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In Indonesia, the rising sugar production contributes to an increase in sugarcane bagasse waste. This waste can be used for environmental purposes, such as the treatment of colorants in the textile industry using mesoporous silica materials. Previous studies showed the potential of synthesizing mesoporous silica from agricultural waste including corn cob and rice husk. Therefore, this study aimed to investigate the potential use of sugarcane bagasse as an alternative waste source for synthesizing mesoporous silica. Sugarcane bagasse ash, containing a high silica content ranging from 55.5% to 70%, served as the main silica source for synthesis. A combination of surfactant templates, Pluronic 123 (P123), and Cetyl Trimethyl Ammonium Bromide (CTAB) in a ratio of 1:1, was used to obtain optimal structure, surface area, pore radius, and pore volume. These parameters were optimized to enhance the adsorption of colorants, specifically methyl blue commonly found in textile waste. The characterization techniques used included Small-Angle X-ray Scattering (SAXS), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) analysis, and UV-Vis spectroscopy. The synthesized mesoporous silica showed a surface area of 323.3 m2/g, a pore radius of 2.437 Å, and a pore volume of 0.52 cc/g, with an adsorption capacity of 97.3%. This adsorbent product was expected to provide a cost-effective, eco-friendly source of silica suitable for various dye adsorption applications and the treatment of heavy metals in industrial waste.

In Indonesia, the rising sugar production contributes to an increase in sugarcane bagasse waste. This waste can be used for environmental purposes, such as the treatment of colorants in the textile industry using mesoporous silica materials. Previous studies showed the potential of synthesizing mesoporous silica from agricultural waste including corn cob and rice husk. Therefore, this study aimed to investigate the potential use of sugarcane bagasse as an alternative waste source for synthesizing mesoporous silica. Sugarcane bagasse ash, containing a high silica content ranging from 55.5% to 70%, served as the main silica source for synthesis. A combination of surfactant templates, Pluronic 123 (P123), and Cetyl Trimethyl Ammonium Bromide (CTAB) in a ratio of 1:1, was used to obtain optimal structure, surface area, pore radius, and pore volume. These parameters were optimized to enhance the adsorption of colorants, specifically methyl blue commonly found in textile waste. The characterization techniques used included Small-Angle X-ray Scattering (SAXS), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) analysis, and UV-Vis spectroscopy. The synthesized mesoporous silica showed a surface area of 323.3 m2/g, a pore radius of 2.437 Å, and a pore volume of 0.52 cc/g, with an adsorption capacity of 97.3%. This adsorbent product was expected to provide a cost-effective, ecofriendly source of silica suitable for various dye adsorption applications and the treatment of heavy metals in industrial waste. [ABSTRACT FROM AUTHOR]

Organic colorants of textiles found in the female burial of Lieto Ristinpelto, SW Finland, were analyzed by HPLC-PDA. The textiles’ visible colors varied from different brownish shades to blueish, greenish, and reddish hues. The aim of the chromatographic analysis was to deepen the current understandings of the dyes used in Finland at the transition between the 12th and 13th centuries AD, i.e., at the beginning of the local Medieval period, and to contribute important new information about dyes and clothing from this less-known period of textile history of Finland. The textile finds consisted of a bronze spiral ornamented shawl, an apron tied at the waist, two tablet-woven bands, and a diagonally plaited band with plaited tassels. A unique find was a textile possibly made using the sprang technique. Other textile finds were an orange wool tabby and twill fragments. Analysis of thirty samples from fourteen different textiles indicated that woad colorants were present in most samples, accompanied with lichen compounds, and dyer’s madder was in two visually orange fragments. The visually reddish samples contained luteolin, but no red colorants.

Organic colorants of textiles found in the female burial of Lieto Ristinpelto, SW Finland, were analyzed by HPLC-PDA. The textiles' visible colors varied from different brownish shades to blueish, greenish, and reddish hues. The aim of the chromatographic analysis was to deepen the current understandings of the dyes used in Finland at the transition between the 12th and 13th centuries AD, i.e., at the beginning of the local Medieval period, and to contribute important new information about dyes and clothing from this less-known period of textile history of Finland. The textile finds consisted of a bronze spiral ornamented shawl, an apron tied at the waist, two tablet-woven bands, and a diagonally plaited band with plaited tassels. A unique find was a textile possibly made using the sprang technique. Other textile finds were an orange wool tabby and twill fragments. Analysis of thirty samples from fourteen different textiles indicated that woad colorants were present in most samples, accompanied with lichen compounds, and dyer's madder was in two visually orange fragments. The visually reddish samples contained luteolin, but no red colorants. [ABSTRACT FROM AUTHOR]

The present work reports decisive new data regarding the characterization of the paint materials used by Cypriot icon painters in Orthodox icons from the 12th to the 18th century. Eight samples of red paint, collected from seven different icons originally placed in three different churches in Morphou and Nicosia (Cyprus) have been analysed to identify the painting technique. The identification of pigments and fillers was performed using micro-Raman spectroscopy and Fourier Transform Infrared spectroscopy (FT-IR). In order to determine the binding medium, Pyrolysis Gas Chromatography-Mass Spectrometry (Py/GC/MS) and Gas Chromatography-Mass Spectrometry (GC/MS) were used. The study of the organic colorants was performed by Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) analysis. Both inorganic pigments and organic colorants were used to create the red hues in the icons. Cinnabar was identified in almost all the paint samples studied, although in some cases red lead was also found. European cochineal, kermes, redwood and Indian lac were identified in the red paints, in combination with inorganic pigments. Moreover, stratigraphic analyses allowed us to assess that animal glue and calcium sulphate were used for the preparation layers, while egg was used as binding medium in the red paint layers. The identification of Indian lac in a 12th century icon is the first known occurrence reported in the literature of this organic colorant in the European tradition. [ABSTRACT FROM AUTHOR]

