Poster Presentation
1
USING JOB’S METHOD TO DETERMINE THE STOICHIOMETRIC RATIO OF A METAL-AMINOPOLYCARBOXYLATE COMPLEX IN A NON-AQUEOUS MEDIUM Nsombi J. Roberts Department of Chemistry, Southern University and A&M College Baton Rouge, LA INTRODUCTION First world countries are plagued with high density industrialized areas that produce large amounts of pollutants on a daily basis. This is not to be confused with the general term for unwanted remains and byproducts or waste that these corporations expel. A pollutant is described as a waste material that pollutes or contaminates the environment. Pollution is categorized into several different groups: air, thermal, soil, radioactive, and water. Water pollution occurs when pollutants spread from a source to the environment, leaving natural resources such as water systems fouled by human existence. Contaminated water sources can contain various dense, potentially toxic metals or heavy metals that are a danger to the human condition. The heavy metals of major health concern are cadmium, mercury, lead and arsenic. Other heavy metals that are less toxic are manganese, chromium, cobalt, nickel, copper, zinc, selenium, silver, antimony and thallium. These heavy metals can only be removed through transformation from one oxidation state or organic complex to another. As of 2016, the major environmental issue at hand in the United States is the drinking water contamination crisis in Flint, Michigan. The city of Flint is currently in a federal state of emergency which allows the federal government to take the forefront on handling the issue at hand. The drinking water for the city of Flint was switched from the same source used by the city of Detroit to the Flint River, a previous back up source. The city originally did not use the Flint River as a primary source because the overall cost for the treatment of that water was more expensive than water from Lake Huron, Detroit’s current water source.. The water from the Flint River was contaminated by lead that leached into the water system from outdated pipes. Leaching is described as the process of removing a soluble mineral or chemical from a solid source with a liquid either naturally or through forced means. The improper treatment of the water and the ineffective methods used to remove the leached lead posed a serious health risk to the citizens of Flint. Lead is the second most hazardous metal according to the Priority List of the US Environmental Protection Agency. News stations across the country displayed the unnatural discoloration of water in the homes of dozens of Flint residents. Many children were found having highly elevated levels of lead in their blood stream which translates to lead poisoning. Lead poisoning can lead to “deficits in intellectual functioning, academic performance, problem solving skills, motor skills, memory and executive functioning are consistently observed in lead-exposed children, in addition to an increased likelihood of experiencing ADHD and having conduct problems in childhood, and decreased brain volume in adulthood.” Green chemistry is “the utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and applications of chemical products.” It is upon this foundation that purification systems were born. Water purification methods are costly to the average citizen forced by their social economic status to live in these nearly uninhabitable areas. The current green chemistry methods in place, while less costly and efficient, employ an aminopolycarboxylic acid that is a suspected carcinogenic to humans.. The increasing world population has led to a rapid increase in pollution. The increasing cost of pollutant removal has led the world to turn to producing newer methods. There is a need for a sequestering agent that has effectiveness in removing heavy metals from solutions, has minimum health effect, and is cost efficient. Pollutants in water systems and soils negatively affect the lifecycles of plants and animals, ultimately affecting human life. Metal removal from aqueous and non-aqueous solutions through the use of an aminopolycarboxylic acid can be a cheaper and more efficient purification process. The purpose of this study is to develop a green chemistry method for removing pollutants from aqueous or non-aqueous