Manufacture Of Dyes Research Articles

Exploring of Bacterial Pigments from Thamirabarani River Alluvial Soil: Harnessing their Versatility in Dye and Paint Manufacturing

Color is a fundamental aspect of human life, playing a vital role in culture and industry. The paints and coatings industry, a significant sector within global manufacturing, has seen increased scrutiny due to its environmental and health impacts. Conventional paints contain harmful chemicals like volatile organic compounds (VOCs) and solvents, which pose risks to both workers and the environment. Recent shifts towards natural and bio-based pigments, particularly those derived from microorganisms, offer a promising alternative. Microbial pigments, such as those produced by chromogenic bacteria, provide eco-friendly, non-toxic colorants with additional benefits like antioxidant and antimicrobial properties. This review highlights the potential of bacterial pigments in various applications, particularly in the textile industry as natural dyes, and discusses their role in reducing the environmental footprint of synthetic pigments. The study also emphasizes the importance of further research into improving the production and stability of these bio- pigments for broader commercial use in industries such as food, cosmetics, and pharmaceuticals.

Discovery of the 1-naphthylamine biodegradation pathway reveals a broad-substrate-spectrum enzyme catalyzing 1-naphthylamine glutamylation.

1-Naphthylamine (1NA), which is harmful to human and aquatic animals, has been used widely in the manufacturing of dyes, pesticides, and rubber antioxidants. Nevertheless, little is known about its environmental behavior and no bacteria have been reported to use it as the growth substrate. Herein, we describe a pathway for 1NA degradation in the isolate Pseudomonas sp. strain JS3066, determine the structure and mechanism of the enzyme NpaA1 that catalyzes the initial reaction, and reveal how the pathway evolved. From genetic and enzymatic analysis, a five gene-cluster encoding a dioxygenase system was determined to be responsible for the initial steps in 1NA degradation through glutamylation of 1NA. The γ-glutamylated 1NA was subsequently oxidized to 1,2-dihydroxynaphthalene which was further degraded by the well-established pathway of naphthalene degradation via catechol. A glutamine synthetase-like (GS-like) enzyme (NpaA1) initiates 1NA glutamylation, and this enzyme exhibits a broad substrate selectivity toward a variety of anilines and naphthylamine derivatives. Structural analysis revealed that the aromatic residues in the 1NA entry tunnel and the V201 site in the large substrate-binding pocket significantly influence NpaA1's substrate preferences. The findings enhance understanding of degrading polycyclic aromatic amines, and will also enable the application of bioremediation at naphthylamine contaminated sites.

Recent trends in medicinal applications of mercury based organometallic and coordination compounds

Abstract Metal-based drugs are finding new medical applications, particularly in antibacterial therapies. Compounds such as Prontosil and ciprofloxacin, as well as its derivatives such as beta-lactam drugs, aminoglycosides, vancomycin, fosfomycin, as well as tetracyclines, play critical roles in the prevention of bacterial and fungal infections. The increasing prevalence of microbial resistance is prompting the use of metal complexes to tackle fungal and bacterial strains. Mercury-based complexes, which are known for their unusual characteristics and reactivity, have received a lot of interest in the field of medicine recently. Additionally, Schiff base complexes are widely used as antifungal, antibacterial, and anticancer drugs, as well as in dye manufacturing. This article discusses current advances in the use of mercury compounds for combating fungus and bacteria, offering information on their efficacy and future applications.

