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Composition of Fracking Water
Published in Frank R. Spellman, Hydraulic Fracturing Wastewater, 2017
The development of cross-linked gels in 1968 was one of the major advances in fracturing fluid technology (Ely, 1994). When cross-linking agents are added to linear gels, the result is a complex, high-viscosity fracturing fluid that provides higher proppant transport performance than do linear gels (Ely, 1994; Messina, 2001; USEPA, 2004). Cross-linking reduces the need for fluid thickener and extends the viscous life of the fluid indefinitely. The fracturing fluid remains viscous until a breaking agent is introduced to break the cross-linker and eventually the polymer. Although cross-linkers make the fluid more expensive, they can considerably improve hydraulic fracturing performance. Cross-linked gels are typically metal ion–cross-linked guar (Ely, 1994). Service companies have used metal ions such as chromium, aluminum, titanium, and other metal ions to achieve cross-linking, and low-residue (cleaner) forms of cross-linked gels, such as cross-linked hydroxypropylguar, have been developed (Ely, 1994). Cross-linked gels may contain boric acid, sodium tetraborate decahydrate, ethylene glycol, and monoethylamine. These constituents are hazardous in their undiluted form and can cause kidney, liver, heart, blood, and brain damage through prolonged or repeated exposure. According to a Bureau of Land Management environmental impact statement, cross-linkers may contain hazardous constituents such as ammonium chloride, potassium hydroxide, zirconium nitrate, and zirconium sulfate (USDOI, 1998).
2 Nanotubes for Heavy Metal Ions Removal
Published in Zainovia Lockman, 1-Dimensional Metal Oxide Nanostructures, 2018
Nurulhuda Bashirom, Monna Rozana, Nurul Izza Soaid, Khairunisak Abdul Razak, Andrey Berenov, Syahriza Ismail, Tan Wai Kian, Go Kawamura, Atsunori Matsuda, Zainovia Lockman
Two main ingredients are needed; nanofiber and a Zr-precursor to produce the ZNTs by this method. The precursor can be Zr salt solution (zirconium nitrate, zirconium acetate, zirconium perpoxide, zirconium tert-butoxide, and zirconium acetylacetonate). The deposition process on the fiber can be done by immersing nanofibers in the precursor solution for a pre-determined time followed by heat treatment. During heat treatment, nucleation and crystallization of ZrO2 on the template will result in the formation of nanofiber-coated ZrO2. The nanofibers must then be removed to produce hollow fibers of ZrO2: nanotubes. The nanofibers used are often carbon-base (organic) like carbon nanotubes (CNTs) (Rao et al., 1997), cellulose (Huang and Kunitake, 2003) or carbon nanofibers (Ogihara et al., 2006). Figure 6.6 shows the scanning electron microscope (SEM) images of ZNTs prepared by a templated method against cellulose and a single ZNT is seen from the transmission electron microscope (TEM) image in Figure 6.6b. The TEM image of CNTs is shown in Figure 6.7a. After deposition and removal of CNTs, the resulting ZNTs are shown in Figure 6.7b. The template used does not have to be straight; in Figure 6.7a, a TEM image of carbon nanocoils is shown. Figure 6.7d shows the TEM image of ZNTs formed using carbon nanocoils as a template (Figure 6.7c). Clearly, formed ZNTs had a helical structure, reflecting the shape of the nanocoils. Polymeric material has also been used as a template for instance polyacrylonitrile (PAN) fibers produced by electrospinning. The resulting ZNTs are shown in Figure 6.8. The PAN fibers can either be woven or non-woven and hence, the resulting ZNTs can also be in a form of loose powder or a mat since they replicate the structure of the electrospun fibers.
Ammoxidation: Synthesis of Acrylonitrile from Ammonia and Propylene
Published in Alvin B. Stiles, Theodore A. Koch, Catalyst Manufacture, 2019
Alvin B. Stiles, Theodore A. Koch
Modifications can be made in many respects. For example, nickel can be added along with the iron as a cocomponent of the catalyst. Other types of Ludox can also be used, including even a smaller size than the 80-A Ludox SM. A higher or lower proportion of the Ludox can be used, and titania can beneficially be substituted for some or all of the silica. Zirconia from zirconium nitrate or colloidal zirconia also can be employed beneficially.
Extraction Behaviour of Tris(2-methylbutyl) Phosphate with Fission Products and Heavy Metal Ions
Published in Solvent Extraction and Ion Exchange, 2020
Subramee Sarkar, A. Suresh, N. Sivaraman
TBP obtained from Alfa Aesar Ltd., the UK was used for experiments. T2MBP was synthesized by the condensation reaction between POCl3 and stoichiometric equivalent of 2-methyl-1-butanol in the presence of pyridine, using n-heptane as the solvent. Further details on the synthesis, purification, and characterization of T2MBP are reported elsewhere.[22,30] Analytical grade diluent, n-DD was obtained from Sigma-Aldrich Ltd., USA. Nuclear grade uranyl nitrate hexahydrate and zirconium metal were received from Nuclear Fuel Complex, Hyderabad. The Zr was then converted into zirconium nitrate solution (Zr(NO3)4) based on the procedure reported elsewhere.[31] Ruthenium nitrosyl nitrate solution as RuNO(III) (Aurora Matthey Limited) and nitrates of trivalent lanthanides (Aldrich) were used without any further treatment. 99Tc (Cerca-lea, France) was supplied in the form of ammonium pertechnetate. It was completely converted into pertechnetate based on the procedure adopted elsewhere.[32] All other reagents used for the experiment were either AR or GR grade.