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A system that combines fermentative and photosynthetic bacteria makes combined organic wastewater treatment and energy recycling possible. This study introduces a method to separates useful byproduct, such as volatile fatty acids, to serve as the substrate for a serial photobioreactor from the outlet of anaerobic hydrogen fermentation reactor using a ceramic membrane system. Batch experiments were applied to investigate the metabolic characteristics of Rhodopseudomonas palustris WP3-5 under various conditions during photobioreactor operation. The results indicate that a higher temperature (35 °C) improved poly-β-hydroxybutyric acid (PHB) content and hydrogen accumulation. Maximal hydrogen accumulation and reduced PHB synthesis occurred at lower temperature (25 °C) at an initial pH of 6.8.. Glutamate and peptone were more suitable nitrogen sources for hydrogen production than glutamine and NH4Cl. Photohydrogen production results, using various anaerobic fermentation effluents with a dilution ratio of 0.4X, illustrated that an increased photohydrogen production rate (HPR) could be obtained using an anaerobic fermentation influent with an initial C/N ratio of 4. The result obtained when an anaerobic hydrogen fermentation reactor was connected to the serial photobioreactor showed that when the anaerobic hydrogen fermentation reactor outlet dilution increased from 2.5- to 5-fold, HPR increased. The HPR of the three bioreactors in the serial photobioreactor were 269.2, 345.6 and 256.7 mL-H2/L-reactor/day. A UV-sterilizer, which was placed between the fermentation reactor and photobioreactor, resulted in the longer (336 h) operating duration.

A novel flow injection ion chromatograph (FI-IC) system has been developed to fully automate pretreatment procedures for multi-elemental analysis of trace metals in seawater by inductively coupled plasma mass spectrometer (ICPMS). By combining 10-port, 2 position and 3-way valves in the FI-IC manifold, the system effectively increase sample throughput by simultaneously processing three seawater samples online for: sample loading, injection, buffering, preconcentration, matrix removal, metal elution, and sample collection. Forty-two seawater samples can be continuously processed without any manual handing. Each sample pretreatment takes about 10 min by consuming 25 mL of seawater and producing 5 mL of processed concentrated samples for multi-elemental offline analysis by ICPMS. The offline analysis improve analytical precision and significantly increase total numbers of isotopes determined by ICPMS, which include the metals Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Ti, V, and Zn. The blank value and detection limits of trace metals using the system with ICPMS analysis all range from 0.1 to 10 parts per trillion (ppt), except Al, Fe, and Zn. The accuracy of the pretreatment system was validated by measuring open-ocean and coastal reference seawater, NASS-5 and CASS-4. Using the system with ICPMS analysis, we have obtained reliable trace metal concentrations in the water columns of the South China Sea. Possessing the features of full automation, high throughput, low blank, and low reagent volume used, the system automates and simplifies rigorous and complicated pretreatment procedures for multi-elemental analysis of trace metals in seawater and effectively enhances analytical capacity for trace metal analysis in environmental and seawater samples.