Effects of inorganic nitrogen (NH₄Cl) and biodegradable organic carbon (CH₃COONa) additions on a pilot-scale seawater biofilter.

Biofilters degrade a small fraction of the natural organic matter (NOM) contained in seawater which is the leading cause of biofouling in downstream processes. This work studies the effects of chemical additions on NOM biodegradation by biofilters. In this work, biofiltration of seawater with an empty bed contact time (EBCT) of 6 min and a hydraulic loading rate of 10 mh(-1) reduces the biological oxygen demand (BOD7) by 8%, the dissolved organic carbon (DOC) by 6% and the UV absorbance at 254 nm (A₂₅₄) by 7%.

Improvement of the analysis of the biochemical oxygen demand (BOD) of Mediterranean seawater by seeding control.

Biochemical oxygen demand (BOD) is a useful parameter for assessing the biodegradability of dissolved organic matter in water. At the same time, this parameter is used to evaluate the efficiency with which certain processes remove biodegradable natural organic matter (NOM). However, the values of BOD in seawater are very low (around 2 mgO(2)L(-1)) and the methods used for its analysis are poorly developed.

Synthesis and theoretical study of a series of dipalladium(I) complexes containing the Pd2(mu-CO)2 core.

The complex [PBu4]2[Pd2(mu-CO)2Cl4] has been prepared in high yields by carbonylation of [PBu4]2[Pd2Cl6]. Methanol, potassium acetate, or CO readily reacted under ambient conditions to quantitatively afford a series of dipalladium(I) complexes, namely [Pd2(mu-CO)2Cl3(OCH3)]2-, [Pd2(mu-CO)2Cl3(OC(O)CH3)]2-, [Pd2(mu-CO)2Cl3(CO)]-, and [Pd2(mu-CO)2Cl2(OCH3)(CO)]-, all of which have the Pd2(mu-CO)2 core preserved. All these complexes have been characterized by infrared and NMR spectroscopies; the high nu(CO) stretching wavenumbers observed and the diamagnetic character of these complexes prompted us to perform theoretical calculations to describe the electronic structure of the Pd2(mu-CO)2 core and to gain an intimate description of the Pd-CO bonds.

Study of catalyzed ozonation for advanced treatment of pulp and paper mill effluents.

Ozonation and catalytic ozonation (TOCCATA process) were used as tertiary treatments of wastewaters from three different pulp and paper mills. Laboratory batch experiments were conducted to assess the efficiency of each oxidation system for removal of organic matter. The investigations measured ozone consumption rate, variations in chemical oxygen demand (COD), total organic carbon (TOC), suspended solids (SS) and molecular weight distribution with contact time.