COLORIMETRIC DETERMINATION OF TRACES OF V(II) IN
PETROLEUM PRODUCTS USING SOLID 8-HQSENSOR
Ahmed Shahata,?, Hassan M.A. Hassana,b,?, M.F. El-Shahatc, Osama El Shahawyd
aDepartment of Chemistry, Faculty of Science, Suez University, Suez, Egypt
bEgypt Nanotechnology Center (EGNC), Cairo University, El-Sheikh Zayed Campus, 12588 Giza, Egypt
cDepartment of Chemistry, Faculty of Science, Ain Shams University, 11566, Abbassia, Cairo, Egypt
d Suez Oil Processing Co., Salah Neseeim Street, El Zaytiat, Suez, Egypt
This study considered to be an application for the colorimetric determination of V(II) in petroleum products using solid chemosensor synthesized from mesoporous silica nanospheres and 8- Hydroxyquinoline (8-HQ).The new sensor showed a signal of the optical color that was easily created and transduced even at trace levels of V(II) target ions. The sensing responses of V(II) ions by using the 8-HQ sensor recorded to be up to nanomolar concentrations (?0.15 µg/L) with immediate response time (in the order of seconds). The 8-HQ sensor can be used easily with multiple regeneration/reuse cycles, by using diluted HCl acid to remove V(II) ions from the used sensor efficiently and formed a “metal-free”8-HQ sensor again. Despite the presence of active component species in petroleum product, the 8-HQ sensor has exhibited the selectivity behavior permitting V(II) ion-selective determination in petroleum product, such as in Coker gasoline. Using the8-HQ sensor for V(II) ion screening field indicates that it can be an alternative tool to a time and cost saving effective laboratory assays.
Keywords:Colorimetric determination; petroleum products; Vanadium; Digital image Colorimetry
* Corresponding authors: [email protected],[email protected]
Before: Plagiarism Quantity: 21% Duplicate
After: Plagiarism Quantity: 12% Duplicate
In nature, vanadium transition metal with the symbol (V) and atomic number (23) is found scarcely, and found naturally in chemically combined forms in approximately 65 different minerals and in fossil fuel deposits. The solitary metal always create a passive coat of oxide prohibit additional oxidation. It is a soft, silvery gray, flexible metal with the construction of good strength, anti-corrosion metal and stable against alkalis, acids and salt water. Slag from steel smelting, flue dust from heavy oil and mainly uranium mining – byproduct – are the sources of vanadium. Vanadium is fundamentally used in alloys, especially with steel (85% of all vanadium production) which can be used in axles, gears, and crankshafts, while 10% in titanium alloys and the rest 5% into all other uses 1. In makings of jet engines and high-speed aircraft, vanadium-aluminum-titanium alloy is utilized. Vanadium ion is considered as a toxin for some organisms if it was consumed in large amounts. Vanadium oxide and some of its salts are considered middling toxic. Vanadium (II) compounds are considered to be reducing agents, but vanadium (V) compounds are oxidizing agents, while vanadium (IV) compounds predominatingly subsist as vanadyl compounds containing VO(II)center2.
Vanadium proved to form more than 11 species of oxyanions compound in the aqueous solution, the formation of those species are related to concentration and pH value 3, at pH 12-14 the tetrahedral orthovanadate ion (VO4)3? used in protein crystallography to learn more about the phosphate biochemistry due to the similarity between (V) and (P) in size, charge, and crystallography 4,5. The tetrathiovanadate VS43? is analogous to the orthovanadateion 6.Findings revealed that vanadium reacts with many organic reagents to form a complex but with different limitations as an example some of the regents are not selective 7 others are not sensitive while others are not stable 8 and some complex formation takes a long time 9. Toxicity of vanadium considered industrial hazard so, it is ecologically, a chemical pollutant.
