N pentane

Castor oil used was provided by PolyUrethane Company (Betim, Minas Gerais, Brazil). Crude glycerol, a co-product of biodiesel production, was kindly provided by Petrobrás (Usina Darcy Ribeiro—Montes Claros, Minas Gerais, Brazil). The crude glycerol has about 91% of glycerin, 5% of inorganic compounds (transesterification catalyst, acids, etc.), 1% of methanol, and about 3% of water and biodiesel, oleine, monoglicerides, and others. Pure glycerol (99.5%) was supplied by Synth. The isocyanate source (Desmodur 44 V 20), a mixture of 4,4′-diphenylmethane-diisocyanate, was supplied by Bayer Company. The surfactant was Tegostab 8460 (Evonik, Essen, Germany), a polyether-modified polysiloxane. The catalyst used in polyurethane foams synthesis was DBTDL (dibutyl tin dilaurate), an organometallic catalyst, manufactured by Evonik. The blowing agents used were cyclopentane (Sigma Aldrich, St. Louis, MO, USA), n-pentane (Sigma Aldrich, St. Louis, MO, USA), and distilled water.

Reagents such as ammonium formate and solvents such as water, methanol, and LC-MS grade acetonitrile were purchased from Sigma-Aldrich (Darmstadt, Germany). Ethyl acetate (analytical reagent grade) was obtained from Fisher Chemicals (Bremen, Germany). Propan-2-ol and n-pentane for trace analysis were purchased from Sigma-Aldrich (Darmstadt, Germany).

Chemical solvents toluene, acetonitrile, and n-pentane were purchased from Sigma Aldrich and Acros Organics, all ≥99% purity. Dichloromethane (DCM), methanol (MeOH) and petroleum ether were distilled in-house. The surfactants used in verification studies were tetradecyltrimethylammonium bromide (CH₃(CH₂)₁₃N(CH₃)₃Br; C₁₄TAB) and dodecyltrimethylammonium bromide (CH₃(CH₂)₁₁N(CH₃)₃Br; C₁₂TAB) 99% and 98% purity respectively, obtained from Sigma Aldrich. The two compounds differ by only two methyl groups and their mixtures were used to test sensitivity of the ultrasonic instrument to multiple micellarisation. Milli-Q 18 M Ω deionised water was used to make C₁₄TAB and C₁₂TAB solutions.
Asphaltenes were precipitated from four petroleum samples: E1 with E2 and E3 with E4 are from two different source rocks respectively and all are from different reservoirs. E1 and E2 are from South America and E3 with E4 are from North America. Samples were selected such that there are two biodegradation aliquots from a source rock. Biodegradation analysis was performed on deasphalted petroleum using thin layer chromatography with short column elution to obtain aliphatic and aromatic fractions. The latter were then analysed by gas chromatograohy-mass spectrometry and relative biomarker abundance compared with Wenger et al.^{60 ,61} scales.

For this study, commercial nanomaterials (NM), listed in Table 1, of different chemistries, morphologies and sizes have been selected in order to evaluate the effect of these intrinsic properties of the nanomaterial on their dispersibility, as well as on the thermal properties of the final nanofluid.
For the refrigerant, n-pentane (reagent grade, 98% from Sigma-Aldrich) was selected because of its chemical similarity to commercial hydrocarbon refrigerants (such as isobutane R600a and propane R290) and because it is in liquid phase at room temperature, which facilitates its manipulation and characterization for the preparation of the nanofluids.

The utilized chemicals for the provision of NiGA MOF including nickel(ii) chloride hexahydrate (NiCl₂·6H₂O), gallic acid, and potassium hydroxide were provided by Merck (Darmstadt, Germany). Deionized water was bought from Ghazi Co. (Tabriz, Iran). The target compounds of the survey including BHT, DNBP, DIBP, DEHP, and DEHA were purchased from Sigma-Aldrich (St Louis, MO, the USA). Their chemical structures and physicochemical properties are consolidated in Table 1. The desorption solvents including diethyl ether (DE), tert-butyl methyl ether (TBME), carbon disulfide, n-pentane, and petroleum ether (PE) were provided by Sigma-Aldrich. Sodium chloride and sodium sulfate for performing the salting-out effect were from Merck. The elution solvents including carbon tetrachloride, 1,2-dibromoethane (1,2-DBE), and 1,1,1-trichloroethane (1,1,1-TCE) were purchased from Janssen (Beerse, Belgium). Sodium hydroxide and hydrochloric acid solution (37%, w/w) were purchased from Merck and utilized for pH adjustment. A methanolic stock solution with a concentration of 250 mg L⁻¹ (with respect to each analyte) was prepared and used for direct injection into the separation system and also spiking into the deionized water and surveyed aqueous samples.

Sodium hydroxide (NaOH, >98%) and 1,1,1,5,5,5-hexafluoro-2,4-pentanedione (H-hfa, >98%) were purchased from Strem Chemicals and used without further purification. Monoglyme (1,2-dimethoxyethane, 99.5%), diglyme (bis(2-methoxyethyl)ether, 99.5%), triglyme (2,5,8,11-tetraoxadodecane, >98%), tetraglyme (2,5,8,11,14-pentaoxapentadecane, >99%), dichloromethane (CH₂Cl₂, >99.5%), and n-pentane were purchased from Sigma Aldrich.