Petrochemical Properties Research Articles

Potential biofuel exploitation from two common Vietnamese Euphorbia plants (Euphorbiaceae)

AbstractIn this work, two common Vietnamese Euphorbia plants, Euphorbia tirucalli Linn. (the milk bush) and Euphorbia tithymaloides Linn. (the milk hedge), have been investigated for potential use as biofuels. Their aerial parts were macerated with different solvents [petroleum ether, ethyl acetate (EA), methanol and water] to obtain extracts. The extracts were put through petrochemical composition analyses, including elemental analysis, Fourier transform infrared spectra recording and fatty acids composition analysis by HPLC. Subsequently, extracts were subjected to thermal gravimetric analysis for determination of some petrochemical contents. In addition, the gross calorific values (GCVs) of all extracts were determined and compared with those of other Euphorbia species and fuels. The obtained results showed the high petrochemical properties of Euphorbia tirucalli and moderately high ones of Euphorbia tithymaloides. Their estimated total rubber content values were then determined and compared with those of strains of other countries. The petroleum ether extract possessed the highest GCV, followed by the EA extract of E. tirucalli, then the EA extract of E. tithymaloides. Their GCVs were higher than those of some of other Euphorbia plants, conventional fuels like anthracite or lignite, and asymptotic to those of present fuels, including diesel and gasoline. Together with the plants’ well‐known tolerance of harsh conditions, such interesting phytochemical and petrochemical results significantly contribute to the potential for biofuel exploitation of Vietnamese E. tirucalli and E. tithymaloides. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd.

Clastic rock geochemistry of the Sirohi Basin, Aravalli Craton, NW India: Implications for paleoweathering, provenance and geodynamics

• Petrographic and geochemical data of clastic rock formations in the Sirohi Basin. • Two wacke horizons with distinct textural and chemical characteristics. • Geological evolution of the Sirohi Basin and relation with geodynamics of the Indian Shield. Sirohi Basin of Trans-Aravalli Region, Rajasthan preserves a thick clastic sequence composed of phyllite and metasandstone. Based on their petrochemical properties, metasandstone is classified as K-feldspar rich wacke (Wacke I) and plagioclase rich wacke (Wacke II). Wacke I is characterised by higher K 2 O, Fe 2 O 3 and lower CaO, Na 2 O, and Na 2 O/K 2 O ratios than Wacke II. Chemical Index of Alteration (CIA) and the A-CN-K systematic prescribe least chemical weathering for the sediments of Wacke II, moderate for Wacke I and moderately intense for phyllite of the Sirohi Basin. Chemical traits perceived from UCC spidergrams, discrimination function diagrams, etc. in conjunction with immobile element ratios (e.g., Al 2 O 3 /TiO 2 , Th/Sc, La/Sc, La/Co, Th/Co, Eu/Eu*, La/Sm N and Gd/Yb N ) establish dual-source terrains for Sirohi clastics, one with preponderance of felsic componets and other mafic plus felsic ingrediatns. The petrochemical signatures of Sirohi clastics, though suggest procurement of detritus form diffrent sources but consanguineous evolution in the Sirohi Basin, in response to extensional stresses. :

Magnetic Properties of Impact UHPHT Glasses, Melt Rocks, Suevitic Breccia and Target Rocks of the Giant Kara Meteorite Crater (Pay-Khoy, Arctic Seashore, Russia)

The shock waves can strongly change the physical properties of the target rock minerals including their density and magnetism which determine petrochemical properties of impactites finely as a rule are resulted in astroblemes contours on geophysical maps. Following to the aero-magnetic mapping data the non-magnetic sedimentary rocks of the Kara target create a zero and negative magnetic field with an average intensity of -1 nT, against the background the southwestern region of the Kara astrobleme provides the positive magnetic anomalies with an intensity of 1 to 3 nT which are in a good correspondence with the Pay-Khoy ridge structure general orientation. The Kara dome is characterised with an isometric negative anomaly of intensity -5 nT. Here we present the magnetic properties of the different kinds of the Kara impactites including impact ultra-high pressure high temperature (UHPHT) melt glasses, melt rocks and suevitic breccia compare to sedimentary target rocks. The petrophysical measurements presented the specific magnetic susceptibility of the impactites in the range of 8 to 48×10-8 SI units, where the UHPHT glasses have the limits from 9 to 38×10-8 SI units (15×10-8 SI units, in average). The sedimentary target is characterised with essentially lower level of magnetic susceptibility – no higher than 15×10-8 SI units, where limestone has it about zero. Following to the similar level of the iron content within the impactites and target rocks the magnetism of the Kara impact melts is explained rather by changing of magnetic properties by the impact process. One of the possible source of magnetism can be partially an iron-containing matter of the asteroid component in the form of pyrrhotine accompanied with Ni and Co impurities. Also, we cannot exclude partial presence of magnetic iron component directly within the quenched impact glasses including UHPHT variety.

