Journal of Molecular Liquids 222 (2016) 680–690

Contents lists available at ScienceDirect

Journal of Molecular Liquids

journal homepage: www.elsevier.com/locate/molliq

Dipoles poly(ionic liquids) based on 2-acrylamido-2-methylpropane sulfonic acid-co-hydroxyethyl methacrylate for demulsification of crude oil water emulsions

Ayman M. Atta a,b,⁎, Hamad A. Al-Lohedan a,MahmoodM.S.Abdullaha a Surfactants Research Chair, Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia b 2 Petroleum Application Department, Egyptian Petroleum Research Institute, Cairo 11727, Egypt article info abstract

Article history: New mechanism for demulsification of crude oil water emulsion was elucidated to apply poly(ionic liquids), PILs, Received 24 March 2016 as demulsifier. New PILs were prepared from quaternized ethoxylate octadecylamine acrylamido-2- Received in revised form 23 July 2016 methylpropane sulfonate (AMPS-EOA) followed by radical copolymerization with 2-hydroxyethyl methacrylate Accepted 25 July 2016 copolymers. The hydroxyl group of HEMA was esterified with bromoacetyl chloride followed by reaction with Available online 26 July 2016 triphenyl phosphine to obtain polymerizable ionic liquid (HEMAP). AMPS-EOA was copolymerized with HEMAP to produce new dipoles PIL. The demulsification mechanism of petroleum crude oil water emulsions in Keywords: Poly(ionic liquid) the presence and absence of the prepared PILs was elucidated using single drop technique. The prepared PILs Demulsifier based on AMPS-EOA/HEMAP copolymer showed greater demulsification for petroleum emulsions. The data Quaternization were confirmed by optical microscope and average particle size distribution for crude oil emulsions. Single drop method © 2016 Published by Elsevier B.V. Demulsification mechanism

1. Introduction demulsifiers because they are environmentally friendly nontoxic mate- rials due to their low vapor pressure, high thermal stability and high Chemical demulsification of stable crude oil is the most widely used conductivity [11–15]. The PILs were used as demulsifiers for W/O emul- method among thermal, electrical, chemical, acoustic, flotation, ultra- sions using microwave or irradiation [11,13] to increase the dehydra- sonic wave treatment biological demulsification, filtration, electrostatic tion rate of emulsions instead of conventional heating procedures. separation and mechanical treatment to separate the emulsified crude Therefore, the design of an single efficient emulsion breaker polymers oil with water [1–4]. Although these techniques have several advan- based on PILs to replace the surfactant blends is obviously a complex tages, they cannot completely meet the requirements of down- stream challenge that required a lot of researches in this field. To address this industries. Thousands of chemical surfactants have been prepared and challenge, the mechanism used to explain the destabilizing of crude mixed together to produce many effective demulsifiers for different oil water emulsion and the role of PILs chemical structure should be types of crude oil water emulsions [5]. Several types of polymeric sur- well understood. The mechanism of dehydration of crude oil water factants having different chemical structures as linear, comb, branched emulsions using PIL was not addressed previously elsewhere. and dendrites polymers were used to design highly effective chemical There are different types of PILs are available on the market and demulsifiers using inorganic magnetite and titania nanomaterials [6– there are some PILs still only for laboratory use [16,17]. The available 10]. The effective chemical demulsifiers were formulated by using PILs derivatives based on organic salts of quaternary hydrophobic three different chemical components as breaking, coalescing, and clari- amines, imidazolium and pyridinium organic salts [18–22] were applied fying agents to achieve high demulsification efficiency in the short time. in petroleum field as asphaltene dispersants [19], agents for upgrading Moreover, the demulsification mechanism of chemical demulsifiers is heavy oil through the separation of asphaltenes [20] and for enhanced quite complicated. It was reported that there is no any demulsifier can oil recovery of crude oil applications [21,22]. The reactivity of PILs mol- be used to demulsify all kinds of crude oil emulsions [4].Itisnecessary ecules can be enhanced by preparing amphiphilic PILs that contained to explore new chemical to demulsify crude oil water emulsions due to reactive hydrophobic and hydrophilic moieties [23]. From this point of environmental requirements and to achieve the highest possible effi- view, it can be considered that the chemical structure and balance be- ciency. Recently, poly (ionic liquid)s, PILs, were used as effective tween hydrophilic and hydrophobic moieties of PILs play an important role in the demulsification process. Moreover, the principal roles of the surfactants in destabilization of emulsion have been studied [24]. ⁎ Corresponding author at: Surfactants Research Chair, Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia. The mechanism was focused on the reduction of interfacial tension E-mail address: [email protected] (A.M. Atta). and interfacial viscosity at water/oil interfaces rather than the oil film