Utilizing traditional knowledge and creatively repurposing mining waste to develop new sustainable products geared toward eco-friendly construction

Mining is a very important activity for civil engineering. Important aggregates are removed from this for civil construction, bridges and roads, development of construction materials and several other applications. However, this activity has negatively impacted both the exploration areas and their surroundings. Associated with this environmental concern, it is possible to enter the context of real estate paints, which emit considerable amounts of volatile organic compounds that harm the atmosphere and the health of workers and users, in addition to reducing the air quality of the environment in which they are located was applied. Furthermore, with technological advances, industrial paints with synthetic pigments began to replace natural products, causing environmental pollution. The volatile organic compounds generated by real estate paints have resulted in health problems for the population. The literature has reported a growing search for renewable paint products, such as environmentally friendly paints and other environmentally friendly products for use in construction. In this way, materials from mining waste have been studied as an alternative for the development of ecological bricks. Studies suggest that mining waste, considered an environmental liability, can be an alternative for the production of soil-cement bricks that meet technical and environmental specifications. In addition to ecological bricks, another aspect that has emerged as a viable alternative for using mining waste is the production of ecological paints and the application of possible natural pigments to diversify the colors of ecological paints. Finally, the manufacture of ecological paints, natural dyes, ecological bricks and cement from mining waste, in addition to being an environmental improvement alternative, can be used in socio-environmental projects, allowing social inclusion, teaching and reproducing environmental education, and increasing environmental awareness. In this review we address the main types of mining waste that are used in the production of bricks and paints ecological.

Understanding the Hazards of Hexane and Short-Term Exposure to Air Contaminated with Hexane Affects the Nervous System and can Cause Dizziness

Abstract: The term ‘hydrocarbon’ is self-explanatory which means compounds of carbon and hydrogen only. Hydrocarbons play a key role in our daily life. You must be familiar with the terms ‘LPG’ and ‘CNG’ used as fuels. LPG is the abbreviated form of liquified petroleum gas whereas CNG stands for compressed natural gas. Another term ‘LNG’ (liquified natural gas) is also in news these days. This is also a fuel and is obtained by liquifaction of natural gas. Petrol, diesel and kerosene oil are obtained by the fractional distillation of petroleum found under the earth’s crust. Coal gas is obtained by the destructive distillation of coal. Natural gas is found in upper strata during drilling of oil wells. The gas after compression is known as compressed natural gas. LPG is used as a domestic fuel with the least pollution. Kerosene oil is also used as a domestic fuel but it causes some pollution. Automobiles need fuels like petrol, diesel and CNG. Petrol and CNG operated automobiles cause less pollution. All these fuels contain mixture of hydrocarbons, which are sources of energy. Hydrocarbons are also used for the manufacture of polymers like polythene, polypropene, polystyrene etc. Higher hydrocarbons are used as solvents for paints. They are also used as the starting materials for manufacture of many dyes and drugs. Thus, you can well understand the importance of hydrocarbons in your daily life. In this unit, you will learn more about hydrocarbons

Surfactant-modified coconut coir powder (SMCCP) as a low-cost adsorbent for the treatment of dye-contaminated wastewater: parameters and adsorption mechanism.

The dye-contaminated wastewater discharged from various industries such as dye manufacturing, paint, textile, paper, and cosmetic is a prime source of surface water pollution having serious detrimental effects on both the environment and human beings. These hazardous dyes when exposed to water obstruct the penetration of sunlight into the water and thus restrain aquatic plants from generating photosynthetic compounds. Moreover, some dyes are potential cancer-causing and also negatively impact the human nervous and respiratory systems. In this current study, modification of coconut coir powder (CCP) was carried out through cationic surfactant treatment and was successively utilized as the adsorbent for decoloring anionic dye (acid blue 185 (AB 185)) containing waste stream. Further, a comparative investigation of the dye removal efficiency of raw CCP and surfactant-modified coconut coir powder (SMCCP) as the adsorbent was studied. On surfactant treatment, using a very minimal SMCCP dosage of 8.3g/L, a very high percentage dye removal of 98.4% is possible, whereas with raw CCP, even after using a higher dosage of 14g/L, only 70.1% dye removal can be achieved. Characterization of SMCCP adsorbent was done by Fourier transform infrared, thermogravimetric, X-ray, and scanning electron microscope analyses. Furthermore, the optimization of critical operating parameters was investigated for the effective adsorption of AB 185 dye in batch mode. The adsorption of AB 185 onto SMCCP was a thermodynamically spontaneous endothermic process, following the Langmuir isotherm and pseudo-second-order kinetic model. Moreover, regeneration of exhausted SMCCP by 0.1 (M) NaOH was achieved with a satisfactorily high recovery of 97% in the first cycle. Subsequently, SMCCP can be successfully reutilized for five consecutive cycles with a loss of 17.6% in the total adsorption capacity. With all such advantages, the present study delivers a new paradigm to utilize the novel adsorbent SMCCP as a promising eco-friendly adsorbent aided by its advantage of regeneration and reusability for the treatment of dye-contaminated wastewater.