On the Genesis of “White Granite” from the Kester Harpolith, Arga–Ynnakh–Khaya Pluton, East Yakutia

Abstract—The problem of the origin of “white granite” in the Kester harpolith of the Arga–Ynnakh–Khaya Pluton is discussed. The morphology, occurrence, and nature of the intrusive contacts of the Kester harpolith prove its magmatic origin. The petrographic and petrochemical properties of “white granite” allow its identification as a postorogenic rare-metal high-phosphorus granite of the Li-F geochemical type. The magmatic genesis of the “white granite” texture is supported by statistical methods. The composition, typomorphic properties, ontogenetic features internal structure and relationship of accessory minerals indicate that the major accessories of the granite, that is, cassiterite, columbite, tantalite, “wolframoixiolite,” zircon, and ferberite, were formed at the late stage of the low-temperature rare-metal granitic melt. The Kester harpolith within the Arga–Ynnakh–Khaya granite pluton and the eponymous tin–rare-metal deposit genetically related to it are a part of the Far East Superprovince of rare-metal granites.

Micro- and Macroscale Consequences of Interactions between CO2 and Shale Rocks

In carbon storage activities, and in shale oil and gas extraction (SOGE) with carbon dioxide (CO2) as stimulation fluid, CO2 comes into contact with shale rock and its pore fluid. As a reactive fluid, the injected CO2 displays a large potential to modify the shale’s chemical, physical, and mechanical properties, which need to be well studied and documented. The state of the art on shale–CO2 interactions published in several review articles does not exhaust all aspects of these interactions, such as changes in the mechanical, petrophysical, or petrochemical properties of shales. This review paper presents a characterization of shale rocks and reviews their possible interaction mechanisms with different phases of CO2. The effects of these interactions on petrophysical, chemical and mechanical properties are highlighted. In addition, a novel experimental approach is presented, developed and used by our team to investigate mechanical properties by exposing shale to different saturation fluids under controlled temperatures and pressures, without modifying the test exposure conditions prior to mechanical and acoustic measurements. This paper also underlines the major knowledge gaps that need to be filled in order to improve the safety and efficiency of SOGE and CO2 storage.

New weathering indices for evaluating durability and weathering characterization of crystalline rock material: A case study from NE Turkey

There are several methods to characterize petrochemical properties of crystalline rocks. One method is based on the ionic model. In the model, large oxygen atoms of the rock-forming minerals are close-packed framework structures. The distribution of cations, which is defined by the “Cation-Packing Index” or the k-value for each (stoichiometric) mineral phase, can be correlated with the petrophysical properties. These properties, representing the engineering behavior of the rock materials show a dependence on the physical and chemical changes due to weathering. The fundamental systems of the chemical weathering of rocks are the leaching of the alkaline and alkali-earth elements and the redistribution of the residual elements into secondary minerals. In this study, these conditions are considered as the basis for new petro-chemical weathering indices based on the cation-packing value for evaluating weathering characterization of crystalline rocks. These indices are the k-product index, the k-leaching index and the k-weathering index. The k-product index represents the quantity of the weathering product suggested in this study, whereas the k-leaching index represents the amount of chemical leaching during the weathering. The k-weathering index was defined as the sum of the k-leaching index and the k-product index. In addition to these new engineering indices, a k-durability index based on a slake durability index and the k-value of the rock materials was suggested in this study to estimate the durability and the mechanical properties of rock materials. These indices were applied to granitic rock samples weathered to various degrees, from the Kurtun Granodiorite in northeastern Turkey. The results of the regression analysis performed in this study show that the k-weathering index can be used as a weathering indicator and that the k-durability index can be used to evaluate the durability and the mechanical behaviors of the investigated samples. It would be useful to conduct further research to confirm the results of the present study.

