Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
Center for Environmental Implications of Nano Technology (CEINT), Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.
Environ Sci Technol. 2021 Jan 19;55(2):1231-1241. doi: 10.1021/acs.est.0c05470. Epub 2021 Jan 6.
Technologies for removal of mercury from produced water and hydrocarbon phases are desired by oil and gas production facilities, oil refineries, and petrochemical plants. Herein, we synthesize and demonstrate the efficacy of an amphiphilic, thiol-abundant (11.8 wt % S, as thiol) polymer nanogel that can remove environmentally relevant mercury species from both produced water and the liquid hydrocarbon. The nanogel disperses in both aqueous and hydrocarbon phases. It has a high sorption affinity for dissolved Hg(II) complexes and Hg-dissolved organic matter complexes found in produced water and elemental (Hg) and soluble Hg-alkyl thiol species found in hydrocarbons. X-ray absorption spectroscopy analysis indicates that the sorbed mercury is transformed to a surface-bound Hg(SR) species in both water and hydrocarbon regardless of its initial speciation. The nanogel had high affinity to native mercury species present in real produced water (>99.5% removal) and in natural gas condensate (>85% removal) samples, removing majority of the mercury species using only a 50 mg L applied dose. This thiolated amphiphilic polymeric nanogel has significant potential to remove environmentally relevant mercury species from both water and hydrocarbon at low applied doses, outperforming reported sorbents like sulfur-impregnated activated carbons because of the mass of accessible thiol groups in the nanogel.
从采出水和烃相去除汞的技术是石油和天然气生产设施、炼油厂和石化工厂所需要的。在此，我们合成并证明了一种两亲性、富含硫醇（11.8wt% S，作为硫醇）的聚合物纳米凝胶的功效，该纳米凝胶可以从采出水和液态烃中去除与环境相关的汞物种。纳米凝胶在水相和烃相都有很好的分散性。它对采出水中溶解的 Hg(II)配合物和 Hg-溶解的有机物配合物以及烃中元素汞（Hg）和可溶性 Hg-烷基硫醇配合物具有高的吸附亲和力。X 射线吸收光谱分析表明，无论初始形态如何，吸附的汞都在水和烃中转化为表面结合的 Hg(SR)物种。纳米凝胶对天然存在于实际采出水中的汞（>99.5%去除）和天然气凝析油（>85%去除）样品中的汞具有很高的亲和力，仅使用 50mg/L 的应用剂量就可以去除大部分汞物种。这种巯基化两亲聚合物纳米凝胶在低应用剂量下具有从水和烃中去除与环境相关的汞物种的巨大潜力，优于报道的吸附剂，如载硫活性炭，因为纳米凝胶中具有大量可利用的巯基。