Selective adsorption and removal of Congo red dye from waste water using catechol-stabilized reusable palladium nanoparticles

Several industries including textile, dye manufacturing industries, paper and pulp industries discharge colored wastewater. The majority of synthetic dyes is composed of toxic azo compounds. Eradication of toxic azo dyes, organic pollutants, radioactive materials from the global ecosystem has received remarkable attention due to their detrimental effects on human health and ecosystem. Nanotechnology-based applications on catalytic degradation of contaminants from aqueous ecosystem have evolved as a major topic of research in the scientific community, to develop a cost-effective and energy-effective strategy. In this context, nanomaterials have gained much attention because of its unique physico-chemical properties. Herein, catechol-generated palladium nanoparticles (PdNPs) have been utilized for the selective removal of congo red dye from wastewater. In this study, Palladium nanocatalyst (4 μg/ml) developed earlier by our group, was screened for degradation of dyes of different nature. The newly developed nanocatalyst was found to be effective against anionic dyes. Among the anaionic dyes, congo red was selected for degdradation study in detail. Complete degradation of congo red dye (CR) (150 μM) is found to happen within 10 min. Besides catalytic degradation, the efficiency of the recycled catalyst was evaluated, which exhibits 60 % efficiency even after the 3rd cycle. Gas chromatography-mass spectrometry (GC–MS) characterization of the degraded products reveals the formation of benzidine, indicating the reductive cleavage of azo linkage of the dye.In summary, the results highlight the potential development of a nanocatalyst for the selective and efficient removal of congo red, suggesting a simple,cost-effective, and reusable approach to prevent industrial pollutant in aqueous ecosystem.

New Canary Islands Roman mediated settlement hypothesis deduced from coalescence ages of curated maternal indigenous lineages

Numerous genetic studies have contributed to reconstructing the human history of the Canary Islands population. The recent use of new ancient DNA targeted enrichment and next-generation sequencing techniques on new Canary Islands samples have greatly improved these molecular results. However, the bulk of the available data is still provided by the classic mitochondrial DNA phylogenetic and phylogeographic studies carried out on the indigenous, historical, and extant human populations of the Canary Islands. In the present study, making use of all the accumulated mitochondrial information, the existence of DNA contamination and archaeological sample misidentification in those samples is evidenced. Following a thorough review of these cases, the new phylogeographic analysis revealed the existence of a heterogeneous indigenous Canarian population, asymmetrically distributed across the various islands, which most likely descended from a unique mainland settlement. These new results and new proposed coalescent ages are compatible with a Roman-mediated arrival driven by the exploitation of the purple dye manufacture in the Canary Islands.

Synthesis of Pharmaceutically Relevant Arylamines Enabled by a Nitroreductase from Bacillus tequilensis.