solvents. ABSTRACT The increasing world population has led to a rapid increase in pollution. The increasing cost of pollutant removal has led the world to turn to producing newer, cheaper, and safer methods. There is a need for a sequestering agent that has effectiveness in removing heavy metals from solutions, has minimum health effect, and is cost efficient. This study sets to utilize an aminopolycarboxylic acid to develop a method that is effective in removing pollutants from aqueous and non-aqueous mediums. The titrimetric methods of analysis were used to develop a method that is cheap and safe for removing pollutants such as toxic metals from non-aqueous and aqueous mediums. The physiochemical properties of the aminopolycarboxylic acid observed were used to develop a method that is cheap and safe for removing pollutants such as toxic metals from non-aqueous solutions. 3, 3’, 3”-Nitrilotripropionic acid (NTP) was synthesized from acrylic acid and β-Alanine using Michael Addition and coordinated to a metal complex in a non-aqueous solution. The method of continuous variation was used to find the stoichiometric ratio of the metal complex. Specific Aim 1: Synthesis of 3, 3’, 3” – Nitrilotriproionic acid from β-Alanine and acrylic acid. Specific Aim 2: Coordination of synthesized 3, 3’, 3” – Nitrilotriproionic acid to Cupric chloride in a non- aqueous medium using the Job’s Method Results Conclusion From the solubility test and melting point test, it can be concluded that NTP was successfully made. The process of forming NTP from b -alanine and acrylic acid was faster than previous methods and produced a substantial yield. The conclusion that the time-consuming process is due to the third step of reaction has been disproven. Due to the first leg of NTP already being attached, it can be concluded that the formation of the primary amine compound, the first step, is the rate limiting step. It has also been concluded that NTP fully deprotonates in basic mediums, making it the optimal environment for coordination to metal ion. This confirms the pH dependency of NTP coordination. Future studies of NTP coordination should be conducted in basic mediums or with a salt form of NTP to allow maximum potential for coordination. The NTP ligand successfully coordinated to Copper, as observed by the distinct color changes with varying metal to ligand ratios. A single new peak emerged at 726.7 nm at a metal to ligand ratio of 1:9, giving a starting point for future studies for finding the to the stoichiometric ratio. Other methods such as the mole-ratio and slope-ratio methods should be examined to find an exact ratio. Acknowledgments Dr. Scott A. Wicker Southern University Chemistry Department Zeta Phi Beta Sorority, Inc. Dolores Margaret Richard Spikes Honors College References • Järup, L., Hazards of heavy metal contamination. BritishMedical Bulletin 2003, 68 (1), 167-182. • Carlos Garbisu, I. A., Phytoextraction: a cost-effective plant-based technology for the removal of metals from the environment. Bioresource Technology 2001, 77 (3), 229- 236. • Cavanaugh,P. Analysis of the Flint River as a Permanent Water Supply for the City of Flint - July 2011; September 9, 2011, 2011; pp 1-15. • Eriberto Vagner de Souza Freitas, C. W. A. d. N., The use of NTA for lead phytoextractionfrom soil from a battery recycling site. Journal of Hazardous Materials 2009, 171 (1-3), 833-837. • Kathryn M. Barker, F. Q. Lead poisoning: Sources of exposure, health effects and policy implications. http://journalistsresource.org/studies/society/public-health/lead- poisoning-exposure-health-policy) (accessed 12 February 2016). • Warner, P. A. J., Green Chemistry: Theory and Practice. Oxford University Press: New York, 2000; p 152. • Opinion on trisodium nitrilotriacetate (NTA). http://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_046 .pdf (accessed 10 February 16). • Barakat, M. A., New trends in removing heavy metals from industrial wastewater. Arabian Journal of Chemistry 2011, 4 (4), 361-377. • Wicker, S. A. Development of a Green Soft Chemical Method for the Synthesis of Cathode Materials Utilized in Lithium-ion Energy Storage Technologies. Dissertation, Southern University and A & M College, Baton Rouge, Louisiana, 2011. • Sims, T. E. THE