal ◽

10.24191/e-aj.v7isi-temic18.5396 ◽

2019 ◽

Vol 7 (SI-TeMIC18) ◽

Cited By ~ 1

Author(s):

Norshahidatul Akmar Shohaimi ◽

Wan Azelee Wan Abu Bakar ◽

Nurasmat Mohd Shukri ◽

Khairan Shaidi

Keyword(s):

Crude Oil ◽

Reaction Times ◽

Naphthenic Acids ◽

Acid Number ◽

Catalyst Loading ◽

Total Acid ◽

Characterization Methods ◽

Oil Refineries ◽

Total Acid Number ◽

Al2o3 Catalyst

Naphthenic acids (NAs) is one of the major sources of corrosion in oil pipelines and distillation units in crude oil refineries. Removing NA compounds from crude oils is regarded as one of the most crucial processes in heavy oil upgrading. Catalytic deacidification method had been developed in order to reduce the total acid number values in crude oil. Crude oil from Petronas Penapisan Melaka had been chosen to be studied with original total acid number (TAN) of 2.43 mg KOH/g. The parameters used were different catalyst calcination temperatures, catalyst loading, reagent concentration, reaction times and reaction temperature. Acid removal agent of 2-methylimidazole in ethanol and monometallic calcium and cerium doped with alumina were used as a catalyst. The results showed that with the aid of catalyst, the TAN can be reduced to lower than 1 mg KOH/g. Catalyst of Ca/Al2O3 calcined at 900oC gave a better reduction than Ce/Al2O3 with 83.54% of TAN reduction (2.43 to 0.4) for Ca/Al2O3 catalyst and 71.19% (2.43 to 0.7) for Ce/Al2O3 catalyst. The best catalyst underwent several characterization methods such as X-Ray Diffraction Spectroscopy (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetry Analysis (TGA-DTA) for its physicochemical properties. It can be concluded that catalytic deacidification method was effective in extracting NAs from the crude oil thus lowered the TAN value to less than 1 mg KOH/g. Keywords: Naphthenic acids; Crude oil; Catalysts

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Continuous desalting concept on ionic liquid-mediated de-acidification process of crude oil: A pilot study

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1195/1/012013 ◽

2021 ◽

Vol 1195 (1) ◽

pp. 012013

Author(s):

A Hussain ◽

J Basar

Keyword(s):

Ionic Liquid ◽

Crude Oil ◽

Naphthenic Acid ◽

Naphthenic Acids ◽

Acid Number ◽

Single Stage ◽

Wash Water ◽

Total Acid ◽

Oil Emulsion ◽

Carry Over

Abstract Desalting process concept was tested using methyltrimethylammonium methylcarbonate [N4441][MeCO3] treated Pyrenees crude oil (initial Total Acid Number (TAN) of 1.6 mg KOH/g oil) with the aim to gain empirical evidences on the effectiveness of in-line water washing and electrostatic aided phase separation as mean to recover the naphthenic acid derivatives for recycling. The treated crude oil (final TAN value of less than 0.3 mg KOH/g oil) was subjected to typical operating scheme such as single stage desalting and effects of water wash volumes. The novelty of the work comes from the utilisation of ionic liquids to neutralise acid components of the crude oil. Furthermore, the work is also able to test the hypothesis of whether naphthenate salts behave as is its inorganic counterpart and quantify the solubility behaviour in water as extraction medium. The effectiveness of such scheme will be measured against naphthenic acids derivative percent recovery in the wash water. The results indicate the electrostatic conditions can facilitate the recovery of the naphthenate salts post neutralization with high recovery rate of average of 70.6 % with 30 % water wash volume in a single-stage contact, observed over 12 hours steady-state operation. The water wash weight was observed to increase post separation which indicate hydrocarbon carry-over in the heavy phase due to formation of tight water – oil emulsion. The technique is viable should the amount of water required is available and the process water can be recycled safely into the desalter again without causing tripping to the desalter. Ionic liquid can be used in conjunction with desalter and the presence of electrostatic field did hasten the separation of the phases, however the amount of water used may hinder the viability of the solution.

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The Effectiveness of Ni/Ce/Al2O3 Catalyst in the Extraction of Naphthenic Acids from Acidic Crude Oil

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1025.284 ◽

2021 ◽

Vol 1025 ◽

pp. 284-289

Author(s):

Nurul Hidayah Aziz ◽

Norshahidatul Akmar Mohd Shohaimi ◽

Noraini Safar Che Harun

Keyword(s):

Crude Oil ◽

Catalyst Support ◽

Xrd Analysis ◽

Pure Metal ◽

Naphthenic Acids ◽

Acid Number ◽

Oil Refinery ◽

Catalyst Loading ◽

Incipient Wetness Impregnation ◽

Total Acid

Processing of petroleum crude oil with high total acid number (TAN) lead to corrosion problems in oil refinery equipment, storage, facilities and even reduces the performances of the oil. The purpose of this study is to overcome the corrosion problem in oil refinery by reducing the TAN in the oil to less than 1 mgKOH/g. A 2-methylimidazole in ethanol with the aid of Ni/Ce (10:90)/Al2O3 catalyst through the catalytic deacidification technique. The catalyst was prepared by using Incipient Wetness Impregnation (IWI) methods on alumina beads as catalyst support and calcined at 800°C, 900°C and 1000°C. Ni/Ce (10:90)/Al2O3 catalyst was characterized by using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction Spectroscopy (XRD) and Brunauer-Emmett-Teller (BET) to study physicochemical properties of the catalyst. The results shows that Ni/Ce (10:90)/Al2O3 catalyst successfully reduced TAN in crude oil to 0.50 from 4.22 mg KOH/g at 1000°C calcination temperature and catalyst loading of 0.39% (7 beads). XRD analysis proposed Al2O3 and CeO2 fcc was the active site for Ni/Ce (10:90)/Al2O3 catalyst. C-H alkanes stretching, -CH2- alkanes stretching and pure metal oxides stretching modes were detected on the catalyst at wavelength of 2952.49 to 2852.82, 1599.38, and 862.81 to 537.27 cm-1 respectively by FTIR analysis after catalytic deacidification process which indicates that there were impurities that have adsorbed on the catalyst surface. As a conclusion, the catalysts successfully reduced the TAN value of acidic crude oil to less than 1.00 mg KOH/g.

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