Arylamines are essential building blocks for the manufacture of valuable pharmaceuticals, pigments and dyes. However, their current industrial production involves the use of chemocatalytic procedures with a significant environmental impact. As a result, flavin-dependent nitroreductases (NRs) have received increasing attention as sustainable catalysts for more ecofriendly synthesis of arylamines. In this study, we assessed a novel NR from Bacillus tequilensis, named BtNR, for the synthesis of pharmaceutically relevant arylamines, including valuable synthons used in the manufacture of blockbuster drugs such as vismodegib, sonidegib, linezolid and sildenafil. After optimizing the enzymatic reaction conditions, high conversion of nitroaromatics to arylamines (up to 97 %) and good product yields (up to 56 %) were achieved. Our results indicate that BtNR has a broad substrate scope, including bulky nitro benzenes, nitro pyrazoles and nitro pyridines. Hence, BtNR is an interesting biocatalyst for the synthesis of pharmaceutically relevant amine-functionalized aromatics, providing an attractive alternative to traditional chemical synthesis methodologies.

Use Of Natural Dyes From Plants In Coloring Woven Yarns

The use of natural dyes as an environmentally friendly alternative to reduce the use of synthetic dyes which have a negative impact on the environment. Natural dyes can be obtained from various natural sources such as plants, animal waste, and minerals, with plants being the most common source. Plant pigments such as anthocyanins, tannins, flavonoids, and chlorophyll provide a variety of colors that can be used for coloring. The natural dyeing process involves four stages: making the dye solution, fabric preparation, dyeing, and fixation. Testing the quality of natural dyes includes color visualization tests, color aging, color differences and fastness to washing. The methodology for writing this article is a literature study, reviewing various related research from 2013 to 2023. The results show that several plants such as Tarum, Coconut, Secang, Noni, Turmeric, and Shallots can produce colors such as dark blue, brownish cream, red , yellow, and brownish orange on fabric. In conclusion, natural dyes not only support environmental sustainability but also offer a safe and low-cost coloring alternative, although there are challenges in the manufacturing and application process of these natural dyes.

Manufacturing of isocyanate-based oligomeric dyes with high coloring capabilities: synthesis and application in the dyeing of organic chrome-free leather

Leather dyeing is a critical step in leather manufacturing, as it is responsible for providing leather products with an eye-catching visual aspect and adequate quality properties to meet customers' expectations. This step is becoming more and more challenging as the leather industry advances hand in hand with new environmentally friendly policies and regulations to achieve a safer and healthier planet by replacing the highly polluting Cr-based leather tanning technology with greener alternatives. As a result, achieving high-performance dyeing of organic chrome-free leather is one of the bottlenecks for the sustainable development of the leather industry. Herein, we propose a novel strategy to fabricate an isocyanate-based oligomeric dye (IBD) with high coloring capabilities (component content higher than 62.8%) based on toluene 2,4-diisocyanate and reactive red dye 180. This material has been tested for the dyeing of biomass-derived aldehyde (BDA)-tanned leather with excellent outcomes. The experimental results showed that the crust leather dyed with our novel IBD dyeing agent had higher color fastness and better fullness than the leather dyed with conventional anionic (CAD) or reactive red 180 (RRD-180) dyes. These excellent and promising results open new avenues in manufacturing high-performance organic Cr-free leather products and help to ensure the sustainable transition of the leather industry from Cr-based leather tanning to more sustainable alternatives, maintaining the final quality of the leather products.Graphical abstract

Carotenoids: Overview of the main methods and conditions of their preparation

Carotenoids represent a group of isoprenoid pigments whose high biological activity is not limited to their provitamin properties. Due to their ability to participate in redox reactions, carotenes are increasingly considered as promising compounds in the prevention and correction of cardiovascular and neurodegenerative disorders, as well as in oncology and the treatment of various other diseases. Carotenoids are widely used in the manufacture of food additives and dyes, feed for aquaculture, farm animals and poultry, as well as in so-called nutraceuticals and cosmetics. When formulating optimal feeding rations, vitamin A nutrition is often considered separately due to its vital role in normal growth, development, maintenance and reproduction. The main precursor of vitamin A is β-carotene, which naturally enters the body exclusively via vegetable-based provender. However, since the carotene contained in plant raw materials is an unstable compound, the use of feed additives containing β-carotene becomes relevant. In industry, carotenoids can be produced either by chemical or biological synthesis. However, the majority of carotenoids – 80–90% – are obtained by chemical synthesis. At the same time, public demand for sustainable production dictates the need to find alternative approaches for obtaining this valuable commodity. The article provides an overview of the main biotechnological methods for the production of carotenes using various microorganisms, including microalgae, bacteria and fungi, as well as analysing the effect of culture conditions on the yield of target pigments.