SYNTHESIS, STRUCTURAL, AND PHYSICOCHEMICAL CHARACTERIZATION OF 3,3’,3’’ NITRILOTRIPROPIONIC ACID. Southern University and A&M College, Baton Rouge, Louisiana, 2015. • Govender,K. K. Theoretical studies ofnitrilotriaceticacid and nitrilotripropionicacid geometries for estimation of the stability of metal complexes by Density Functional Theory. Dissertation, University of Pretoria, Pretoria, 2009. • Bruce Averill, P. E., Chemistry: Principles, Patterns, and Applications 1st ed.; Pearson: San Francisco, 2007; p 1250. • Carroll, C. Determiningthe StoichiometricRatio of Iron(III) Chloride and synthesized NitrilotripropionicAcid usingthe Job’s Method. Southern University and A&M College, Baton Rouge, Louisiana, 2015. • Douglas A. Skoog, F. J. H., Stanley R. Crouch, Principles of Instrumental Analysis. 6 ed.; Thomson Brooks/Cole: Belmont, 2006; p 1056. • I. M. KOLTHOFF, T. B. R., Acid-Base Strength in Dimethyl Sulfoxide. Inorganic Chemistry 1962, 1 (2), 189-194. • Devon W. Meek, R. S. D., T. S. Piper, Spectrochemical Studies of Dimethyl Sulfoxide, Tetramethylene Sulfoxide, and Pyridine N-Oxide as Ligands with Nickel(II), Chromium(III), and Cobalt(II). Inorganic Chemistry 1962, 1 (2), 285-289. Michael Addition Synthesis of NTP Titration of NTP in NaOH Volume NTP (L) moles of NTP Volume Copper (II) Chloride (L) moles of Copper (II) ion Total Moles Mole Fraction of Ligand Mole Fraction of Metal Mole Ratio of Ligand to Metal 0 0.0000E+00 0.005 1.0265E-05 1.0265E-05 0 1 0/1 0.0005 1.0265E-06 0.0045 9.2385E-06 1.0265E-05 0.1 0.9 1/9 0.001 2.0530E-06 0.004 8.2120E-06 1.0265E-05 0.2 0.8 1/4 0.0015 3.0795E-06 0.0035 7.1855E-06 1.0265E-05 0.3 0.7 3/7 0.002 4.1060E-06 0.003 6.1590E-06 1.0265E-05 0.4 0.6 2/3 0.0025 5.1325E-06 0.0025 5.1325E-06 1.0265E-05 0.5 0.5 1/1 0.003 6.1590E-06 0.002 4.1060E-06 1.0265E-05 0.6 0.4 3/2 0.0035 7.1855E-06 0.0015 3.0795E-06 1.0265E-05 0.7 0.3 7/3 0.004 8.2120E-06 0.001 2.0530E-06 1.0265E-05 0.8 0.2 4/1 0.0045 9.2385E-06 0.0005 1.0265E-06 1.0265E-05 0.9 0.1 9/1 0.005 1.0265E-05 0 0.0000E+00 1.0265E-05 1 0 1/0 Molarity of NTP (M) Molarity of Copper (II) Chloride (M) Total Volume (mL) 0.002053 0.002053 5 Phase Diagram for NTP with Copper (II) Chloride in DMSO Varying ratios (M:L) of 2mM Copper (II) chloride and 2mM NTP in DMSO. From left to right: 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:1. Varying ratios (M:L) of 0.05M Copper (II) chloride and 0.05M NTP in DMSO. From left to right: 1:0, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, 0:1. 0 0.1 0.2 0.3 0.4 0.5 0.6 380 480 580 680 780 880 Absorbance Wavelength (nm) Continuous Variation of 0.002M CuCl_2 and 0.002M NTP in DMSO 1:0 9:1 8:2 7:3 6:4 5:5 4:6 3:7 2:8 1:9 0:1 Metal to Ligand Ratio Peak= 391.6 nm Copper (II) chloride in water and Copper (II) chloride in DMSO Enhanced spectrum of 2mM NTP and 2mM Copper (II) Chloride in DMSO at (from top left to right to bottom left to right) metal to ligand ratios of 4:6, 3:7, 2:8, and 1:9 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 380 480 580 680 780 880 Absorbance Wavelength (nm) Absorbance of 1:9 0.05M CuCl_2 and 0.05M NTP in DMSO Peak= 726.7 nm
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USINGJOB’SMETHODTODETERMINETHESTOICHIOMETRICRATIOOFAMETAL-AMINOPOLYCARBOXYLATECOMPLEXINANON-AQUEOUSMEDIUM
NsombiJ.RobertsDepartmentofChemistry,SouthernUniversityandA&MCollege
BatonRouge,LA
INTRODUCTIONFirst world countries are plagued with high density industrialized areas that produce largeamounts of pollutants on a daily basis. This is not to be confused with the general term forunwanted remains and byproducts or waste that these corporations expel. A pollutant isdescribed as a waste material that pollutes or contaminates the environment. Pollution iscategorized into several different groups: air, thermal, soil, radioactive, and water. Waterpollution occurs when pollutants spread from a source to the environment, leaving naturalresources such as water systems fouled by human existence. Contaminated water sourcescan contain various dense, potentially toxic metals or heavy metals that are a danger to thehuman condition. The heavy metals of major health concern are cadmium, mercury, leadand arsenic. Other heavy metals that are less toxic are manganese, chromium, cobalt,nickel, copper, zinc, selenium, silver, antimony