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The Fischer-Tropsch process produces liquid fuels. However, the process also yields Fischer-Tropsch wastewater, an acidic and corrosive byproduct enriched with various water-soluble oxygen-containing compounds such as alcohols, aldehydes, ketones and carboxylic acids, demanding careful treatment before discharge. Herein, the interactions between n-butanol and propionic acid, two main components in Fischer-Tropsch wastewater, and humic acid (HA) were studied with nuclear magnetic resonance (NMR) techniques. One-dimensional 1H chemical shift titration and 1H relaxation time measurements showed that: the peak width of both n-butanol and propionic acid broadened with increasing HA concentration, while the 1H chemical shift was unaltered for n-butanol, but moved to high field for propionic acid. The 1H spin-lattice and spin-spin relaxation time of n-butanol and propionic acid decreased and the 1H correlation time increased with increasing HA concentration. The interactions between HA and n-butanol were enhanced by increasing the HA concentration, but less affected by solution pH. While, the interactions between HA (20 mg/mL) and propionic acid were promoted by increasing the HA concentration and decreasing the solution pH value. It also appeared that the HA concentration plays a decisive role in the interaction. The study demonstrated that using HA for treatment of Fischer-Tropsch wastewater has a great potential in industrial applications owing to its simplicity and low price.

Three product mixtures of anthracene catalytic hydrogenation under different catalytic conditions were analyzed by nuclear magnetic resonance (NMR) spectroscopy. Dihydroanthracene, tetrahydroanthracene, symmetric octahydroanthracene, and asymmetric octahydroanthracene were successfully detected with diffusion-ordered spectroscopy (DOSY) and one-dimension selective gradient total correlation spectroscopy (selTOCSY) techniques. The 1H and 13C NMR signals of dihydroanthracene, tetrahydroanthracene and symmetric octahydroanthracene were assigned by 1H NMR, 13C NMR, DEPT135, 1H-1H COSY, 1H-13C HSQC. The conversion of anthracene and selectivity of the products were calculated by quantitative 1H NMR (QNMR). The results demonstrated that NMR is a versatile and powerful tool to guide and optimize catalytic reaction conditions for increasing the selectivity of symmetrical octahydroanthracene. The present research provides a systematic NMR analysis scheme for polycyclic aromatic hydrocarbons catalytic hydrogenation.