皮革专用染料生产技术

介绍了皮革专用染料的生产新技术。此面技术是以邻氨基苯磺酸，三聚氟氢，碳酸钠等为原料，经过重氮化，偶合，缩合，盐析，干燥等于工艺过程，生产出新型活性染料。此种染料可替代进口染料，不仅可以染皮革，也可以染棉织口 。     

Uptake of Reactive Black 5 by pumice and walnut activated carbon: Chemistry and adsorption mechanisms

The potential of using pumice and walnut wood activated carbon as low-cost adsorbents for the removal of the diazo dye Reactive Black 5 (RB5) from aqueous solutions was investigated. The Langmuir isotherm fit to the data specified the presence of two different natures of adsorption sites with different binding energies on the AC-W surface. Kinetic modelling showed that the adsorption behaviour and mechanism of RB5 for both adsorbents is believed to happen via surface adsorption followed by diffusion into the pores of the AC-W and pumice. The main adsorption mechanisms are hydrogen bonding, electrostatic bonding and n–π interactions.     

Novel azobenzene precursors for NLO active polyuretanes: Synthesis, quantum chemical and experimental characterization

For the development of electro optical active polyurethanes six new derivatives of 2-{(2-hydroxyethyl)-[4-(4-nitrophenylazo)phenyl]amino}ethanol and two of 2-{(2-hydroxyethyl)-[4-(5-nitropyridin-2-ylazo)phenyl]amino}ethanol were synthesized by azocoupling reaction. Molecular geometry, hyperpolarizability β_FF and ground state dipole moment μ_g were acquired by RHF ab initio (6–31G**) calculations using HyperChem software package. To characterize NLO performance of synthesized azo compounds second order non linear coefficients d₃₁ and d₃₃ were measured as function of chromophore load in guest–host films (PMMA). Eight synthesized compounds can be grouped in four similar gross formula pairs (different position of octyloxy group) with almost equal μ_g β_FF product and different μ_g values. At low chromophore concentrations higher dipole moment compounds perform better. Lower dipole moment compounds have better NLO efficiency at high chromophore loads. Accurate ranking of all chromophores, based on two-level model corrected zero frequency d₃₃(0) values, was not viable due to overestimation of the dispersion factor.     

Preparation and characterization of surface bond-conjugated TiO2/SiO2 and photocatalysis for azo dyes

Surface bond-conjugated TiO₂/SiO₂ was prepared by means of the impregnation method. Based on the results of XRD, FTIR, XPS and BET measurements, the growth of titania (predominantly anatase) on the silica substrate seems to occur by anchoring of the TiO₂ phase through Ti–O–Si cross-linking bonds. The structure model of TiO₂/SiO₂ was proposed. Compared to B–TiO₂, the most efficient catalyst is 30 wt.% TiO₂/SiO₂ (Ims30), which showed three times higher photoactivity for the degradation of reactive 15 (R15). In addition, the catalyst had a higher photoactivity on a silica of smaller particle size than on the silica of larger particles. Silica gel plays the basic role of dispersion and support for power TiO₂. The isoelectric point of the catalyst was 3.0 pH units by the measurement of zeta-potential, indicating the presence of the surface acidity of the catalyst. The photodegradation and the adsorption of R15 and cationic blue X-GRL (CBX) were investigated with the change of initial aqueous pH.     

Decolorizing and detoxifying textile wastewater, containing both soluble and insoluble dyes, in a full scale combined anaerobic/aerobic system

The wastewater originating from the bleaching and dyeing processes in the textile factory Ten Cate Protect in Nijverdal (the Netherlands) was successfully treated in a sequential anaerobic/aerobic system. In the system, a combination of an anaerobic 70-m3 fluidized bed reactor and a 450-m3 aerobic basin with integrated tilted plate settlers, 80-95% of the color was removed. The color was largely removed in the preacidification basin and the anaerobic reactor. Color, deriving from both reactive as well as disperse, was anaerobically removed, indicating that these type of dyes were reduced to colorless products. Interestingly, the vat dyes, the anthraquinones and indigoids, which were thought to be removed mainly aerobically, were largely anaerobically decolorized. Apparently the anaerobic system is capable of effectively removing the color of both soluble as insoluble dyes. The treated effluent of the sequential anaerobic/aerobic treatment showed no toxicity towards the bioluminescent bacterium Vibrio fisheri (EC20 (95%) > 45%). Partially bypassing the anaerobic stage resulted in increased toxicity (EC20 (95%) of 9% and 14%) in the effluent of the aerobic treatment and caused significant decrease of color removal. The results of this study show a main contribution of anaerobic treatment in decolorizing and detoxifying the textile wastewater in the sequential anaerobic/aerobic system.     