http://dx.doi.org/10.1016/j.molliq.2016.07.114 0167-7322/© 2016 Published by Elsevier B.V. A.M. Atta et al. / Journal of Molecular Liquids 222 (2016) 680–690 681 rupture rate. In this work, new PILs based on phosphonium and ammo- vacuum rotary evaporator for 24 h to obtain viscous transparent nium cations of 2-acrylamido-2-methylpropane sulfonic acid-co- amber oils. The quaternized AMPS/HEMA was designated as AMPS- hydroxyethyl methacrylate (AMPS-co-HEMA) were prepared to apply EOA/HEMA. The yield % of AMPS-EOA/HEMA was 99.2%. as demulsifier of a water-in-oil and oil-in-water emulsions at 60 °C. The mechanism of demulsification of crude oil water emulsion using PILs was proved by focusing on oil film drainage time, half-life time 2.3. b-Preparation of AMPS-EOA/AMPSP and film rupture constant between oil and water in the presence of PILs. Moreover, the relation between the chemical structure of PILs HEMA (0.05 mol; 6.507 g) was dissolved in 40 mL of THF and 5 mL of and their demulsification efficiencies for crude oil emulsions can be triethylamine and keep in the ice bath at 0 °C. BAC (0.05 mol; 7.8695 g) also investigated in the present work. dissolved in 10 mL of THF was added dropwise to the reaction temper- ature. The reaction mixture was mixed and the temperature of reaction 2. Experimental was kept at 10 °C for 1 h. The precipitate of triethylamine hydrochloride was removed by filtration. The filtrate was purified under pressure 2.1. Materials using rotary evaporator to produce bromoacetyl ethanoate methacry- late (BEMA) as ester of HEMA. All chemicals were analytical grade and purchased from Sigma Al- BEMA (0.015 mol; 3.0996 g), AMPS (0.015 mol; 3.10875 g) and EOA drich Chemicals Co. Octadecylamine (ODA), tetraethylene glycol (0.015 mol; 11.94 g) were dissolved in 40 mL of THF under nitrogen at- (TEG), 2,2-dichlorodiethyl ether(DDE), and sodium hydroxide were mosphere. The reaction temperature was increased to 70 °C followed by used for etherification of ODA as to prepare dihexaoxy octadecyl amine adding ABIN 0.005% (wt.% related to the total weight of BEMA and (EOA) as described in previous works [25].2-Acrylamido-2- AMPS) as initiator. The reaction temperature of the mixture was kept methylpropane sulfonic acid (AMPS) and hydroxyethyl methacrylate constant at this temperature for 12 h. Triphenyl phosphine (Ph3P; (HEMA) were used to prepare copolymer and 2,2-azobisisobutyronitrile, 0.015 mol related to BEMA) was added to the reaction mixture and AIBN, used as initiator for radical polymerization. Bromoacetyl chloride the reaction proceeded under reflux for 10 h. The reaction product

(BAC) and triphenyl phosphine (Ph3P) were used to esterify HEMA. Sol- was precipitated using acetone. The product was dried in vacuum vents such as tetrahydrofuran (THF), xylene, toluene, n-heptane, ethanol oven at 45 °C until constant weight. The polymer and polymer products were analytical grade and used without further purification. were designated as AMPS-EOA/HEMAP and AMPS-EOA/HEMA. The The specifications of sea water used to prepare synthetic emulsions yield % and melting temperature of AMPS-EOA/HEMAP are 97.2% and with crude oil were reported in previous work [25]. The analyses of Ara- 58 °C, respectively. bian heavy crude oil produced from Ras Gara wells by Aramco, Saudi Arabia were determined and listed in Table 1. The asphaltene fractions were characterized by molecular weight (g/mol), aromatic contents, 2.4. Characterization and hetero atoms contents according to the preparation methods de- scribed in ASTM D 1552-03 and ASTM D 5291-02. The asphaltene and Some heteroatom elements, such as sulfur, carbon, hydrogen, nitro- water contents are 5.3 and 0.145 wt.%, respectively. The synthetic gen and oxygen were determined according to the preparation methods crude oil water emulsions (90/10, 80/20, 70/30 and 50/50 vol%) were described in ASTM D 1552-03 and ASTM D 5291-02. prepared using mechanical homogenizer at 9000 rpm for 30 min at FTIR (Perkin-Elmer model 1720 FTIR), 1HNMR and 13CNMR spec- room temperature. troscopy model a 400 MHz Bruker Avance DRX-400 spectrometer were used to confirm the chemical structure of AMPS-EOA/HEMA and 2.2. Synthesis procedure a-Preparation of AMPS-EOA/AMPS AMPS-EOA/HEMAP. The aromatic carbons and hydrogens of asphaltene were acquired from the 5 w/v% asphaltene solution in CDCl3 and C2Cl3 Equal molar ratios of AMPS (0.015 mol; 3.10875 g), HEMA (1:1 v/v) and used to analyze the aromaticity of the asphaltene fraction (0.015 mol; 1.9521 g) and ODTE (0.015 mol; 11.535 g) were mixed in extracted from Arabian crude oil. 20 mL of THF under stirring in the presence of nitrogen atmosphere at room temperature to produce transparent light amber oil. The AIBN (0.005 wt.% related to AMPS, HEMA monomers) was added to the reac- tion mixture. The temperature of reaction was increased to 70 °C and remained constant for 12 h. The reaction product was dried using

Table 1 Physicochemical properties of the tested Arabian heavy crude oil.

Test Method Results

API gravity Calculated 23.9 Specific gravity 60/60 (°F) IP 160/87 0.896 Wax content, (wt.%) UOP 46/64 2.3 Asphaltene content, (wt.%) IP 143/84 5.3 Mwt (g/mol) 6350 Determined from Gel permeation chromatography Heteroatoms (w/w%) 6.5 Aromatic carbon (mol%) 49.0 Determined from 13CNMR Aromatic hydrogen (mol%) 7.81 Determined from 1HNMR Saturates (w%) 40.5 Aromatics (w%) 30.8 Resins (w%) 22.3 Fig. 1. Single-droplet protocol apparatus. Download English Version: https://daneshyari.com/en/article/5409939

Download Persian Version:

https://daneshyari.com/article/5409939

Daneshyari.com