태백산지역과 인근에 분포하는 우백질 화강암체의 존재

태백산지역과 주변의 선캠브리아기 고기 화강편마암류 및 고생대 퇴적변성암류 분포지역에 산포되는 소규모 암주상 우백질(알카리) 화강암류는 기존 연구에서 다소 기재가 등한시되어왔다. 그 구분을 위하여 야외노두의 육안상 차이, 광물조성 및 지화학적 특성 등을 파악하였다. 고기 화강편마암(고기 화강암질암)류는 미그마타이트조직을 나타내거나, 유색광물류에 의한 편마구조가 뚜렷한 편이다. 그리고, 부분적으로는 석영과 장석류의 녹회색화로 어두운 암색을 나타내거나, 복운모화강암이나 우백질화강암의 특성을 나타내기도 한다. 이에 비하여 후기 우백질화강암류는 훨씬 밝은 암색을 나타내며 구성광물은 석영, 장석류, 백운모 외에 각섬석류, 견운모, 전기석류 및 레피도라이트(lepidolite) 등을 소량 포함하기도 한다. 모든 우백질 화강암류는 칼크-알카리계열이며, 과알루미나형으로서 S-형에 속한다. 또한, 이들은 분화를 거치면서 알바이트화(albitization) 등에 의하여 CaO와 철함량이 상대적으로 감소하였으며, 영운암화(greisenization) 작용으로 인하여 <TEX>$K_2O$</TEX>와 <TEX>$Na_2O$</TEX>는 부화되었다. The Taebaegsan region and its vicinities mainly consist of Precambrian granitic gneisses and Cambrian meta-sedimentary rocks. And lots of leucocratic(alkali) granites smaller than the stocks are found here and there. Therefore the presence of leuco-granites is not properly described yet in the former studies. For the effective distinction of several granitic rocks, outcrop characteristics, mineral identification, and petro-chemical properties were studied. Some part of granitc gneisses could be classified into typical metamorphic rocks such as migmatites and banded gneisses. And some shows rather dark appearance with gray quartz and feldspars, and others two mica granites, leucocratic ones etc. But all of leucocratic granites of the region usually show bright milky white to beige color. Since they mainly consist of quartz, feldspars, muscovite, and small amounts of sericites, amphiboles, tourmaline and lepidolite. And all of alkali granites belong to the calc-alkalic, peraluminous and S-type in character. During magmatic differentiation of leucocratic granites, CaO and total Fe contents are clearly decreased than those of the older granitic rocks. On the other hand, magmatic evolution also had induced the greisenization and albitization which enriched the relative amounts of alkali elements such as <TEX>$K_2O$</TEX> and <TEX>$Na_2O$</TEX>.

Geotectonic implications of Permian and Triassic carbonate successions in the Central Plain of Thailand

Two carbonate successions constituting Paleozoic–Mesozoic basement rocks distributed in the Nakhon Sawan–Uthai Thani area in the Chao Phraya Central Plain of Thailand were investigated to understand basic geotectonic subdivision of the area. Of them, we newly proposed the term Khao Pathawi Limestone for a Triassic succession exposed in eastern Uthai Thani Province, from which a rich foraminiferal fauna consisting of Aulotortus sinuosus, A. friedli, Tetrataxis inflata, Diplotermina subangulata, Agathammina austroalpina, Ammobaculites rhaeticus, Alpinophragmium perforatum, Gaudryina triadica, and others was discriminated. They clearly suggest a Late Triassic age and highly probably Norian/Rhaetian. This limestone succession is considered to have formed a carbonate platform and is comparable to those on the Triassic Lampang–Phrae Basin in the Sukhothai Zone of Northern Thailand. In contrast, the Uthai Thani Limestone exposed just west of the Khao Pathawi Limestone, in the form of NNW–SSE trending monadnocks, represents a slightly metamorphosed, thick-bedded Permian succession. Its outcrop alignment is distinct from the north–south trending Khao Pathawi Limestone, suggesting their structural separation. The Uthai Thani Limestone is correlated to the Sai Yok Formation and the Ratburi Limestone, both of which are well-known as typical Permian successions on the Sibumasu Block. By integrating these data from the carbonates, together with available geological information from other Paleozoic–Mesozoic basement units in the Central Plain, such as petrochemical properties of granitoids and volcanic/volcaniclastic rocks and litho- and chronostratigraphic characteristics of sedimentary successions, including the Permian Khao Gob Chert, we explain that the central part of the Nakhon Sawan–Uthai Thani area where the Khao Pathawi Limestone and the Khao Gob Chert are distributed, corresponds geotectonically to the direct southern extension of the Sukhothai Zone of Northern Thailand. Thus, as is the case of Northern Thailand, we recognized three geotectonic domains also in the Central Plain; they are the Indochina Block (part of Cathaysialand), Sukhothai Zone (Permian–Triassic island arc system), and Sibumasu Block (part of Gondwanaland) from east to west. To the south, the Sukhothai Zone probably extends to the Klaeng Zone of Southeast Thailand. In this paper, Endotriada martiniae Ueno, Miyahigashi and Charoentitirat, n. sp. from the Khao Pathawi Limestone is also described.

Magnetic and petrochemical properties of rocks from the Red Sea rift zone

The magnetic and petrochemical properties of basalts dredged from the rift zone at the southern part of the Red Sea at approximately 18° N are studied. The conditions of their formation and evolution are elucidated. The formation of basalts is found to occur in two stages differing in their magma supply rates and redox conditions. Special features of magnetic behavior and the anomalous geomagnetic field in the region were used to determine the sites where the rocks had experienced strong thermodynamic effects (tectonic strain, deformation, heating, etc.). The conditions in which natural remanent magnetization of the basalts was formed are estimated.

