Polymers Made by Inverse Vulcanization for Use as Mercury Sorbents

Abstract

Inverse vulcanization is a process in which highly abundant and low-cost elemental sulfur is copolymerized with an unsaturated organic molecule such as a polyene. This process has provided a variety of useful materials with high sulfur content—typically 50% or greater in sulfur by mass. These materials have garnered increasing interest in as sorbents for mercury, due to the high affinity of sulfur for mercury. In this review, the features of mercury sorbents made by inverse vulcanization are presented. Additionally, case studies are provided to illustrate the variety of polymer architectures accessible with this chemistry, the versatility of these materials in mercury remediation, and prospects for industrial use.

Processes for coating surfaces with a copolymer made from sulfur and dicyclopentadiene

“…29 And while a number of sorbents for mercury are known, 30–33 there still remains a need for low-cost sorbents. For this reason, polysulfides made by inverse vulcanisation have emerged as versatile materials for mercury remediation, 6,10,34–36 but there are few reports of these mercury sorbents that are generally solvent resistant. In the oil and gas sector, for instance, there are scenarios in which mercury sorbents would have to be effective in capturing mercury from mixtures of water and hydrocarbons.…”

“…And while this sorption capacity is lower than many high performance sorbents such as activated carbon and other sophisticated porous or nanostructured materials, 31,38 the sorption capacity is comparable to other sulfur polymer sorbents. 34…”

Synthesis and characterization of polysulfides formed by the inverse vulcanisation of cyclosiloxanes with sulfur

“…For 1 H, 13 C and 29 Si NMR spectroscopy, solution based samples were dissolved in CDCl 3 and recorded using a Bruker Avance 400 MHz spectrometer and all spectra were recorded in parts per million ( ppm). Tetramethylsilane (TMS) was used to calibrate and 1 H NMR and residual amounts of protium found in NMT solvents were used for reference (e.g.…”

“…Peak multiplicity is represented as follows: s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet, coupling constants in Hertz (Hz). Solid State NMR measurements were carried out on a Bruker AVANCE 300 (B 0 = 7.05 T) spectrometer operating at 300.13 and 75.46 MHz for 1 H and 13 C, respectively. A double-tuning cross-polarisation magic angle spinning (CP/MAS) probe was used with 7 mm zirconia rotors and Kel-F caps.…”

“…6 The polysulfides synthesized by these methods show properties such as, self-healing, high resistance to swelling in solvents, oils and fuels, high stability from degradation by UV and ozone, minimal structural degradation under stress, high refractive indecies, 7 the ability to transmit mid-wave infrared light, 8 high affinity for metals, 9 and enhanced capacity retention. 10 The combination of these properties have given rise to numerous applications, [11][12][13][14] including in IR sensing and imaging, 7 sorption of heavy and/or valuable metals, 5,15 batteries as Li-S cathode materials, 16 self-healing polymers, 8 functional coatings, [17][18][19] fertiliser delivery, 20,21 antibacterial surfaces, 22 insulation 23,24 and oil spill remediation. 3 Inorganic cross-linkers are relatively unexplored in the field of inverse vulcanisation.…”