A novel bacterium, Gordonia alkanivorans strain 1B, was isolated from hydrocarbon-contaminated soil. Assessment of the biodegradation of distinct organic sulfur-compounds, such as dibenzothiophene (DBT), benzothiophene (BT), DBT sulfone, and alkylated tiophenic compounds, as the sole source of sulfur was investigated. G. alkanivorans strain 1B was able to remove selectively the sulfur from DBT while keeping intact the remaining carbon-carbon structure. Orthophenyl phenol (2-hydroxybiphenyl) was the only detected metabolic product. The bacterial desulfurization activity was repressed by sulfate. G. alkanivorans strain 1B consumed 310 microM DBT after 120 h of cultivation, corresponding to a specific desulfurization rate of 1.03 micromol/(g of dry cells x h). When an equimolar mixture of DBT/BT was used as a source of sulfur in the growth medium, G. alkanivorans strain 1B assimilated both compounds in a sequential manner, with BT as the preferred source of sulfur. Only when BT concentration was decreased to a very low level was DBT utilized as the source of sulfur for bacterial growth. The specific desulfurization overall rates of BT and DBT obtained were 0.954 and 0.813 micromol/(g of dry cells x h), respectively. The newly isolated G. alkanivorans strain 1B has good potential for application in the biodesulfurization of fossil fuels.

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Sustainable water management must nowadays consider alternative water sources and the use of reclaimed water is a good candidate. Low-pressure ceramic membrane filtration is an emerging option for safe water reclamation given its high mechanical and chemical robustness with safety and operational advantages. One-year pilot studies of hybrid coagulation-ceramic filtration were developed in Portugal in two wastewater treatment plants in the Lisbon metropolitan area. The results obtained demonstrated the technology's effectiveness, reliability and efficiency towards water quality, with the hybrid process consistently producing water highly clarified (monthly median <0.1 NTU), bacteria-free and with reduced organic matter content, regardless of the strong and severe variations in its intake.

Projection to Latent Structures (PLS) regression, a generalization of multiple linear regression, is used to model two datasets (40 observed data points each) of adsorption removal of three pharmaceutical compounds (PhCs), of different therapeutic classes and physical–chemical properties (carbamazepine, diclofenac, and sulfamethoxazole), from six real secondary effluents collected from wastewater treatment plants onto different powdered activated carbons (PACs). For the PLS regression, 25 descriptors were considered: 7 descriptors related to the PhCs properties, 10 descriptors related to the wastewaters properties (8 related to the organic matrix and 2 to the inorganic matrix), and 8 descriptors related to the PACs properties. This modelling approach showed good descriptive capability, showing that hydrophobic PhC-PAC interactions play the major role in the adsorption process, with the solvation energy and log Kow being the most suitable descriptors. The results also stress the importance of the competition effects of water dissolved organic matter (DOM), namely of its slightly hydrophobic compounds impacting the adsorption capacity or its charged hydrophilic compounds impacting the short-term adsorption, while the water inorganic matrix only appears to impact PAC adsorption capacity and not the short-term adsorption. For the pool of PACs tested, the results point to the BET area as a good descriptor of the PAC capacity, while the short-term adsorption kinetics appears to be better related to its supermicropore volume and density. The improvement in these PAC properties should be regarded as a way of refining their performance. The correlations obtained, involving the impact of water, PhC and PAC-related descriptors, show the existence of complex interactions that a univariate analysis is not sufficient to describe.

This paper addresses the enhanced removal of pharmaceutical compounds (PhCs), a family of contaminants of emerging concern, and effluent organic matter (EfOM) in water reclamation by powdered activated carbon/coagulation/ceramic microfiltration (PAC/cMF). Four chemically diverse PhCs are targeted: ibuprofen (IBP), carbamazepine (CBZ), sulfamethoxazole (SMX) and atenolol (ATN). Pilot assays (100 L/(m 2 h), 10 mg Fe/L) run with PhC-spiked sand-filtered secondary effluent and 15 mg/L PAC dosed in-line or to a 15-min contactor. They showed no PAC-driven membrane fouling and +15 to +18% added removal with PAC contactor, reaching significant removals of CBZ and ATN (59%-60%), SMX (50%), colour (48%), A254 (35%) and dissolved organic carbon (DOC, 28%). Earlier long-term demo tests with the same pilot proved PAC/cMF to consistently produce highly clarified (monthly median < 0.1 NTU) and bacteria-free water, regardless of the severe variations in its intake. A detailed cost analysis points to total production costs of 0.21 €/m 3 for 50,000 m 3 /day and 20 years membrane lifespan, mainly associated to equipment/membranes replacement, capital and reagents.