Azo dye adsorption effect induced by elliptically polarized light in azo dye-doped liquid crystals

This study elucidates the azo dye adsorption effect induced by elliptically polarized light in azo dye-doped liquid crystals (ADDLCs). Experimental results reveal that the light-induced molecular reorientation that is caused by the adsorbed azo dyes declines as the absolute value of the ellipticity of the pumping beam, having a proper selectively fixed light intensity or a proper selectively fixed light component along the direction of major axis, increases. The long axes of the adsorbed dyes are found to be independent of the sign of the light ellipticity, but they do depend on the direction of the major or minor axis of the elliptically polarized light. Notably, the tilt angle in LC alignment is not observed in this experiment. Additionally, neither twist angles nor tilt angles can be induced using a circularly polarized pumping beam.     

Extended aromatic π-electron conjugated dyes with three azo bonds and either one or two azulen-1-yl moieties in molecule. Synthesis and basicity

Azo dyes with either one or two identical or different azulen-1-yl moieties attached to the structure -N₂-C₆H₄-N₂-C₆H₄-N₂- were prepared, the phenylene ring being either 1,3-1′,3′ or 1,4-1′,4′ disubstituted. The syntheses were accomplished in good yields via mono or bis diazotization of the corresponding anilines followed by the coupling with unsubstituted or alkyl substituted azulenes in acetic/acetate medium. The recorded electronic spectra of the synthesized compounds were analyzed and were compared with those of related compounds. The isosbestic points resulting from protonation of the azo compounds enabled pK_a values to be determined. From these pK_a values it is apparent that all studied compounds are very weak bases. The high solvatochromic property of the compounds with para,para-substituted phenylene groups reflects the hyperpolarizability of these compounds.     

Combined chemical and biological treatment of azo dye-containing wastewaters

Wastewaters produced in textile industrial processes contain organic dyes, such as azo dyes, which are not amenable to direct biological treatment. This work examines the possibility of combining ozonation with biological treatment for the effective treatment of wastewaters containing the azo dye Orange II. Oxalate, formate, and benzene-sulfonate are found to be the final products of ozonation. Sulfonated aromatics such as benzene-sulfonate cause organic pollution and are not readily degradable because of their xenobiotic character. For the biological treatment of the ozonation products, activated sludge acclimated to the main product (benzene-sulfonate) was used, and batch experiments under aerobic conditions were performed. On the basis of experimental data, mathematical models describing both processes were developed. An overall mathematical model describing the integrated chemical and biological treatment of the dye was used to estimate the cost of the whole process. The implications of this study for the design of effective dye-containing wastewater treatment plants are discussed.     

Rapid bending of a nonliquid crystal azobenzene polymer film and characteristics of surface relief grating

A nonliquid crystal polymer was prepared by introducing the azobenzene group into the main chain of the poly(amic acid). The polymer film can be easily prepared by a general method. The obtained film exhibits a high bending intensity and shows fast bending response and a very large bending angle (reach of 90°) at room temperature without temperature heating, which can improve the efficiency of the transformation of energy from light to mechanical energy. The surface structure of the relief grating also was investigated by atomic force microscopy. The depth of typical surface relief was approximately 65 nm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

纺织品禁用偶氮染料检测方法研究

为了实现23种禁用偶氮染料的完全分离,作者采用气相色谱—质谱联用方法,通过改进色谱条件,取得了较好的分离,同时缩短了检测时间。本试验可以看出采用气——质联用方法部分同分异构体是可以的。