Facile synthesis of carbon supported ternary nickel-cobalt-iron nanocatalyst for the hydrodechlorination of 2-chlorophenol

Introduction: Chlorophenols (CPs) have become prevalent in the manufacture of herbicides, fungicides, pesticides, insecticides, pharmaceuticals, and dyes, contributing significantly to water pollution. Addressing this challenge, various treatment methods such as incineration, electrochemistry, photochemistry, biotechnology, and catalytic hydrodechlorination have been explored to reduce toxic chlorophenol contaminants. Hydrodechlorination stands out as an efficient technique for the removal of chlorine atoms. The dispersion of metal nanoparticles on supported materials significantly enhances the catalytic activity by increasing the specific surface area. Among these, carbon-supported nickel-cobalt-iron nanoparticles emerge as promising catalysts for the hydrodechlorination of 2-chlorophenol. Method: This study employs a chemical reduction method at high temperatures under an inert gas atmosphere to synthesize carbon-supported ternary nickel-cobalt-iron nanocatalysts, aiming to detoxify soil and water from pesticide residues. The physicochemical properties of these nanocatalysts were characterized using energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Their catalytic activity was assessed through gas chromatography with a flame ionization detector (FID). Results: The analysis revealed that metallic nanoparticles are uniformly dispersed on the carbon support, with particle sizes ranging from 10 to 60 nm and an average size of 30 nm. The hydrodechlorination (HDC) of 2-chlorophenol (2-CP) achieved satisfactory conversions under various reaction conditions. Conclusion: The carbon-supported nickel-cobalt-iron nanoparticles demonstrated effective catalytic activity for the hydrodechlorination of 2-chlorophenol, highlighting their potential for application in the treatment of chloroorganic contaminations in the future.

Adsorption of Chromium (VI) from Aqueous Solution Using Nano TiO2 Doped Strong Base Anion Exchange Resin

Background: The evolution of environmentally-safe methods for treating hazardous chemicals in wastewater, particularly urban and industrial wastewater, has increased interest over recent years. The chromium-containing wastewater is produced by industries from steel, metallurgical, electroplating, chemical, refractory, leather tanning, dye manufacturing, mining, cementing, textiles, etc. Consequently, advanced techniques are essential for treating chromium-polluted water. Objective: The prime objective of this effort was to assess the adsorption performance of nanoTiO2 (nanoparticles of average crystallite size 19.15 nm) doped strong base anion exchange resin (TDTulsion) for Cr(VI)to that of the host Tulsion A-62 (MP). Methods: The tests were carried out in batches in the temperature-controlled water bath shaking unit, with 30 ml of the aqueous solution containing Cr(VI) and a certain amount of resin being stirred for 6 hours at 303 K. Using a standard diphenylcarbazide (DPC) procedure at 540 nm, the solution was spectrophotometrically analyzed for Cr(VI). Results: The majority of the Cr(VI) ions are adsorbed by the anion exchange resins Tulsion A- 62(MP), and TD-Tulsion is in the pH range of 4.0 to 5.0. The maximal sorption capacity of Cr (VI) was established to be 181.5 and 204.8 mg/g for Tulsion A-62(MP) and TD-Tulsion, respectively. Conclusion: The TD-Tulsion has a substantially better adsorption capacity than Tulsion A-62(MP) under similar conditions. The outcomes show that modifying anion-exchange resin with nano titanium dioxide improves adsorption performance in Cr(VI) removal from drinking water and contaminated water.

