MEASURING KEROGEN, SOLID ORGANICS, AND OIL PRODUCTION POTENTIALS OF UNCONVENTIONAL SOURCE ROCKS USING SOLID TYPE 20-MHZ NMR TECHNIQUES

It is well known that the NMR relaxation time T2 is proportional to the molecular mobility of water or hydrocarbons in rocks. In unconventional tight rocks, water and hydrocarbons are trapped in small pores of nanometer sizes, and their molecular mobility is severely restricted, causing the NMR T2 to be much shorter than that of conventional cases where pore sizes are in micrometer ranges. There are demands for advanced NMR techniques to study those solid-like bound hydrocarbons. In the meantime, it is of great interest for petrophysicists and geochemists to understand kerogen models in order to determine thermal maturity and hydrocarbon potential of organic-rich source rocks, and always attractive to have practical techniques that are nondestructive and less time consuming. In this study, a series of NMR 1D and 2D experiments have been performed on various types of source rocks with emphasis on short NMR T2 components, from sub-milliseconds down to a few microseconds, which are associated with kerogen, heavy hydrocarbons, and small hydrocarbon molecules bound in nanopores. The results show that the NMR CPMG pulse sequence used for the T2 data acquisition is (1) not capable of detecting and measuring the very rigid solid component of the T2 shorter than 30 microseconds, which is thought from kerogen, and (2) uncertain for the NMR components with T2 between 30 microseconds and 0.1 ms, which is dependent on the inter-echo spacing time (TE). Instead, the solid echo-pulse sequence was used to acquire the early time NMR signals that represent rigid solid matters, such as kerogen, in rock samples that have short relaxation times of less than 20 microseconds. The NMR solid echo signals were fitted into a composition of a Gaussian plus exponential functions to better describe NMR responses of source rocks with the shortest relaxation time of a few microseconds. The Gaussian component in the NMR signal is the measure of rigid solids associated with kerogen in the source rock. Model rock samples of thermally immature outcrops of the Upper Jurassic Kimmeridge Clay Formation in the UK and the Green River Shale Formation in the USA were used for comparison studies between the low field solid NMR techniques and geochemical analytical methods. The thermal maturities of the samples were artificially altered through the hydrous pyrolysis method at selected temperatures. The comparison results show that the amplitude of the Gaussian component measurement by NMR strongly correlated with the S2 of pyrolysis. The NMR relaxation times of the solid portion are directly proportional to the thermal maturity determined by organic petrography. This study concludes that the nondestructive solid NMR method provides an alternative and rapid way to study solid organic matters. The combined techniques enable us to further study kerogen models and hydrocarbon-generating potentials in organic-rich source rocks.

Al and Zr Porous Clay Heterostructures as Removal Agents of Basic Blue-41 Dye from an Artificially Polluted Solution: Regeneration Properties and Batch Design

The removal of Basic Blue-41 dye molecules was carried out by using two doped porous clay heterostructures by aluminum (Al) or zirconium (Zr) species. The proposed method of synthesis showed its efficiency, starting from Al or Zr intercalated hydrolyzed species, prior to its reaction with dodecylamine (C12 amine) and tetraethyl orthosilicate (TEOS) as a silica source. The intercalated precursors and their porous clay heterostructures (PCH) derivatives were characterized by different techniques. Solid NMR technique proved the presence of Al species into the intercalated silica between the clay sheets, and in addition to Si in different environments within the PCH materials. The Zr-PCH material exhibited a higher surface area and pore volume compared to its Al-PCH counterpart, with a mesoporous character for both materials. A maximum removed amount of 279 and 332 mg/g was achieved and deduced from the Langmuir equation. The regeneration tests revealed that the removal efficiency of Zr-PCH was retained after five regeneration runs, with a loss of 15% of the original value; meanwhile, the Al-PCH lost 45% of its efficiency after only three cycles. A single-stage batch design was proposed based on the Langmuir isotherm parameters. The increase of the removal capacity of Zr-PCH led to the reduction of the required amounts for the target removal of BB-41 dye compared to Al-PCH.

Supreme and selective capture of one of the most dangerous metal, URANIUM, by phosphonate-functionalized ordered mesoporous silica: surface chemistry matters the most

<p>Designing of materials for effective uranium removal remains an open challenge. In the present work, we present a one-step co-condensation synthesis of a phosphonate functionalized ordered mesoporous silica (OMS-P). This novel material was characterized by various physicochemical methods (HR-TEM, SEM, N<sub>2</sub>sorption, XPS, solid NMR, low-angle XRD, and FTIR) and its ability to remove U(VI) by adsorption from aqueous solutions was studied. The maximum adsorption capacity reached 345 mg/g in 10 minutes, the highest reported up to day for silicas at pH = 4 and almost four times higher than for the unfunctionalized silica. Even more interestingly, the coexistence of other cations, such as Eu(III), did not affect adsorption capacity and selectivity. The adsorption results were evaluated based on various theoretical models in order to conclude regarding the kinetics. Moreover, the main interactions responsible for the increased U(VI) removal efficiency and in general the role of surface chemistry were analyzed by spectroscopic characterizations of OMS-P before and after adsorption.</p>

