3 research outputs found
Dendrimer-Based Demulsifiers for Polymer Flooding Oil-in-Water Emulsions
Two
polyamidoamine-based dendritic molecules, named here as benzyl-G3
and octyl-G3, were synthesized using H<sub>2</sub>NCH<sub>2</sub>CH<sub>2</sub>NRCH<sub>2</sub>CH<sub>2</sub>NH<sub>2</sub> (where R is either
rigid benzyl or flexible octyl hydrophobic tails that are linked to
the central nitrogen atom). With consideration of factors, such as
the settling time, demulsifier dosage, temperature, oil content, and
kinds of surfactants, the synthesized molecules were systematically
investigated as demulsifiers for breaking up polymer flooding oil-in-water
emulsions. In comparison to traditional G3 polyamidoamine, both benzyl-G3
and octyl-G3 exhibited better demulsification efficiencies with a
dosage of 200 mg/L at a relatively low temperature (30 °C) in
short periods of time (40 min) and reached 99.3 and 99.8% oil removal
rates as they were added to the low oil-containing emulsion (1500
mg/L), respectively. A series of measurement methods were then adopted
to explore the demulsification mechanism of the two demulsifiers.
The interfacial tension and ζ potential measurements indicated
that the high demulsification efficiency of the two dendrimers could
be due to electrostatic charge neutralization. Moreover, the dendrimers
and surfactants showed strong interactions according to the turbidity
measurements, the results of which demonstrated that the hydrophobic
tails located at the center of the dendrimers also influenced the
demulsification efficiency
Nitrogen-Rich Salts Based on the Energetic [Monoaquabis(<i>N</i>,<i>N</i>‑bis(1<i>H</i>‑tetrazol-5-yl)amine)-zinc(II)] Anion: A Promising Design in the Development of New Energetic Materials
Nitrogen-rich energetic salts involving
various cations (lithium, <b>1</b>; ammonium, <b>2</b>; hydrazinium, <b>3</b>; hydroxylammonium, <b>4</b>;
guanidinium, <b>5</b>; aminoguanidinium, <b>6</b>; diaminoguanidinium, <b>7</b>; and triaminoguanidinium, <b>8</b>) based on nitrogen-rich
anion [ZnÂ(BTA)<sub>2</sub>(H<sub>2</sub>O)]<sup>2–</sup> (N%
= 65.37, BTA = <i>N</i>,<i>N</i>-bisÂ[1<i>H</i>-tetrazol-5-yl]Âamine anion) were synthesized with a simple
method. The crystal structures of all compounds except <b>1</b>, <b>2</b>, and <b>6</b> were determined by single-crystal
X-ray diffraction and fully characterized by elemental analysis and
FT-IR spectroscopy. The thermal stabilities were investigated by differential
scanning calorimetry (DSC). The DSC results show that all compounds
exhibit high thermal stabilities (decomposition temperature >200
°C). Additionally, the heats of formation were calculated on
the basis of the experimental constant-volume energies of combustion
measured by using bomb calorimetry. Lastly, the sensitivities toward
impact and friction were assessed according to Bundesamt für
Materialforschung (BAM) standard methods
Nitrogen-Rich Salts Based on the Energetic [Monoaquabis(<i>N</i>,<i>N</i>‑bis(1<i>H</i>‑tetrazol-5-yl)amine)-zinc(II)] Anion: A Promising Design in the Development of New Energetic Materials
Nitrogen-rich energetic salts involving
various cations (lithium, <b>1</b>; ammonium, <b>2</b>; hydrazinium, <b>3</b>; hydroxylammonium, <b>4</b>;
guanidinium, <b>5</b>; aminoguanidinium, <b>6</b>; diaminoguanidinium, <b>7</b>; and triaminoguanidinium, <b>8</b>) based on nitrogen-rich
anion [ZnÂ(BTA)<sub>2</sub>(H<sub>2</sub>O)]<sup>2–</sup> (N%
= 65.37, BTA = <i>N</i>,<i>N</i>-bisÂ[1<i>H</i>-tetrazol-5-yl]Âamine anion) were synthesized with a simple
method. The crystal structures of all compounds except <b>1</b>, <b>2</b>, and <b>6</b> were determined by single-crystal
X-ray diffraction and fully characterized by elemental analysis and
FT-IR spectroscopy. The thermal stabilities were investigated by differential
scanning calorimetry (DSC). The DSC results show that all compounds
exhibit high thermal stabilities (decomposition temperature >200
°C). Additionally, the heats of formation were calculated on
the basis of the experimental constant-volume energies of combustion
measured by using bomb calorimetry. Lastly, the sensitivities toward
impact and friction were assessed according to Bundesamt für
Materialforschung (BAM) standard methods