Decolorization of reactive dyes, Part I: eco-friendly approach of reactive dye effluents decolorization using cationized sugarcane bagasse

2018 ◽  
Vol 47 (2) ◽  
pp. 108-115 ◽  
Author(s):  
Amal A. Aly ◽  
Safia A. Mahmoud ◽  
Morsy Ahmed El-Apasery
Keyword(s):  
Sugarcane Bagasse ◽  
Treatment Time ◽  
Reactive Dyes ◽  
Reactive Dye ◽  
Content Type ◽  
Factors Affecting ◽  
Reactive Orange ◽  
Langmuir And Freundlich Models ◽  
Reactive Red 195

Purpose This paper aims to decolorize the effluents of textile Reactive Orange 5 and Reactive Red 195 dyes by using cationized sugarcane bagasse. Design/methodology/approach Cationized sugarcane bagasse was prepared and used as an adsorbent for both reactive and hydrolyzed reactive dyes. Characterization of the sugarcane bagasse structure resulted by cationization was monitored using Fourier transform–infrared, while morphologically was detected using scanning electron microscopy and X-ray powder diffraction. Findings The maximum adsorption capacities are 805, 1,664, 1,772 and 1,596 mg/g for Hydrolyzed Red 195, Hydrolyzed Orange 5, Reactive Red 195 and Reactive Orange 5 dyes, respectively. Research limitations/implications Factors affecting the percentage of dye removal were optimized on different parameters such as adsorbent dose and treatment time. The data were discussed using the Langmuir and Freundlich Models of adsorption. Practical implications The reuse of hydrolyzed reactive dyebaths gives reasonably good fastness properties on nylon fabrics. Social implications The study has enabled the production of an eco-friendly and less expensive method of reactive dye effluent decolorization. Originality/value The study provides a potentially simple approach to decolorize dye effluents of Reactive Orange 5, Red 195 dyes and also the reuse of hydrolyzed reactive dyebaths for dyeing nylon.

Synthesis of a novel tetrakisazo navy-blue reactive dye based on DSD acid and its synergistic blackening property

2015 ◽  
Vol 44 (6) ◽  
pp. 386-391 ◽  
Author(s):  
Aiqin Gao ◽  
Hongjuan Zhang ◽  
Kongliang Xie
Keyword(s):  
Cotton Fabric ◽  
Research Work ◽  
Reactive Dyes ◽  
Reactive Dye ◽  
Original Research ◽  
Reactive Black 5 ◽  
The Novel ◽  
Fastness Properties ◽  
Content Type ◽  
Absorbance Spectra

Purpose – The purpose of this paper is to synthesise a tetrakisazo reactive dye and to characterise its dyeing property to meet the demand for better black reactive dyes. Design/methodology/approach – The novel tetrakisazo navy-blue reactive dye based on 4,4′-diaminostilbene-2,2′-disulphonic acid was designed and synthesized. The dyeing behaviour of it on cotton fabric was discussed. The synergistic blackening effect and absorbance spectra were investigated by absorbance and reflectance spectra, K/S and colorimetric data. Findings – The exhaustion and fixation of the designed reactive dye were higher than 20 per cent than those of the commercial reactive dye, CI Reactive Black 5. The novel reactive dye has complementary with Reactive Red SPB and Reactive Yellow C-5R in absorbance spectra from 360 to 700 nm. Three reactive dyes had synergistic effect in colour deepening properties. The dyed cotton fabric possessed high K/S value and low reflectance in the whole visual spectrum range from 360 to 700 nm. Practical implications – Comparison with the commercial Reactive Black DN-RN, the blackness of the dyed fabrics with the mixture dyes was greatly improved and the fastness properties on cotton fabrics were also good. Originality/value – The paper is an original research work. Because the mixture dyes had better blackness and good fastness properties, it would have wide application in the dyeing of cotton fabric.

Tenacity and colorfastness properties of chemically modified jute fibres dyed with Reactive Orange 14 and Basic Violet 14

2016 ◽  
Vol 20 (2) ◽  
pp. 102-111
Author(s):  
Md Asadul Hoque ◽  
Md Saiduzzaman ◽  
A. Nayeem Faruqui ◽  
Md Ashadul Islam
Keyword(s):  
Design Methodology ◽  
Soap Solution ◽  
Reactive Dyes ◽  
Dye Uptake ◽  
Cellulosic Fibre ◽  
Light Fastness ◽  
Content Type ◽  
Chemically Modified ◽  
Dye Absorption ◽  
Reactive Orange