and thallium. These heavy metals can onlybe removed through transformation from one oxidation state or organic complex toanother. As of 2016, the major environmental issue at hand in the United States is thedrinking water contamination crisis in Flint, Michigan. The city of Flint is currently in afederal state of emergency which allows the federal government to take the forefront onhandling the issue at hand. The drinking water for the city of Flint was switched from thesame source used by the city of Detroit to the Flint River, a previous back up source. Thecity originally did not use the Flint River as a primary source because the overall cost for thetreatment of that water was more expensive than water from Lake Huron, Detroit’s currentwater source.. The water from the Flint River was contaminated by lead that leached intothe water system from outdated pipes. Leaching is described as the process of removing asoluble mineral or chemical from a solid source with a liquid either naturally or throughforced means. The improper treatment of the water and the ineffective methods used toremove the leached lead posed a serious health risk to the citizens of Flint. Lead is thesecond most hazardous metal according to the Priority List of the US EnvironmentalProtection Agency. News stations across the country displayed the unnatural discolorationof water in the homes of dozens of Flint residents. Many children were found having highlyelevated levels of lead in their blood stream which translates to lead poisoning. Leadpoisoning can lead to “deficits in intellectual functioning, academic performance, problemsolving skills, motor skills, memory and executive functioning are consistently observed inlead-exposed children, in addition to an increased likelihood of experiencing ADHD andhaving conduct problems in childhood, and decreased brain volume in adulthood.” Greenchemistry is “the utilization of a set of principles that reduces or eliminates the use orgeneration of hazardous substances in the design, manufacture, and applications ofchemical products.” It is upon this foundation that purification systems were born. Waterpurification methods are costly to the average citizen forced by their social economic statusto live in these nearly uninhabitable areas. The current green chemistry methods in place,while less costly and efficient, employ an aminopolycarboxylic acid that is a suspectedcarcinogenic to humans.. The increasing world population has led to a rapid increase inpollution. The increasing cost of pollutant removal has led the world to turn to producingnewer methods. There is a need for a sequestering agent that has effectiveness in removingheavy metals from solutions, has minimum health effect, and is cost efficient. Pollutants inwater systems and soils negatively affect the lifecycles of plants and animals, ultimatelyaffecting human life. Metal removal from aqueous and non-aqueous solutions through theuse of an aminopolycarboxylic acid can be a cheaper and more efficient purificationprocess. The purpose of this study is to develop a green chemistry method for removingpollutants fromaqueous or non-aqueous solvents.
ABSTRACTThe increasing world population has led to a rapid increase inpollution. The increasing cost of pollutant removal has led theworld to turn to producing newer, cheaper, and safer methods.There is a need for a sequestering agent that has effectiveness inremoving heavy metals from solutions, has minimum healtheffect, and is cost efficient. This study sets to utilize anaminopolycarboxylic acid to develop a method that is effective inremoving pollutants from aqueous and non-aqueous mediums.The titrimetric methods of analysis were used to develop amethod that is cheap and safe for removing pollutants such astoxic metals from non-aqueous and aqueous mediums. Thephysiochemical properties of the aminopolycarboxylic acidobserved were used to develop a method that is cheap and safefor removing pollutants such as toxic metals from non-aqueoussolutions. 3, 3’, 3”-Nitrilotripropionic acid (NTP) was synthesizedfrom acrylic acid and β-Alanine using Michael Addition andcoordinated to a metal complex in a non-aqueous solution. Themethod of continuous variation was used to find thestoichiometric ratio of the metal complex.
