Dissertation > Excellent graduate degree dissertation topics show

Determination of Chromium(VI) by Automatic Reference Reverse Flow Colorimetry and the Application in Leather Analysis

Author: LiuWeiGuo
Tutor: ZhangXinShen
School: Sichuan University
Course: Leather Chemistry and Engineering
Keywords: chromium(Ⅵ) Flow injection analysis leather determination Extract
CLC: TS513
Type: Master's thesis
Year: 2002
Downloads: 71
Quote: 1
Read: Download Dissertation

Abstract


For its excellent properties, the chemicals contain chromium have been widely used in many fields. In nature, chromium commonly exists in two oxidation states: chromium(III) and chromium(VI). Chromium(III) has long been recognized as an essential element for life. However, chromium(VI) is highly carcinogenic and has sever damage to human and other lives. There are numerous regulations on permissible limits of chromium(VI) in water and wastewater and industry products. Spectrophotometry, atomic absorption spectrometry and other analytical methods are applied in determination of chromium(VI).In this paper, a new method, Automatic Reference reverse Flow Colorimetry was introduced. And the application in leather analysis was also advanced.Firstly, three flow injection systems were compared and the Automatic Reference reverse Flow injection system was recognized the most fit for analysis of chromium(VI). Through tests, the conditions for analysis of chromium(VI) was chose : 0.5 mmol/L 1,5-diphenylcarbazide dissolved in 0.4 mol/L H2SO4, the flow rate of reaction solution was 2.5 ml/min, the length of reactor was 3m, and the volume of sample injection valve was 235.5ul. The method was also evaluated under this condition. The calibration graph was linear in the range of 1 x10-6-1580x 10-6g/L and the detection limit was 0.46x10-6g/L .The conditions of applying the Automatic Reference reverse Flow>Colorimetry in leather analysis was also discussed. Leather sample was extracted in 0.1 mol/L Na2HPO4 solution (pH8.0) for 3h with temperature of 25C , to avoid the oxidation of chromium(III), protection with nitrogen was suggested. The extracted samples was then bleached by flowing through DJ-4 resin.With its high sensitive, resistance to interference, easy to operate and other excellence, the Automatic Reference reverse Flow Colorimetry could be used for determination of chromium(VI) in water, wastewater, leather and other samples.

Related Dissertations

  1. Effect on Quality of Chilled Meat by Irradiation and Hawthorn Flavonoids Extract,TS251.51
  2. Studies on Preparation, Purification of the Sika Deer Placenta Oligopeptide,R284.1
  3. Actinidia arguta flavonoids Purification and structural identification,R284
  4. Studies on the Component Type and Hypocholesterolaemia Effect of the Effective Constituent Groups in the Fistular Onion Stalk,R285
  5. Grape skin extract inhibition mechanism of breast cancer metastasis,R737.9
  6. The Study on Anti-obesity Function and Chemical Compositions of a Formula Composed of Aromatic Plants,R284
  7. Blackberry mobile phone operating system based on Security Mechanism,TP309.7
  8. Citrus aurantium extract and flavonoids in new exploration adsorption separation,TQ461
  9. Plant extracts against Tetranychus cinnabarinus screening and biological activity of the active ingredient,S482.52
  10. Antlers disc anti-inflammatory effects of extracts,R285.5
  11. Research on Extraction and Separation and Quality Standards of Water-soluble Phenolic Constituents in Salvia,R284
  12. Study on Extract Prepared of Kudzu Vine and Its Effect on Resistance Osteoporosis,R285.5
  13. Study on the Functions of Water Extract from Vaccinium Bracteatum Thumb. Leaves,R285
  14. Preliminary Study on the Utilization of Fruit of Schisandra Chinensis,R284
  15. Ku-shui Rose Essential Oil and Rose Residue Pigment Extraction and Purification,TS264.4
  16. A Study on Chemical Composition and Solid Extracts Properties of Rwandan CTC Teas,TS272
  17. Preparation and Properties of Dietary Fibre from Barley Spent Grains and Its Application in Steam Bread,TS213.2
  18. Study on the Extraction of the Ovine Pancreatin Process and the Kinetics of Digestion of Casein,TQ465
  19. Study on Extraction, Purification and the Microcapsule of Xingjiang Qiamagu,TQ461
  20. Technology of Flavonoids Extraction in Lingwu Long Date and Evaluation of Its Antioxidizing Activity,S665.1
  21. Rabbit skin inflamed by vaccinia virus extract injection on fracture healing and its molecular mechanism of experimental study,R965

CLC: > Industrial Technology > Light industry,handicrafts > Leather Industry > Leather school > Leather chemical
© 2012 www.DissertationTopic.Net  Mobile