Purpose This paper aims to examine the loss of tenacity and colorfastness properties of bleached and modified (acrylonitrile, AN and methacrylonitrile, MAN) jute fibres dyed with Reactive Orange 14 and Basic Violet 14. Design/methodology/approach Jute fibres dyed with Reactive Orange 14 and Basic Violet 14 were studied as a function of exposure to sunlight in air, washing with soap solution and spotting with acids and alkalis. Findings Dye absorption of Basic Violet 14 was higher compared to Reactive Orange 14 at optimum dyeing conditions. Optimum dye uptake of Reactive Orange 14 required relatively severe conditions compared to that of Basic Violet 14. Whereas, Reactive Orange 14 showed overall good colorfastness to sunlight and moderate in washing compared to Basic Violet 14. All the bleached and modified fibres showed good colorfastness to weak acids and alkalis regardless of Reactive Orange 14 and Basic Violet 14 dyes. The loss in tenacity was higher in the case of non-modified fibres, and among the modified fibres, Basic Violet 14 showed the lowest loss in tenacity in the exposure to sunlight. Originality/value Many studies have been devoted to improve the substantivity of cellulosic fibre for reactive dyes. A few efforts were made to improve the light fastness. In this work, investigation will be made on a comparative study of loss of tenacity and colorfastness properties of bleached and modified (AN and MAN) jute fibres dyed with both Reactive Orange 14 and Basic Violet 14 on exposure to sunlight, washing and acid and alkali spotting. Optimum dyeing conditions will also be investigated for economic dyeing.

Decolourisation of reactive dyes with laccase-mediator system

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bharti Rana ◽  
J.N. Chakraborty
Keyword(s):  
Treatment Time ◽  
Waste Water Treatment ◽  
Reactive Dyes ◽  
Work Activity ◽  
Preliminary Screening ◽  
Box Behnken Design ◽  
Content Type ◽  
Optimum Response ◽  
Selection Of ◽  
Natural And Synthetic

Purpose This paper aims to study the ability of laccase for decolourisation of reactive dyes in presence and absence of natural and synthetic mediators. Design/methodology/approach Box–Behnken design was used to optimize the parameters to achieve optimum response value. Preliminary screening using several mediators was performed to evaluate extent of decolourisation for the purpose followed by selection of effective mediators only. Findings Laccase performs in acidic pH; increase in temperature enhances its activity. Rate of decolourisation depends on laccase and dye concentration, temperature, pH and treatment time. Out of five mediators studied, HBT, BT and VA showed promising results. Research limitations/implications Study on decolourisation was conducted for individual dyes. In some cases, dyes are applied in combination which requires further study for authentication of data. Practical implications Decolourisation with laccase has been found to be a promising technology in waste water treatment. However, selection of mediator remains a crucial factor. Social implications Reactive dyes are self-hydrolysed over time under natural conditions and extent of decolourisation depends on concentration of dye discharged and time spent. If not decolourised quickly, it imposes restriction on use of river water for irrigation. Originality/value In this work, activity of various natural and synthetic mediators alongwith laccase was studied to achieve maximum decolourisation which was not studied earlier.

Factors affecting the spatial pattern of nitrate contamination in Texas aquifers

2019 ◽  
Vol 31 (4) ◽  
pp. 857-876
Author(s):  
Aynaz Lotfata ◽  
Shrinidhi Ambinakudige
Keyword(s):  
Nitrate Concentration ◽  
Nitrate Contamination ◽  
High Plains ◽  
Southern High Plains ◽  
Content Type ◽  
Factors Affecting ◽  
Trinity Aquifer ◽  
Well Depth ◽  
Groundwater Nitrate Contamination

Purpose The elevated level of nitrate in groundwater is a serious problem in Texas aquifers. To control and manage groundwater quality, the characterization of groundwater contamination and identification of the factors affecting the nitrate concentration of groundwater are significant. The purpose of this paper is to determine factors which have significant impacts on the elevated groundwater nitrate concentrations of the Southern High-Plains and the Edwards-Trinity aquifers. Design/methodology/approach The characterization of groundwater nitrate contamination was undertaken by analyzing the hydrochemical data of groundwater within a statistical framework. The multivariate statistical analysis (ordinary least square) and geographically weighted regression (GWR) models were used to study the relationship between groundwater nitrate contamination and land use of the study areas. Findings Results show groundwater nitrate contamination is typically due to an overapplication of N fertilizers to cotton in the Southern High-Plains aquifer and to grassland in the Edwards-Trinity aquifer. Adjusted R2 (0.45) explains variations of nitrate concentration by well-depth, cotton production, shrubland and grassland in the Edwards-Trinity aquifer. The results of an analysis of variations in N concentration with well depth for all 192 wells indicate that nitrate concentrations in water from wells in the Southern High-Plains and Edwards-Trinity aquifers tend to decrease with increasing well-depth. Originality/value In this study, the GWR model was built to identify nitrate concentration within a geographic framework to ensure sustainable use of groundwater, which is important for local management purposes. The analysis should include local spatial variations of elements such as hydrologic characteristics and the land use activities if groundwater nitrate contamination causes adverse effects on human and ecosystem health.