Study on the Biotoxicity, Microbial Degradation and Metabolism, and Solidification of Monoaromatic Hydrocarbons (MACHs)

Monoaromatic hydrocarbons (MACHs), also known as aromatic organic compounds, are a general term for benzene and its derivatives. In a broad sense, monoaromatic hydrocarbons include all aromatic compounds. It can be used as an organic solvent in building decoration materials and is also widely used in other industries such as dye manufacturing, rubber manufacturing, pharmaceutical industry, pesticide industry, etc. Therefore, monoaromatic hydrocarbons are common pollutants emitted by human activities and can be widely detected in human living and living environments. With the development of China's urban economy, the improvement of residents' living standards, and the rapid increase in the number of motor vehicles, the pollution of monoaromatic hydrocarbons has become increasingly severe. Monoaromatic hydrocarbons have strong carcinogenic effects and can directly harm human respiratory, hematopoietic, nervous, reproductive and other system organs. Monoaromatic hydrocarbons also have high photochemical reactivity and are closely related to the formation of photochemical smog and aerosols in the atmosphere. Moreover, monoaromatic hydrocarbons have the characteristics of wide pollution sources, long action time, high pollution concentration, and long release cycle. They have been prioritized by the United States Environmental Protection Agency (USEPA) as pollutants for control, and have also been included in China's "blacklist" of environmental priority pollutants.

Vertex-edge based resolvability parameters of vanadium carbide network with an application

A big amount of vanadium is used in the industry. It is used as a vanadium carbide stabiliser in steel production. Only 0.5 % vanadium in an iron alloy will double the tensile strength. Vanadium salts are used in leather, ink, dye manufacturing and yellow ceramic glaze. On the other hand, vanadium pentoxide is used as a catalyst, in the chemical industry, for the production of sulphuric acid and in the petroleum refinery industry. Resolvability parameter is the most discussed topic in graph theory. This helps to reorganise a network in a unique way, sometimes in terms of atoms (metric dimension) and sometimes bound (edge metric dimension). We studied resolvability parameters of vanadium carbide network in this article i.e. metric, edge metric and partition dimension. Among these metrics resolvability defined by parameters taking a subset from the set of vertices, if it has a unique representation with all the vertices, then it is called a resolving set. The number of elements in the smallest resolving set is called the metric dimension. While the number of elements of the minimal subset of vertices taking from vertex set is called the edge metric dimension, if the representations are unique of all edges and the set is called the edge resolving set. This study can have an effect in many ways in the research, particularly, with the help of some key points such as network structure analysis, material science via material properties, graph theory applications, predictive modelling, material testing and characterisation, as well as in industrial applications.

A synergistic application of simultaneous electrocoagulation-electrooxidation process for the treatment of floor-wash wastewater containing Rhodamine B dye

Floor-wash wastewater (FWW) generated from dye manufacturing plants is a voluminous stream containing high colour and low COD. Such streams can be treated separately, and reused for floor-washing. In the present study, FWW containing Rhodamine B (RhB) dye was treated using a simultaneous electrocoagulation-electrooxidation (EC-EO) system with a precisely controlled energy supply to EC and EO. Compared to only EC or only EO, the EC-EO system achieved significantly greater COD and colour removal from FWW. With a total charge of 0.63 Ah/L evenly distributed between EC and EO, the colour and COD removal were ~ 100 and 94.43 %, respectively. The formation of insoluble, polymerized products in EO and their subsequent entrapment in metal hydroxide flocs formed in EC was the main pathway for RhB removal from FWW. The total energy and specific energy consumptions were: 1.66 kWh/m3 and 5.22 Wh/g-COD removed for EC-50 %¦EO-50 %; 2.82 kWh/m3 and 11.45 Wh/g-COD removed for EC-00 %¦EO-100 %; and 1.75 kWh/m3 and 40.23 Wh/g-COD removed for EC-100 %¦EO-00 %, respectively, indicating significant synergy between EC and EO processes applied simultaneously. FTIR and LC-MS analyses were performed to delineate the degradation pathway of RhB. The seed germination test was performed using treated FWW to assess toxicity. Seeds exposed to EC-EO-treated FWW had no significant adverse effect on soot and root length, while delayed seed germination was observed in seedlings exposed to raw FWW. This work presents a previously unreported mechanism of RhB removal by simultaneous EC-EO process.