SpecificAim1:Synthesisof3,3’,3”–Nitrilotriproionic acidfromβ-Alanineandacrylicacid.
SpecificAim2:Coordinationofsynthesized3,3’,3”–Nitrilotriproionic acidtoCupricchlorideinanon-aqueousmediumusingtheJob’sMethod
Results ConclusionFrom the solubility test and melting point test, it can be concluded that NTP wassuccessfully made. The process of forming NTP from b-alanine and acrylic acid wasfaster than previous methods and produced a substantial yield. The conclusion that thetime-consuming process is due to the third step of reaction has been disproven. Due tothe first leg of NTP already being attached, it can be concluded that the formation ofthe primary amine compound, the first step, is the rate limiting step. It has also beenconcluded that NTP fully deprotonates in basic mediums, making it the optimalenvironment for coordination to metal ion. This confirms the pH dependency of NTPcoordination. Future studies of NTP coordination should be conducted in basicmediums or with a salt form of NTP to allow maximum potential for coordination. TheNTP ligand successfully coordinated to Copper, as observed by the distinct colorchanges with varying metal to ligand ratios. A single new peak emerged at 726.7 nm ata metal to ligand ratio of 1:9, giving a starting point for future studies for finding the tothe stoichiometric ratio. Other methods such as the mole-ratio and slope-ratio methodsshould be examined to find an exact ratio.
AcknowledgmentsDr. Scott A. WickerSouthern University Chemistry DepartmentZeta Phi Beta Sorority, Inc.Dolores Margaret Richard Spikes Honors College
References• Järup,L.,Hazardsofheavymetalcontamination.BritishMedicalBulletin2003, 68 (1),
167-182.• CarlosGarbisu,I.A.,Phytoextraction:acost-effectiveplant-basedtechnologyforthe
removalofmetalsfromtheenvironment.Bioresource Technology2001, 77 (3),229-236.
• Cavanaugh,P.AnalysisoftheFlintRiverasaPermanentWaterSupplyfortheCityofFlint- July2011;September9,2011,2011;pp1-15.
• Eriberto Vagner deSouzaFreitas,C.W.A.d.N.,TheuseofNTAforleadphytoextraction fromsoilfromabatteryrecyclingsite.JournalofHazardousMaterials2009, 171 (1-3),833-837.
• KathrynM.Barker,F.Q.Leadpoisoning:Sourcesofexposure,healtheffectsandpolicyimplications.http://journalistsresource.org/studies/society/public-health/lead-poisoning-exposure-health-policy)(accessed12February2016).
• Warner,P.A.J.,GreenChemistry:TheoryandPractice.OxfordUniversityPress:NewYork,2000;p152.
• Opinionontrisodiumnitrilotriacetate (NTA).http://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_046.pdf (accessed10February16).
• Barakat,M.A.,Newtrendsinremovingheavymetalsfromindustrialwastewater.ArabianJournalofChemistry2011, 4 (4),361-377.
• Wicker,S.A.DevelopmentofaGreenSoftChemicalMethodfortheSynthesisofCathodeMaterialsUtilizedinLithium-ionEnergyStorageTechnologies.Dissertation,SouthernUniversityandA&MCollege,BatonRouge,Louisiana,2011.
• Sims,T.E.THESYNTHESIS,STRUCTURAL,ANDPHYSICOCHEMICALCHARACTERIZATIONOF3,3’,3’’NITRILOTRIPROPIONICACID.SouthernUniversityandA&MCollege,BatonRouge,Louisiana,2015.
• Govender,K.K.Theoreticalstudiesofnitrilotriacetic acidandnitrilotripropionicacidgeometriesforestimationofthestabilityofmetalcomplexesbyDensityFunctionalTheory.Dissertation,UniversityofPretoria,Pretoria,2009.