A feasible approach for enhancing union dyeing of wool/acrylic blend fabrics with heterobifunctional cationic reactive dyes

2019 ◽  
Vol 89 (23-24) ◽  
pp. 5085-5095 ◽  
Author(s):  
Hang Xiao ◽  
Chunhong Li ◽  
Peng Wang ◽  
Tao Zhao
Keyword(s):  
Reactive Dyes ◽  
Reactive Dye ◽  
Step Method ◽  
Factors Affecting ◽  
Cationic Group ◽  
Reactive Groups ◽  
One Step ◽  
Dyeing Method ◽  
The One ◽  
Method Factors

In this work, a facile method to enhance union dyeing with cationic reactive dyes on wool/acrylic blend fabrics was reported. Three cationic reactive dyes containing various numbers of reactive groups were synthesized and employed on wool, acrylic and wool/acrylic blend fabrics using the one-bath one-step method. Factors affecting the dye exhaustion, union dyeing and leveling properties, including dyeing pH, temperature and dye structure, were investigated. Experimental results revealed that the cationic reactive dye containing heterobifunctional reactive groups and a cationic group attached on the backbone of structure exhibited better union dyeing properties, irrespective of dyeing method. The improvement in the union dyeing on wool and acrylic fabrics followed a decreasing order: Dye 1 > Dye 3 > Dye 2. In additional, the wool/acrylic blend fabrics dyed with Dye 1 showed outstanding leveling properties. The fastness properties of wool/acrylic fabrics for all cationic reactive dyes were good to excellent.

scholarly journals Characterization of RarA, a Novel AraC Family Multidrug Resistance Regulator in Klebsiella pneumoniae

2012 ◽  
Vol 56 (8) ◽  
pp. 4450-4458 ◽  
Author(s):  
Mark Veleba ◽  
Paul G. Higgins ◽  
Gerardo Gonzalez ◽  
Harald Seifert ◽  
Thamarai Schneiders
Keyword(s):  
Multidrug Resistance ◽  
Klebsiella Pneumoniae ◽  
Efflux Pump ◽  
Content Type ◽  
Resistance Phenotype ◽  
Serratia Proteamaculans ◽  
Virulence Potential ◽  
Article Type ◽  
Acrab Efflux Pump

ABSTRACTTranscriptional regulators, such as SoxS, RamA, MarA, and Rob, which upregulate the AcrAB efflux pump, have been shown to be associated with multidrug resistance in clinically relevant Gram-negative bacteria. In addition to the multidrug resistance phenotype, these regulators have also been shown to play a role in the cellular metabolism and possibly the virulence potential of microbial cells. As such, the increased expression of these proteins is likely to cause pleiotropic phenotypes.Klebsiella pneumoniaeis a major nosocomial pathogen which can express the SoxS, MarA, Rob, and RamA proteins, and the accompanying paper shows that the increased transcription oframAis associated with tigecycline resistance (M. Veleba and T. Schneiders, Antimicrob. Agents Chemother. 56:4466–4467, 2012). Bioinformatic analyses of the availableKlebsiellagenome sequences show that an additional AraC-type regulator is encoded chromosomally. In this work, we characterize this novel AraC-type regulator, hereby called RarA (Regulator of antibiotic resistance A), which is encoded inK. pneumoniae,Enterobactersp. 638,Serratia proteamaculans568, andEnterobacter cloacae. We show that the overexpression ofrarAresults in a multidrug resistance phenotype which requires a functional AcrAB efflux pump but is independent of the other AraC regulators. Quantitative real-time PCR experiments show thatrarA(MGH 78578 KPN_02968) and its neighboring efflux pump operonoqxAB(KPN_02969_02970) are consistently upregulated in clinical isolates collected from various geographical locations (Chile, Turkey, and Germany). Our results suggest thatrarAoverexpression upregulates theoqxABefflux pump. Additionally, it appears thatoqxR, encoding a GntR-type regulator adjacent to theoqxABoperon, is able to downregulate the expression of theoqxABefflux pump, where OqxR complementation resulted in reductions to olaquindox MICs.