Estimation of Harmonic Mean of a Lognormal Variable

The harmonic mean has numerous engineering applications including characterization of the large- scale effective permeability in layered porous media, characterization of petrochemical properties of heteroge- neous media, and the design of declining rate filter beds. The U.S. EPA also recommends the use of the harmonic mean daily streamflow as a design streamflow for the protection of human health against lifetime exposure to suspected carcinogens. The sampling properties of various estimators of the harmonic mean are derived and compared for observations arising from a lognormal distribution. Previous applications have recommended the use of a moment estimator of the harmonic mean. We document that the moment estimator of the harmonic mean exhibits significant upward bias and large root-mean-square error, particularly for large skews. A maximum likelihood estimator of the harmonic mean is generally preferred because it is nearly unbiased and can provide dramatic reductions in the root-mean-square error, compared with the moment estimator. In addition, a maximum likelihood estimator of the generalized mean (or p-norm) of a lognormal distribution is introduced.

Bidders For Mexican Petrochemical Assets Proceed With Caution

As the Latin phrase goes, caveat emptor—let the buyer beware. This seems to explain the hesitation of prospective bidders in Mexico's intended privatization of its petrochemical industry. In November 1995, Petroleos Mexicanos (Pemex), Mexico's national oil company, made its first formal presentation to sell the first of 10 major petrochemical complexes to international chemical producers. The government intends to sell 61 plants within the 10 complexes. But so far, only one bidder—a partnership of two U.S. companies—has publicly announced its interest in vying for Mexico's first offering: the five ammonia plants at the Cosoleacaque petrochemical site, which also contains a p -xylene facility and a hydrogen production plant. Potential bidders seem hesitant to jump at the Mexican government's privatization of its petrochemical properties. In light of the economic recession that Mexico plunged into after it devalued the peso in December 1994, that hesitation is understandable. But it could also be that the p...

Taphonomy of half and compressed ammonites from the lower jurassic black shales of the toyora area, west Japan

The origin of half and compressed ammonites from the Lower Jurassic (Upper Pliensbachian to Lower Toarcian) black shales of the Nishinakayama Formation in the Toyora area, west Japan, is discussed. Ammonite shells horizontally embedded in the black shales reveal two types of fossil preservation; (1) “half” ammonites without an upper flank, and (2) complete ammonites with both upper and lower flanks. Specimens of the first type mostly lack a calcified shell wall, leaving only a wrinkled periostracum, while those of the second type retain a calcified shell wall. Most specimens have suffered from a lateral deformation during sediment compaction, but the ratio of deformation is less than 40% at many localities. The mode of ammonite preservation correlates well with the petrochemical properties of the fossil-bearing shales, and the shales comprising complete ammonites are rich in carbonate CaO and calcite as compared with the “half” ammonite-bearing shales. These lines of evidence strongly suggest that the upper flank of the “half” ammonites had been dissolved away in early diagenesis before its complete burial. Thus the upper flank might have been initially exposed to the seawater. As the “half” ammonites are confined to the shales associated with layers of tiny sedimentary pyrite crystals, dissolution of aragonitic ammonite shell walls and septa might have happened under anaerobic or oxygen-depleted bottom conditions.

Geochemical and geothermal parameters for the Pechenga and Ricolatva regions, Baltic shield

Petrochemical properties and uranium and potassium contents of core samples for the boreholes in the Pechenga and Ricolatva regions of Kolsky peninsula are investigated. The average concentrations of uranium and potassium in gabbroes is equal to 0.4 ppm and 0.6%, in gneisses 0.5 ppm and 2.32% respectively. Heat flow from the crust by radioactive heat production in these regions is about 8.37 – 12.56 mWm −2 (0.2 – 0.3 HFU). The data obtained allow us to suppose that a significant amount of heat is generated in the upper mantle of the earth under these regions.

Interchange of Chemical Components between Granitic Intrusions and Aureole Rocks of South Kyushu, Japan

Studies of the chemical and mineralogical properties of pelitic country rocks of South Kyushu into which the Ôsumi, Shibisan, and Takakumayama granitic intrusives were emplaced during the Miocene suggest that exchange of chemical components between the granitic systems and country rocks accompanied the metamorphic and intrusive processes. Pelitic rocks of unusually uniform initial compositions, collected from the same stratigraphic horizons at localities adjacent to and distant from the granitic intrusives, are distinctly different in chemical composition. Some elements, notably Na and K, are distributed in a different manner within the several aureoles; the differences in Na-K distributions appear to reflect different petrochemical properties of the intrusives. Country rocks of granitic intrusives of similar petrochemical properties show similar distributions of elements. Therefore, the processes responsible for the distribution of elements in the country rocks are related to the plutonic processes that caused the entry of the granitic intrusives.