Since its introduction in the cultural heritage field, nearly 30 years ago, surface-enhanced Raman spectroscopy (SERS) has emerged as a promising analytical technique that is particularly suitable for the detection and identification of organic colorants. Its great molecular selectivity and specificity, and unparalleled sensitivity compared to other instrumental methods, have allowed researchers to successfully characterize a wide number of natural dyes and a few synthetic ones in microscopic samples from objects of artistic, historical, and archaeological significance. Continued research over the course of the past decade has led to the construction of comprehensive databases of dyes, whose adsorption and spectral properties have been investigated at length; to the comparative study of the efficiency and performance of various metal substrates; and to the evaluation of several sample treatment methods and ad-hoc analytical protocols. In addition, recent literature in the field of SERS for art and archaeology has described instrumentation and technique advancements aimed at solving the unique challenges posed by the analysis of irreplaceable objects, namely, quasi non-destructive sampling, spatial resolution improvement, examination of insoluble compounds, and resolution of dye mixtures. Reviewing the most salient methodological and technological milestones that have traced the history of SERS for cultural heritage to date, the present article is intended as a practical resource for those researchers who would like to undertake systematic characterization of organic colorants from artworks using this powerful technique. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A dye is a colored substance used to impart permanent color to other substances. Its most important use is in coloring textile fibers and fabrics. The removal of colour from dyehouse waste waters is currently a major problem in the textile sector. This paper provides an overview of the treatment technologies that can currently be used by the textile processor and the developments over the past decade with respect to the toxicological and ecotoxicological properties of synthetic organic dyes.

Materials that come in contact with foods are potential sources of chemical food contamination. Consequently, characterization of their composition is of paramount importance considering the possible occurrence of several unknown molecules such as non-intentionally added substance (NIAS), residual monomers, degradation products, plastic additives and organic colorants. Previous studies concerning the characterization in terms of composition are focalized in the recognition of additives. To the best author's knowledge there are no scientific data about the composition of a plastic material in terms of colorants. In this work, an analytical method employing capillary ultra high-performance liquid chromatography and electrospray ionization quadrupole orbitrap high-resolution mass spectrometry (UHPLC–ESI Q-orbitrap) was exploited for characterization of polycarbonate for food contact material. Data-dependent experiments for targeted and untargeted analysis were employed after a total dissolution of polycarbonate samples and extraction of its components. The presence of common additives such as antioxidants and UV absorbers was confirmed by targeted analysis, while, the untargeted approach combined with the high mass accuracy of orbitrap technology allowed to identify for the first time some polycarbonate degradation products and the organic dyes effectively used for the coloration of plastic objects intended to come in contact with food. The present study shows the high potential of this technique in the field of material characterization aimed at food safety evaluation. [ABSTRACT FROM AUTHOR]

In research and in actual conservation practice, conservators have to choose adequate methodologies for carrying out treatments successfully, while respecting the integrity of artworks. Besides the knowledge of the authentic materials present in each artwork, conservators must be able to choose appropriate conservation materials and methods. Solvents are widely used in cleaning, but solubility issues are also of high importance in consolidation treatments as well as in protective coating applications. The central aim of this work is to critically re-assess the potential of Hansen solubility parameters (HSPs) for a reliable use in the field of artwork conservation. An effort was made to develop an efficient methodology for critical solvent selection (CSS). For this purpose, two different methods were used for the estimation of various artwork conservation materials. A group-contribution method (GC), based on the chemical composition of materials, was applied for the prediction of HSPs of egg yolk, pine resin and seven red organic colorants (Mexican, Polish and Armenian cochineal, kermes, madder, lac dye and dragon's blood), traditionally used in paintings, textiles and illuminated manuscripts. Additionally, an experimental set up was used for testing the solubility of the commercial products of synthetic conservation materials, Primal AC-532K, Beva gel 371 a and b (old and new formula) and a commercial matt varnish made of dammar and wax. With the direct use of Hansen solubility parameters and the relative energy difference (RED) between various materials it was made possible to carry out ad hoc “virtual” solubility tests that may apply to real and complex systems such as cultural heritage artworks. [ABSTRACT FROM AUTHOR]

The paper covers some aspects regarding theory and practice in the teaching of organic colorants to chemical engineering students. There is little in the world of education that is more depressing than bad university teaching. Intellectual development is a product of both internal and external processes. In the paper are presented the importance of teaching and learning, the conditions of learning, and some methods of evaluation, all specific to teaching the subject in question. [ABSTRACT FROM AUTHOR]

Abstract: In the present article an attempt is made to elucidate the organic colorants commonly encountered in the Russian avant-garde painting palette by a combined art historical, documentary and physicochemical investigation, and to examine the influence of environmental factors on the chromatic profile originally sought by the artist. The overall approach based on written sources is confirmed by measurements on relevant paintings. The documentary research deals with the influences of Orthodox iconography, folkloric art, and occidental modernist tendencies on the Russian avant-garde palette, and studies the effects of contradictory historical processes in the chromatic profile of individual paintings. In the experimental section a series of colorants are investigated concerning the effects of accelerated ageing on experimental painting tables, prepared as watercolor and gouache layers on paper ground. The resulting samples are subjected to colorimetric and spectroscopic measurements, and analogous analytical procedures are applied on samples taken from selected paintings. A systematic comparative study of all data permits evaluation of the materials used in terms of their stability towards extrinsic factors, and proposal of degradation routes in order to assist museum curators and conservators in every concrete case related to the broad spectrum of pigments examined. [Copyright &y& Elsevier]