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Abstract

This study was aimed at testing the possibility of using a biotrickling filter for the treatment of waste air resulting from animal farming. For this purpose, a laboratory and pilot biotrickling filter with a moving bed were constructed. In the first case, the removal of ammonia emissions from waste air, by means of ammonia nitrogen utilization by present micro-organisms under laboratory conditions, was tested. The mass load of the biotrickling filter was gradually increased by slowly increasing the ammonia concentration. In the second case, the pilot biotrickling filter with a moving bed was installed inside a pig farm and it was tested under real operation conditions. In the first case, the highest value of the laboratory biotrickling filter’s elimination capacity was 6.2 gNH3 m−3 of filling h−1. The elimination capacity of the pilot filter was 1.6 gNH3 m−3 of filling h−1. The source of carbon for the present micro-organisms was a 1% sucrose solution, which simulated waste water with high content of CODCR. [

elimination of ammonia. The final tetra- pyrrol closure produces the uroporphyrinogen I [1—4], The hydroxymethylbilane can be converted into the macrocyclic ring of uroporphyrinogen III by the uroporphyrinogen III synthase (isomerase; EC 4.2.1.75). This enzyme flips the ring D producing an asymetric arrangement and yielding the physiological intermediate after tetrapyrrole closure [1, 5]. PBG-deaminase has been isolated and purified from several sources, including bacteria, algae and animals ([6] and ref. therein [7—10]), however a sim­ ple purification method for

preferential elimination of chloro­ form on reaction of 2 with nucleophilic reagents is in contrast to the reported elimination of ammonia on reaction of ß-amino-/?-trifluoromethylmethylene- malononitrile with hydrazine14. An investigation of the exact mechanism of these reactions aiming to find an explaination of these facts is being now undertaken. 8 3 5-Amino-3-phenyl-4-phenylazopyrazole (12) re­ acted with 2 in refluxing pyridine to yield the expected 5-aminopyrazolo[l,5-a]pyrimidine deriva­ tive (13). On the other hand, from reaction of 12 with 2 in acetic acid

enzymatic elimination of ammonia from histidine and phenylalanine. Angew. Chem. Int. Ed. 44 , 3668 –3688. Ryle , M.J. and Seefeldt, L.C. ( 1996 ). Elucidation of a MgATP signal transduction pathway in the nitrogenase iron protein: formation of a conformation resembling the MgATP-bound state by protein engineering. Biochemistry 35 , 4766 –4775. Scherf , U. and Buckel, W. ( 1993 ). Purification and properties of an iron-sulfur and FAD-containing 4-hydroxybutyryl-CoA dehydratase/vinylacetyl-CoA delta 3-delta 2-isomerase from Clostridium aminobutyricum . Eur. J. Biochem

) 789. 6 A. W. Dox, Org. Syntheses (Collective), Vol. I. Wiley, New York, 2nd Edn. ' A. Strecker, Annalen 103 (1857) 328. 8 A. Pinner, "Die Imidoäther und ihre Derivate", Berlin, 1892, p. 102. 3* 36 Mansel Davies and A. E. Parsons Fig. 1. Infra-red spectrum acetamidine in the regions 3700—2700 cm.-1 and 1700-400 cm.-1 Fig. 2. Infra-red spectrum of solid acetamidine hydrochloride in the regions 3700-2700 cm.-1 and 1700-400 cm.-1 Infra-Red Spectrum and Structure of Acetamidine 37 with elimination of ammonia. However, its molecular weight was determined by the freezing

-quinuclidine. The adducts are usually formed by direct reaction of preformed nitrogen triiodide-1-ammonia with excess of N-base in aqueous suspension, ammonia being set free. The new adduct, then, results as a black precipitate. In the case of quinuclidine, no such reaction takes place (4); apparently the consumption of energy for elimination of ammonia and enlargement of the distances of the sheets of NI4 tetrahedra is greater than the profit of energy for adding quinuclidine. A convenient way of preparation has now been found with the aid of non- aqueous solvents

aromatic aldehyde 2 for the formation of alkene 7 , through Lewis acid sites (Cu + ) which are coordinated to the oxygen of the aldehyde, and activates it for the nucleophilic attack by 6-aminouracil. The subsequent Michael-type addition of urea ( 3 ) to alkene 7 , followed by cyclization and elimination of ammonia, gives product 4 ( Scheme 2 ). Scheme 2: Proposed mechanism for the CuI NPs catalyzed synthesis of compounds 4a-j. 3 Conclusion Copper(I) iodide nanoparticles were found to catalyze the three-component reaction of 6-aminouracils, aromatic aldehydes and

increases under certain circumstances such as high protein diet, diabetes, etc.; the urea cycle functions like a regulatory mechanism, increasing its activity and consequently maintaining the intracellular ammonia at a normal level. By this mechanism the cell protects itself from the toxic effect of ammonia accumulation. There are two main mechanisms for the elimination of ammonia: the urea cycle and the for- mation of glutamine via glutamate dehydrogenase and glutamine synthetase. The urea cycle is inhibited in thio- acetamide-treated rats, and there is consequently an

/Universities Collaborative Research Grants Scheme are thanked for support of this work. References Ballantine, J. Α., Purnell, J. H., Rayanakorn, M., Williams, K. J., Thomas, J. M.: Organic reactions catalysed by sheet silicates: Intermolecular elimination of ammonia from primary amines. J. Mol. Catal. 30 (1985) 373-388. Ballantine, J. Α., Purnell, J. H., Thomas, J. M.: Sheet silicates: Broad spectrum catalysts for organic synthesis. J. Mol. Catal. 27 (1984) 157-167. Crystal structure of triethylenediamine dihydrochloride 217 Gilmore, C. J.: MITHRIL — an integrated direct

-base equilibrium as a function of pH, 276 K, 10-2 m threonine; g(average) = 2.005. The gross spectral changes with pH clearly demon­ strate the elimination of ammonia from an a-hy- droxyalkyl radical of threonine. The observations may be described by the overall reaction (6). CH3-C(OH)-CH(COOH)NH3+ -* 3b NH4+ + CH3-C O -CH -CO O H (6) 8 The increase in signal intensity of radicals 8 was steepest between pH 1.5 and 2.0, that is around three pH units below the pH range of the steepest increase of radicals 7 from serine. From this large difference it became suspicious that