COD equivalences

In the same way as the specific BOD5 of a number of different organic compounds is established (see Table 6), the COD equivalence of reducing inorganic compounds can be measured (see Table 5). These tables should be considered as mere guidelines due to possible vagaries in sampling and actual procedure conditions,... 

The HC particularly involve COD equivalences that are fairly dependent on handling conditions and BOD5 equivalences that are even more difficult to pin down (see paragraph... 

COD provides i measure of the oxygen equivalent to that portion of the organic mtitter in i sample that is susceptible to oxidation by a strong chemical oxidant. A higher level of COD can be degraded (neutralized) chemically. The le el of COD. however, automatically reduces with the level of BOD and no further treatment is normally necessary. 

An experimental nm had been conducted to study the effect of airflow rate in the 3 litres aeration wastewater treatment tank. Nutrients were added in the treatment tank to ensure sufficient bacterial growth. In each experiment, the cell optical density, COD and die concentration of chemicals equivalent to carbohydrates were monitored for the duration of aeration. 

A catalyst supported on y-AFO was prepared from Re2Pt(CO)i2l (Fig. 70) and characterized by IR. X-ray photoelectron spectroscopy (XPS), and TPR. The chemi.sorbed cluster was treated with H2 at about 150 C resulting in fragmentation and formation of rhenium subcarbonyls at 400 C the sample was completely decarbonylated. A catalyst prepared from a mixture of Re3(//-H)3(CO)i2l and PtMe2(// -cod)] and treated under equivalent conditions showed the rhenium to... 

Thus, the decomposition of Ni(COD)2 by dihydrogen in the presence of HDA yields nanoparticles, the aspect ratio of which depends upon the ligand concentration. Thus for one or less equivalent HDA, the reaction produces isotropic Ni particles whereas using ten equivalent HDA, nanorods, monodis-perse in diameter, are obtained [74]. The formation of nanowires can also be promoted by a rapid decomposition process. This is illustrated by the decom-... 

Markovnikov addition [162]. The catalyst precursor is a cationic complex, [Rh(cod)2] BF4, used in the presence of 2 equiv. of PPhj. An equivalent amount of the hydrogenated vinylarene is formed (Eq. 4.38) [163-165]. 

A.464 A purple-black, mixed-valence Ir11 Ir1 binuclear compound, [(Ir(cod)(/u-L) 2]BF4 (L = pz, 4-Mepz), is synthesized from the reaction of [Ir(cod)(//-L)]2 with NOBF4. The binuclear cationic radical exhibits an EPR spectrum showing hyperflne coupling to two equivalent Ir. Cyclic voltammetry studies have shown a reversible, one-electron oxidation.4... 

Tri-ra-butylphosphite, tri-ra-butylarsine, and tri-ra-butylstibine complexes of platinum(O) have been prepared by the reaction of the ligand with pt(COD)2] or, in the case of the phosphite, by reaction with [Pt(PPh3)4].38 All form four-coordinate complexes when 4 mole-equivalents of ligand are used, but when 2 or 3 mole-equivalents of the phosphite ligand are used, mixtures of three- and four-coordinate complexes are observed.38... 

Intermolecular hydroamination of 1-alkynes with anilines has recently been performed using [Rh(COD)2]+ in combination with three equivalents of tricyclohexylphosphine (1.5 mol. % catalyst) at 50 °C to yield the corresponding imines (Equation (16)) 172... 

The complex [Rh(COD)L L2]+, where L1 = PPh3 and L2 = pyridine, and a neutral benzoate complex, Rh(COD)(PPh3)(OCOPh), also effect highly selective hydrogenation of 1-alkynes to 1-alkenes as well as reduction of 1-alkenes and ketones to alcohols (139) the one equivalent of base required may be related to monohydride formation [Eq. (25)]. The bisphosphine complexes also catalyze reduction of styrene oxide to 2-phenylethanol and phenylacetaldehyde (140) ... 

James and coworkers found that one benzylamine is actually bound to the rhodium in the active catalyst in hydrogenations of PhCH=NRCH2Ph using [Rh(COD)(PPh3)2]PF6 as catalyst precursor. However, the addition of more than two equivalents of benzylamine inhibited the catalysis [63]. 

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