Aniline blue, adsorption

In the presence of anions which are precipitated by calcium chloride solution, proceed as follows. Precipitate the acetic acid test solution with calcium chloride solution, and collect the precipitate on a filter or in a centrifuge tube. Remove the water from the precipitate either by drying or by washing with alcohol and ether. Mix a small amount of the precipitate with diphenylamine in a dry micro test-tube, add a little concentrated phosphoric acid, and heat gently over a free flame. Calcium phosphate and free oxalic acid are formed, and the latter condenses with the diphenylamine to aniline blue and colours the hot phosphoric acid blue. The colour disappears on cooling. Dissolve the melt in alcohol, when a blue colouration appears. Pour the alcoholic solution into water thus precipitating the excess of diphenylamine, which is coloured light blue by the adsorption of the dyestuff. The dye may be extracted from aqueous solution by ether. 

Molasses adsorption based on color unit scale adsorption of Aniline Blue expressed as g/g carbon ai an equilibrium solution concentration of 0.10 g/liter. 

Abridged data on such a study appear in Table 14 5. Inspection of the table discloses that the adsorption of aniline blue closely parallels the M-RE hence if the M-RE is being used nothing will be gained by adding the test with Aniline Blue. 

Wu YG, Hui L, Li X, Zhang YZ, Zhang WC (2007) Degradation of aniline in weihe riverbed sediments under denitrification conditions. J Environ Sci Health, Part A Tox Hazard Subst Environ Eng 42(4) 413-419. doi org/10.1080/10934520601187302 Yadav S, Tyagi DK, Yadav OP (2011) EquiUbrium and kinetics studies on adsorption of aniline blue from aqueous solution onto rice husk carbon. Int J Chem Res 2(3) 59-64 Yang J, Tsai FP (2001) Development of a solid-phase microextraction/reflection-absorption infrared spectroscopic method for the detection of chlorinated aromatic amines in aqueous solutions. Anal Sci 17 751-756... 

Modified electrodes for this analytical purpose have mostly been formed by electrode adsorption of the mediator systems on the electrode surface or by electropolymerization [24,116]. Recently, for example, NAD(P)H oxidations have been performed on platinum or gold electrodes modified with a monolayer of pyrroloquinoline quinone (PQQ) [117] or on poly(methylene blue)-modified electrodes with different dehydrogenases entrapped in a Nafion film for the amperometric detection of glucose, lactate, malate, or ethanol [118]. In another approach, carbon paste electrodes doped with methylene green or meldola blue together with diaphorase were used for the NADH oxidation [119]. A poly(3-methylthio-phene) conducting polymer electrode was efficient for the oxidation of NADH [120]. By electropolymerization of poly(aniline) in the presence of poly(vinylsulfonate) counterions. 

In such Pc LB films, CuPc mainly exists as dimer. When the LB films were exposed to various organic vapors, the dimer absorbance band was blue-shifted from 625 nm initially to 624 (hexane), 622 (benzene), 620 (aniline), 620 (toluene), and 619 nm (pyridine), respectively (Figure 3.2). It is clear that the change becomes apparent when the films were exposed to the vapors of aromatic compounds. When such film was continuously exposed to benzene vapors, the dimer band was blue-shifted much more (Figure 3.3). However, the Soret bands have no change in their adsorption position. In all the cases, there is a hypochromic effect when exposed to the vapors. A same phenomenon was observed in LB films of bis(phthalocyaninate) rare earth compounds exposed to hexanal vapor [32]. These changes are associated with the formation of a charge-transfer (CT) complex between the phthalocyanine and the VOC [33,34]. 

As for PANI/polysaccharide composite, PANI/extracellular composite had successfully apphed for anionic reactive dyes removal, such as reactive brilliant blue R and reactive orange 16 [25]. The electrostatic interactions between dye anions and cationic ammonium in the composite were attributed for the adsorption process with the maximum adsorption capacity of 0.5775 and 0.4748 mmol/g for reactive brilliant blue R and reactive orange 16, respectively. The effect of substituted anihne to adsorption was investigated by synthesizing several alkyl-substituted aniline/chitosan composites... 

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