Improvement in photocatalysts and photocatalytic reactors for water and wastewater treatment: A review

During recent years, many advanced oxidation techniques have been investigated for water and wastewater treatment to overcome the shortage of clean water. This review summarizes the background and principles of photocatalysis applied as an advanced oxidation technology. In particular, this paper focuses on modification of photocatalysts with various dopants as well as the novel photocatalytic reactors to improve the oxidation efficiency of the pollutants in water and wastewater

Thin film nanocomposite forward osmosis membrane prepared by graphene oxide embedded PSf substrate

One of the limiting factors in good performance of forward osmosis (FO) membranes is the internal concentration polarization (ICP). To reduce ICP, thin film nanocomposite forward osmosis (TFN-FO) membranes were fabricated by adding different amounts of graphene oxide (GO) nanoplates (0-1 wt. %) to polymer matrix of polysulfone (PSf) substrate. The prepared nanocomposite membranes exhibited both hydrophilicity and porosity higher than that of neat PSf counterpart. An optimum amount of 0.5 wt% was obtained for GO addition into the membranes. The corresponding fabricated thin film nanocomposite (TFN) membrane (TFNG0.5) revealed a water permeability of 2.44 L/m2hbar which is 66% higher compared to an in-house made composite membrane. The FO performance of TFN was assessed by DI water as feed solution and 1 M NaCl as draw solution in AL-DS orientation. The water flux of the synthesized FO membranes increased upon adding of GO nanoplates and reached to a maximum water flux of 37.74 (L/m2h) for TFNG0.5 membrane. This flux is about 3 times higher than TFC membranes without significant changes in their salt rejection. The higher water flux of the TFN membranes can be attributed to ICP decrease originating from reduction of structural parameter of the membranes

Characterization and Kinetic study of PAH–degrading Sphingopyxis ummariensis bacteria isolated from a petrochemical wastewater treatment plant

The expansion of a microbial bank for the degradation of polycyclic aromatic hydrocarbons (PAHs) is crucial for removal of these persistent pollutants. In this study, five gram-negative, aerobic, non-fermentative bacterial strains (III-R3, IV-P11, IV-P13, IV-R13, and V-P18) were isolated from the activated sludge of a petrochemical wastewater treatment plant using enrichment pro­ tocol based on phenanthrene. The isolates were capable of utilizing phenanthrene, anthracene, and pyrene as a sole carbon and energy source in an aerobic batch aqueous system. The PAHs biodegradation yields were evaluated by gas chromatography and the bacterial isolates were identified using the 16S rRNA sequencing method. A first-order kinetic model provided the best fit to the phenanthrene degradation profiles with a correlation coefficient value of 0.95-0.98. The phenanthrene biodegradation rate constants and half-lives were measured at the range 0.653--Q.878 day-' and 0.79-1.06 day, respectively. Lower values of Anthracene degradation re­ sulted with the isolates of the current study, while a relatively high percentage of the removal of Pyrene was obtained by some of the isolates. The data obtained in this study shows that bacterial isolates have degradation preference over Mycobacterium sp. and Pseudomonas aeruginosa; and they are comparable with Pseudomonas stutzeri, Sphingomonas sp., and microbial consortium applied by other researchers. Analysis of the 16S rDNA gene sequence, when compared with the GenBank, indicates that all the strains belong to the genus Sphingopyxis with the nearest type strain being Sphingopyxis ummariensis Ul2 (MTCC 8591T). It is the first time that Sphingopyxis ummariensis is reported for its capability in the degradation of PAHs

Growth kinetics and Pho84 phosphate transporter activity of Saccharomyces cerevisiae under phosphate-limited conditions

The effect of phosphate (P ( i )) concentration on the growth behavior of Saccharomyces cerevisiae strain CEN.PK113-5D in phosphate-limited batch and chemostat cultures was studied. The range of dilution rates used in the present study was 0.08-0.45 h(-1). The batch growth of yeast cells followed Monod relationship, but growth of the cells in phosphate-limited chemostat showed change in growth kinetics with increasing dilution rates. The difference in growth kinetics of the yeast cells in phosphate-limited chemostat for dilution rates below and above approximately 0.2 h(-1) has been discussed in terms of the batch growth kinetic data and the change in the metabolic activity of the yeast cells. Immunological detection of a C-terminally myc epitope-tagged Pho84 fusion protein indicated derepressive expression of the Pho84 high-affinity P ( i ) transporter in the entire range of dilution rates employed in this study. Phosphate transport activity mediated by Pho84 transporter was highest at very low dilution rates, i.e. 0.08-0.1 h(-1), corresponding to conditions in which the amount of synthesized Pho84 was at its maximum

Visible light driven nanoparticle for degradation of organic dye in aqueous solution

Ohne deutschsprachige Kataloge und auch sonst sehr lückenhafte Linkliste: http://bibliologiemedievale.wordpress.com/catalogues Verlinkt ist u.a. ein Katalog von Emil Hirsch, in dem https://archive.org/stream/valuablemanuscri00emilrich#page/8/mode/2up ich die Chicagoer Seifrit-Handschrift (früher Schloß Podgora bei Görz/Gorizia, Bibliothek der Grafen von Attems) fand: http://www.handschriftencensus.de/464