• BruceAverill,P.E.,Chemistry:Principles,Patterns,andApplications1sted.;Pearson:SanFrancisco,2007;p1250.
• Carroll,C.DeterminingtheStoichiometricRatioofIron(III)ChlorideandsynthesizedNitrilotripropionicAcidusingtheJob’sMethod.SouthernUniversityandA&MCollege,BatonRouge,Louisiana,2015.
• DouglasA.Skoog,F.J.H.,StanleyR.Crouch,PrinciplesofInstrumentalAnalysis.6ed.;ThomsonBrooks/Cole:Belmont,2006;p1056.
• I.M.KOLTHOFF,T.B.R.,Acid-BaseStrengthinDimethylSulfoxide.InorganicChemistry1962, 1 (2),189-194.
• DevonW.Meek,R.S.D.,T.S.Piper,SpectrochemicalStudiesofDimethylSulfoxide,Tetramethylene Sulfoxide,andPyridineN-OxideasLigandswithNickel(II),Chromium(III),andCobalt(II).InorganicChemistry1962, 1 (2),285-289.
MichaelAdditionSynthesisofNTP
TitrationofNTPinNaOH
VolumeNTP(L)
molesofNTP
VolumeCopper(II)Chloride(L)
molesofCopper(II)ion
TotalMolesMoleFraction
ofLigand
MoleFractionof
Metal
MoleRatioofLigandtoMetal
0 0.0000E+00 0.005 1.0265E-05 1.0265E-05 0 1 0/10.0005 1.0265E-06 0.0045 9.2385E-06 1.0265E-05 0.1 0.9 1/90.001 2.0530E-06 0.004 8.2120E-06 1.0265E-05 0.2 0.8 1/40.0015 3.0795E-06 0.0035 7.1855E-06 1.0265E-05 0.3 0.7 3/70.002 4.1060E-06 0.003 6.1590E-06 1.0265E-05 0.4 0.6 2/30.0025 5.1325E-06 0.0025 5.1325E-06 1.0265E-05 0.5 0.5 1/10.003 6.1590E-06 0.002 4.1060E-06 1.0265E-05 0.6 0.4 3/20.0035 7.1855E-06 0.0015 3.0795E-06 1.0265E-05 0.7 0.3 7/30.004 8.2120E-06 0.001 2.0530E-06 1.0265E-05 0.8 0.2 4/10.0045 9.2385E-06 0.0005 1.0265E-06 1.0265E-05 0.9 0.1 9/10.005 1.0265E-05 0 0.0000E+00 1.0265E-05 1 0 1/0
MolarityofNTP(M)
MolarityofCopper(II)Chloride(M)
TotalVolume(mL)
0.002053 0.002053 5
PhaseDiagramforNTPwithCopper(II)ChlorideinDMSO
Varyingratios(M:L)of2mMCopper(II)chlorideand2mMNTPinDMSO.Fromlefttoright:1:0,9:1,8:2,7:3,6:4,5:5,4:6,3:7,2:8,1:9,0:1.
Varyingratios(M:L)of0.05MCopper(II)chlorideand0.05MNTPinDMSO.Fromlefttoright:1:0,9:1,8:2,7:3,6:4,5:5,4:6,3:7,2:8,1:9,0:1.
0
0.1
0.2
0.3
0.4
0.5
0.6
380 480 580 680 780 880
Absorban
ce
Wavelength(nm)
ContinuousVariationof0.002MCuCl_2and0.002MNTPinDMSO
1:0
9:1
8:2
7:3
6:4
5:5
4:6
3:7
2:8
1:9
0:1
Metal toLigandRatio
Peak=391.6nm
Copper(II)chlorideinwaterandCopper(II)chlorideinDMSO
Enhancedspectrumof2mMNTPand2mMCopper(II)ChlorideinDMSOat(fromtoplefttorighttobottomlefttoright)metaltoligandratiosof4:6,3:7,2:8,and1:9
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
380 480 580 680 780 880
Absorba
nce
Wavelength(nm)
Absorbanceof1:90.05MCuCl_2and0.05MNTPinDMSO
Peak=726.7nm