Synthesis of Binderless ZK-4 Zeolite Microspheres at High Temperature

Binderless zeolite macrostructures in the form of ZK-4 microspheres were prepared using anion exchange resin beads as shape directing macrotemplates. The particles were synthesized under hydrothermal conditions at different temperatures and treatment times. The influence of the different synthesis parameters was investigated by X-ray diffraction, scanning electron microscopy, fluorescence X, nitrogen adsorption measurements and 29Si solid NMR. Fully crystalline spheres similar in size and shape to the original resin beads were obtained by a hydrothermal treatment at the highest temperatures (150 - 180 °C) for a short treatment time of 24 h. The synthesized microspheres showed to be promising in the molecular decontamination of Volatile Organic Compounds (VOCs).

Characterization of organo-kenyaites: thermal stability and their effects on eosin removal characteristics

ABSTRACTOrgano-kenyaites were prepared from a cetyltrimethylammonium hydroxide (C16TMAOH) solution and solid sodium kenyaite (Na2Si22O45.10H2O) mixture. The effect of the initial cetyltrimethylammonium solution on the structure of the intercalated materials was investigated by CHN analyses, X-ray diffraction (XRD), thermogravimetric analysis, SEM, and 29Si and 13C solid NMR techniques. For C16TMAOH concentration 0.25 mM, the Na+ cations were fully exchanged. Initial C16TMAOH concentrations higher than 0.25 mM had little effect on the intercalated amount of C16TMA+ cations. The organic cations content reached a plateau of 0.66 mmol/g. The arrangement model of C16TMA+ cations corresponded to a tilt of the organic cations to the silicate layers with an angle of 42° as deduced by XRD studies. The C16TMA+ cations exhibited mainly trans-configuration of the methyl chains, as was shown by solid 13C NMR. The thermal stability of the organo-silicates was studied using in situ FTIR and in situ XRD in the range 25–450°C. The C16TMA-kenyaites were stable at temperatures below 200°C. They collapsed at higher temperatures due to the decomposition of the intercalated surfactants. These organo-kenyaites were used to remove the acidic dye molecule, eosin. The removal tests were performed at varying conditions of initial dye concentrations, organic content in the organo-kenyaites and heating temperatures. In general, the organic modification improved the removal capacity of the Na-kenyaite from 2 mg of eosin/g to 60 mg of eosin/g, and this capacity was related to the organic contents and the calcination temperatures of the organo-kenyaites.

Optimal Surface Amino-Functionalization Following Thermo-Alkaline Treatment of Nanostructured Silica Adsorbents for Enhanced and Selective CO2 Adsorption

Special preparation of SBA-15 materials has been carried out for creating adsorbents exhibiting an enhanced and selective adsorption toward CO2. This creation starts from an adequate conditioning of the silica surface, via a thermo-alkaline treatment to increase the population of silanol species on it. CO2 adsorption is only reasonably achieved when the SiO2 surface becomes aminated after put in contact with a solution of an amino alkoxide compound in the right solvent. Unfunctionalized and amine-functionalized substrates were characterized through X-ray diffraction, N2 sorption, Raman spectroscopy, electron microscopy, 29Si solid-state NMR, and NH3 thermal programmed desorption. These analyses proved that the thermo-alkaline procedure desilicates the substrate and eliminates the micropores (without affecting the SBA-15 capillaries), present in the original solid. NMR analysis confirms that the hydroxylated solid anchors more amino functionalizing molecules than the unhydroxylated material. The SBA-15 sample subjected to hydroxylation and amino- functionalization displays a high enthalpy of interaction, a reason why this solid is suitable for a strong deposition of CO2 but with the possibility of observing a low-pressure hysteresis phenomenon. Contrastingly, CH4 adsorption on amino-functionalized, hydroxylated SBA-15 substrates becomes almost 5 times lesser than the CO2 one, thus giving proof of their selectivity toward CO2.

Synthesis Photosical Properties of Silicon-Containing Cross-Linked Polymer

Organic light-emitting materials in Organic Light-emitting Diodes(OLED) reserch in a very important posotion, the quality of materials directly affect the level of luminous efficiency of the device. We chose benzene 2,6-alkynyl, respectively, and tetrakis (4-bromophenyl) silane, tetrakis (3-bromophenyl) silane synthesis of new cross-linked polymer, the structure was characterized by solid NMR, by fluorescence chromatography UV crosslinking compound characterization of chromatographic performance in photophysical aspects may choose to add a new organic light-emitting material.