Preparing Process and Properties of Collagen Modified Cotton Fiber

2011 ◽  
Vol 236-238 ◽  
pp. 1415-1419 ◽  
Author(s):  
Yun Hui Xu ◽  
Zhao Fang Du
Keyword(s):  
Cotton Fiber ◽  
Treatment Time ◽  
Ph Value ◽  
Periodate Oxidation ◽  
Aqueous Acetic Acid ◽  
Collagen Concentration ◽  
Acid Media ◽  
Xps Characterization ◽  
Aldehyde Groups

In order to develop cotton fabric underwear with the health care function, the cotton fiber was modified with the collagen (CMCF) using periodate oxidation method. The aldehyde groups on the glucose chains of the oxidized cotton cellulose were reacted with the amino groups of collagen to obtain the CMCF, and the oxidized cellulose was crosslinked with collagen in aqueous acetic acid media. The effects of collagen concentration, treatment time, reaction temperature, pH value of solution and periodate concentration on the amount of collagen crosslinked on cotton fiber were respectively discussed, and the optimal reaction technology was obtained. XPS characterization of the modified cotton fiber showed a characteristic peak about 400.0–405.0 eV corresponding to collagen, which indicated that the collagen was combined on the surface of cotton fiber. The mechanical properties of the collagen modified cotton fiber were improved. The resulting CMCF is a new natural ecological fiber and has the extensive application as a carrier for the controlled release of drugs.

scholarly journals Understanding employee turnover in humanitarian organizations

2016 ◽  
Vol 48 (4) ◽  
pp. 208-214 ◽  
Author(s):  
Rameshwar Dubey ◽  
Angappa Gunasekaran ◽  
Nezih Altay ◽  
Stephen J Childe ◽  
Thanos Papadopoulos
Keyword(s):  
Employee Turnover ◽  
Factor Loading ◽  
Personal Factors ◽  
Related Factors ◽  
Content Type ◽  
Factors Affecting ◽  
Work Related ◽  
Humanitarian Organizations ◽  
Using Data ◽  
High Level

Purpose – At a time when the number and seriousness of disasters seems to be increasing, humanitarian organizations find that besides their challenging work they are faced with problems caused by a high level of turnover of staff. The paper aims to discuss these issues. Design/methodology/approach – Based on the 24 variables leading to employee turnover identified by Cotton and Tuttle (1986) the authors analyse the work-related, external and personal factors affecting employee turnover in humanitarian organizations, using a survey of members of the Indian National Institute of Disaster Management. Findings – Results indicated that the three factors are present. Of the external factors, only employment perception had a factor loading over 0.7; of the work-related factors, all were significant; of the personal factors, biographical information, marital status, number of dependants, aptitude and ability and intelligence had the highest loadings. It was also shown that behavioural intentions and net expectation were not significant. Originality/value – Only a few studies reported on employee turnover and its reasons are not well understood in the context of humanitarian organizations. To address this need, the aim of this paper is to explore the personal reasons impacting employee turnover in humanitarian organizations. In the study the authors have adopted 24 variables used in Cotton and Tuttle (1986) and classified into constructs to explain turnover, and further tested the model using data gathered from humanitarian organizations.

scholarly journals Understanding consumer loyalty to technology-based self-services with credence qualities

2015 ◽  
Vol 29 (6/7) ◽  
pp. 522-532 ◽  
Author(s):  
Lisa Schuster ◽  
Judy Proudfoot ◽  
Judy Drennan
Keyword(s):  
Professional Services ◽  
Content Type ◽  
Consumer Responses ◽  
Factors Affecting ◽  
Behavioral Loyalty ◽  
Behavioral Domain ◽  
Continued Use ◽  
Self Service ◽  
The Impact ◽  
Goal Directed Behavior

Purpose – This paper aims to use the Model of Goal-Directed Behavior (MGB) to examine the factors affecting consumers’ continued use of emerging technology-based self-services (TBSSs) with credence qualities. Professional services, which traditionally require specialized knowledge and high levels of interpersonal interaction to produce owing to their credence qualities, are increasingly delivered via self-service technologies. Health services delivered via mobile devices, for example, facilitate self-care without direct involvement from health professionals. Design/methodology/approach – A mental health service delivered via the Internet and mobile phone, myCompass, was selected as the research context. Twenty interviews were conducted with users of myCompass and the data were thematically analyzed. Findings – The findings of the study showcase the unique determinants of consumers’ continued use of TBSSs with credence qualities relative to the more routine services which have been the focus of extant research. The findings further provide support for the utility of the MGB in explaining service continuance, although the importance of distinguishing between extrinsic and intrinsic motivational components of behavioral desire and capturing the impact of social influence beyond subjective norms is also highlighted. Originality/value – This study contributes to recent research examining differences in consumer responses across TBSSs and behavioral loyalty to these services. It also provides empirical evidence for broadening and deepening the MGB within this behavioral domain.

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