A Review on the Use of Metal Oxide-Based Nanocomposites for the Remediation of Organics-Contaminated Water via Photocatalysis: Fundamentals, Bibliometric Study and Recent Advances.

The improper disposal of toxic and carcinogenic organic substances resulting from the manufacture of dyes, drugs and pesticides can contaminate aquatic environments and potable water resources and cause serious damage to animal and human health and to the ecosystem. In this sense, heterogeneous photocatalysis stand out as one effective and cost-effective water depollution technique. The use of metal oxide nanocomposites (MON), from the mixture of two or more oxides or between these oxides and other functional semiconductor materials, have gained increasing attention from researchers and industrial developers as a potential alternative to produce efficient and environmentally friendly photocatalysts for the remediation of water contamination by organic compounds. Thus, this work presents an updated review of the main advances in the use of metal oxide nanocomposites-based photocatalysts for decontamination of water polluted by these substances. A bibliometric analysis allowed to show the evolution of the importance of this research topic in the literature over the last decade. The results of the study also showed that hierarchical and heterogeneous nanostructures of metal oxides, as well as conducting polymers and carbon materials, currently stand out as the main materials for the synthesis of MON, with better photocatalysis performance in the degradation of dyes, pharmaceuticals and pesticides.

Fiberglass cloth coated by coffee ground waste-derived carbon quantum dots/titanium dioxide composite for removal of caffeine and other pharmaceuticals from water

Coffee ground waste from the coffee beverage preparation is mainly discarded and consequently ends up in landfill, which cause the contamination of caffeine in various environmental compartments. This study focuses on the upcycling of coffee-ground waste to carbon quantum dots (CQDs) for use as a modifying material to improve the visible light activity of titanium dioxide (TiO2). The CQD solution was synthesized by hydrothermal method, which has an average size of 2.80 ± 0.63 nm. The CQDs/TiO2 photocatalysts were prepared by combining CQD solutions at various amounts with sol-gel TiO2 and then coated on the fiberglass cloths (FGCs). The photocatalytic application mainly focuses on the removal of caffeine from the water. The photocatalytic experiment was preliminary run in a simple batch reactor under visible light. The 5CQDs/TiO2 coated FGC (5 mL of CQD solution/g of Ti-based on sol-gel) showed the best performance, and it was selected for the removal of caffeine and other pharmaceuticals (i.e., carbamazepine and ibuprofen) in the recirculating reactor. The removals of caffeine, carbamazepine, and ibuprofen after irradiation for 9 h were 82%, 88%, and 84%, respectively. The residual concentrations were significantly lower than the reported toxicity levels based on specific species. The changes in total organic carbon were observed, indicating the mineralization of pharmaceuticals in water. The 5CQDs/TiO2 coated FGC showed good flexible performance. No obvious loss of activity was observed for five runs. The actual wastewater from the coffee pot cleaning process was also tested. The removal was 80% for caffeine and 86% for color in the unit of the American Dye Manufacturers Institute (ADMI).

DIC offers $97 million for Seqens facility

Seqens, a French pharmaceutical services firm, says the Japanese chemical maker DIC has offered to acquire its Canadian subsidiary, PCAS Canada, for $97 million. The Canadian unit specializes in the custom manufacturing of phenolic resins, photoactive compounds, dyes, and other materials used in the production of semiconductors and printed electronics. Seqens got the Canadian facility when it acquired a controlling interest in PCAS in 2017.