Crude oil is a rich mixture consist fundamentally of; numerous components of hydrocarbons, a few of sulfur, nitrogen, halogen and oxygen compounds, and trace amounts of metals such as vanadium, nickel, zinc, iron, copper, lead, magnesium, sodium, molybdenum, and others. Mostly V(II) and VO(II) are present as porphyrins and nonporphyrins. Relating to the biological origin, metalloporphyrins are among the first compounds identified, Treibs proposed that it transformed from plant chlorophylls so, it essentially used by geochemists for greater understanding the geochemical origin of petroleum source. Many troubles were predicted in the hydrogenation catalysts used in treatment processes if trace metals such as vanadium and nickel metalloporphyrins are present in the stream. 10.
Quantitative determination of the trace metals in the crude oils have a significant roles in recognizing the geochemical characterization of its source and origin, to understand the depositional environments and source rock, their proportions have been recorded to be a beneficial agent in studies of oil-oil rectification and oil-source rock linkage, they are indicatives of the source rocks and also in the oil industry and environment for meaningful impact assessment. Crude oil metal ions (naturally found or added) come into the environment through different processes such as exploration, production, refining, transportation, and storage; they are considered emulsion stabilizers 10.The vanadium content in crude oil will vary according to the source of oil, its concentration fluctuates between 40 to about 130 parts per million, i.e., 0.004% to about 0.013% by weight 11.
8- Hydroxyquinoline “oxine” can be used as a chelating reagent used in the determination of metals. Modern global researches proved that it has a replaceable hydrogen atom that is replaceable by a metal, and a heterocyclic nitrogen atom, which build a five-membered ring with this metal 12. It is a bidentate ligand and forms stable complexes with several metal ions. The potent coordinating ability and good metal recognition properties of 8- Hydroxyquinoline make it able to widely be used for analytical and separation purposes and also for chelating metals. 13.
The study of porous materials, especially mesoporous silica is in the high request because of their prospect use in detection systems. High regular channels, wide surface area, narrow pore-size distribution, and a harmony pore sizes over a wide range are collected advantages for the mesoporous silica. These notable properties have significant influence to improve the electrochemical signal and reinforce the charge transport to understand the metal coordination with specific color optimization. Furthermore, the mesoporous materials have numerous applications such as catalysis, chemical sensing probes, pre-concentrators, molecular filters, and carriers for the making of other detectors 14.
High stability of chemosensors makes it of suitable use in many purposes. They detect the tested ions with sensitivity and selectivity and speedy response time, including non-destructive, non-expensive, low detection limit, easy and safety while working with flammable and explosive compounds. Therefore, they are presently required to analyze the ultra-trace levels of environmental pollutants. So, many studies have been reported for colorimetric detection and removal systems of several analysts 15-24.
The RGB (Red, Green, and Blue) color model uses integrations of these lights against a black background to make the colors visible on a computer monitor or television screen. In the RGB pattern, the basic colors are red, green, and blue. The techniques of digital image analysis depending on the analysis of those essential color components gained from digital images. Digital camera is used to developing the images utilizing charge-coupled devices, where the light reflected from the tested colored bodies passes and form a red, green, and blue colors in different cases. After measuring and adjustment, the data were gained as individual RGB values, and the final color was composed of the additive data of the three RGB filters, after, the basis concentration of illicit material, used to calibrate the images by testing the RGB amounts obtained from the capture of digital images of hypothetical. This effort gave the fundamentals of the semi-quantitative analysis of illicit samples containing an unknown quantity of material 25.
In this paper, 8- Hydroxyquinoline was used as an indicator for the fabrication of a newly developed chemosensor to detect V(II) in aqueous and non-aqueous solutions to be an operative implementation for visual vanadium V(II) ion in petroleum samples. Using MSN, as a platform for 8-HQ established to be a simple, highly selective and sensitive spectrophotometric method for determination of vanadium (II) ions. The effect of different parameters such as pH and the amount of the chemosensor were examined. The complex formation time and the other metal ions interference effect were evaluated. The method has wide linear range, low detection limit, high sensitivity and selectivity and high repeatability that successfully have been used for determination of V(II) ion content of petroleum products.