Aqueous Two-phase System For Dyes Extraction From Aqueous Discharges By Liquid Chromatography-triple Stage Quadrupole Mass Spectrometry

Due to rapid industrialization,a lot of chemicalsincluding dyes are manufactured and used in day-todaylife.Dyes are extensively used in textile,dyeing,paper printing,color photography,food,cosmetic,and other industries.Approximately,10,000 differentdyes and pigments are used industrially andover 0.7 million tonnes of dyes are producedannually,worldwide.Effluents from the textileindustry usually contain highconcentrations oforganic compounds and are characterized by strongcolor as well as high chemical oxygen demand andtotal organic carbon values.During the dyeing process,10%–15%of the dye is lost in the effluent andcolor is the first contaminant to be recognized inwastewater and the presence of very small amountsof dyes in water is highly visible and undesirable.Discharge of wastewaters containing dyes into surfacewater bodies stops the reoxygenation capacity of thereceiving water and cuts off sunlight,thereby upsetsbiological activity in aquatic life.Moreover,somedyes can be toxic and/or carcinogenic to mammaliananimals.As a result,the development of cost-effective detection and preliminary treatment method is a top priority.This article choosethe aqueous two-phase systems（ATPSs）which is an environmentally safe and economicallyviable method to extract textile dye from wastewater.There are a few studies publishedon a successful usage of the ATPSs for separation andextraction of the different dyes.Separations conducted in ATPSs offer a greatnumber of advantages over the conventional separationtechniques.Among them the most relevant arerapid mass transfer due to low interfacial tension,rapid and selective separation,easiness of operationmode,and reliability in scale-up.An ATPS isformed by incompatibility of small molecularsolvents and ainorganicsalt in aqueous solutions.Spontaneousseparation of the phases occurs beyond a criticalconcentration of these components,resulting in twophases,enriched with respect to one of the components.ATPS has been most commonly used for the separation of biomolecule（e.g.,Proteins）,monoclonal antibodies（mAbs）,low molecular weight compounds（e.g.,phytochemicals and secondary metabolites）,dru residues in food and water,even involved in environment remediation.An aqueous two-phase extraction system（ATPS）was developed for the analysis of dyes in textile effluents by liquid chromatography-triple stage quadrupole mass spectrometry（HPLC-MS/MS）.The aim of this work includes the following points:1.Introduced the basic situation applications and toxicologyof dyes,and several common sample pretreatment technologies.Emphatically expounded the overview application of ATPS,the influence factors of aqueous two-phase extraction system.2.An acetonitrile–salt aqueous two-phase extraction system（ATPS）was developed and applied in theextraction of 7 disperse dyes in textile effluents.HPLC-MS/MS were applied in the determination of theanalytes.The mixture was ultrasonically shaken for 1min.The ATPS wasformed.The dyes in ATPS was gathered together and suspended in the acetonitrile phase.The parameters affecting the extraction efficiency,such a volume ofextraction solvent,type and amount of salt,pH value of sample solution,ultrasoundextraction time were investigated.The limits of detection of7 disperse dyes ranged from0.003 to 0.052μgL^-1.When the present method was applied in the analysis of water samples,the recoveries of the analytesranged from 96 to 107%and the relative standard deviations were lower than 6.6%.3.A simple extraction method based on alcohols-salts aqueous two-phase system was developed forseparation and enrichment of 11 dyes in textile effluents.A detailed study on the extraction efficiencies of 7disperse dyes（disperse yellow 3,disperse blue 35,disperse red 1,disperse orange 1,disperse blue 106,disperse orange 37 and disperse brown 1）and 4acid dyes（acid red 1,acid red 87,acid orange 7 and acid blue 83）using ATPS composed of alcohols（ethanol,t-butanol,1-propanol and 2-propanol）and an inorganic salt（K₂HPO₄,（NH₄）₂SO₄,K₂CO₃）is here addressed.Some experimentalparameters,such as typeof extraction solvent,pH value ofsample solution,salt concentration and extraction time were investigated and optimized.The enrichment ranged from 38 to 49 and the detection limits were in the range of 0.0033 to 0.037μg L^-1for11 dyes.4.Summed up the thesis and summarized the main conclusions of experiments.Comparative analysis of the small molecule organic solvent-alcohol/saltand acetonitrile/salt system of the aqueous two-phase system for dyes separation and extraction.The ATPS is able to give high recovery yield and is easily to scale up.It is also very economic andenvironment friendly method.