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Available online xxxxCombustion, pyrolysis and hydropyrolysis reactivity of Tuncbilek lignite was monitored by temperature programmed pyrolysis (TPP) under pure nitrogen flow, temperature programmed oxidation (TPO) under air flow and temperature programmed hydrogenation (TPH) under hydrogen flow at atmospheric pressure in a packed bed reactor.The structures of the organic and inorganic components were analyzed by NMR spectroscopy and XRD. Only methane and hydrogen were the main products of TPP while small amounts of CO and CO 2 were also observed. Solid-state 1 H and 13 C CPMAS and 1 H liquid Nuclear Magnetic Resonance (NMR) Spectroscopy of the pristine lignite, as well as tar and char products of pyrolysis and hydrogenation (hydropyrolysis), revealed similar tar compositions. TGA of pyrolysis chars indicated that there were more residual volatiles in hydropyrolysis char in comparison to pyrolysis char. Elemental analysis of pyrolysis and hydropyrolysis chars revealed that 25% of sulfur was lost during pyrolysis, whereas N 90% of sulfur was lost during hydropyrolysis indicating efficiency of atmospheric pressure hydropyrolysis for both desulfurization and tar production. Volatile matter and fixed carbon, mostly aromatic, gave rise to distinct oxidation peaks during TPO. The oxidation peak due to volatiles was missing from TPO of pyrolysis char as well as from organic contents determined by NMR spectroscopy.

The bipolar membrane electrodialysis (BMED) system has been receiving intense attention recently due to its simultaneous desalination and acid and base production. In this study, in addition to salt water recovery, the BMED system was used for the generation of hydrochloric acid (HCl), ammonia (NH 3 •H 2 O), and sodium hydroxide (NaOH) from a binary salt mixture of 1.12 M ammonium chloride (NH 4 Cl) and 0.51 M sodium chloride (NaCl) solutions. The main aim of the study is to evaluate the effects of type and concentration of anolyte and/or catholyte solutions (electrolytes) on desalination, feed solution conductivity, acid and base formation from salt, and product purity. Sulfuric acid (H 2 SO 4 ), sodium sulfate (Na 2 SO 4 ), NaCl, and NaOH are used as the electrolytes, and three different concentrations (0.05, 0.075, 0.1 M) were tested for all types of electrolytes. The results of the study indicate that 0.05 M H 2 SO 4 is the most effective electrolyte with respect to the desalination and product (acid and base)-based conversion. Higher concentrations of electrolytes result in higher process performance as well as lower product impurity.

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