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Title of Thesis

Muhammad Abdul Quddus
Institute/University/Department Details
Department of Applied Chemistry/ University of Karachi
Number of Pages
Keywords (Extracted from title, table of contents and abstract of thesis)
catalytic oxidation, asphalt, asphaltene, petroleum asphalt, blown asphalt

The effect of air blowing on paving grade vacuum residue to produce high softening point industrial grade asphalt have been studied in a gas-liquid reactor.

Factors such as reactor design, temperature, air flow rate and time were investigated. Response of different feedstock sot metallic chloride catalysts were examined.

The course of reaction was followed by measuring penetration and softening point of the blown product at regular intervals. It was found that the catalytic activity of metallic chloride could be enhanced by combining the chloride with manganese dioxide. Quantity of chloride catalyst, the amount of blown distillate and acidic gases are considerably reduced, by the addition of manganese dioxide for a given degree of hardness of the blown product.

Chemical changes occurring during asphalt air blowing has been evaluated by adsorption-adsorption chromatography. The amount of asphaltene increases at the expense of saturate, namphthene aromatic and polar aromatic. Identical fractional chemical composition of different asphalts results in identical penetration and softening point. However, high molecular weight hydrocarbons may also be connected with hardening of asphalt.

N.m.r. studies show transformation of straight chain hydrocarbons to cyloparaffins which in turn, are dehydrogenated to form aromatic hydrocarbons during air blowing. Dehydrogenation of asphalt molecules is supported by elemental analysed. U.v spectra show the formation of polycondensed aromatic, while f.t.i.r. spectra indicate incorporation of oxygen and cross linking in blown asphalt.

Structural characterization of asphalt by instrumental methods, suggest that the blown product becomes more complex and condensed leading to increase in molecular weight. These changes are accelerated by active catalysts. The air blowing induces a movement of components from non-polar to more polar fractions. A general transformation mechanism has been proposed.

Quantity and characteristics of the effluents have been found to be dependent on the chemical nature and physical properties of feed as well as on the catalyst used.

Download Full Thesis
1559.86 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents
66.53 KB
2 1 Introduction 1
33.91 KB
  1.1 Objectives 2
  1.2 Layout Of The Thesis 3
3 2 Properties And Manufacture Of Petroleum Asphalt 5
247.91 KB
  2.1 Definition Of Asphaltic Substances 5
  2.2 Chemical Nature 6
  2.3 Chemical Composition 9
  2.4 Physical Constitution 15
  2.5 Colloidal Characteristics 18
  2.6 Manufacture Of Petroleum Asphalt 19
  2.7 Catalytic Asphalt 28
4 3 Factors Influencing Asphalt Oxidation 35
245.26 KB
  3.1 Introduction 35
  3.2 Experimental Apparatus 36
  3.3 Method 41
  3.4 Analysis 41
  3.5 Results And Discussion 44
  3.6 Conclusions 64
5 4 Physical Changes During Catalytic Blowing Process 65
266.42 KB
  4.1 Introduction 65
  4.2 Experimental 66
  4.3 Results And Discussion 68
  4.4 Conclusions 98
6 5 Chemical Composition Blown Asphalt 99
410.05 KB
  5.1 Introduction 99
  5.2 Experimental 100
  5.3 Results And Discussion 105
  5.4 Conclusions 153
7 6 Effect Of Catalyst On Effluents 155
138.01 KB
  6.1 Introduction 155
  6.2 Experimental 155
  6.3 Results And Discussion 157
  6.4 Conclusions 170
8 7 Discussion. Conclusions And Suggestions 171
128.99 KB
  7.1 Discussion 171
  7.2 Conclusions 182
  7.3 Suggestions For Future Work 183
9 8 Appendices 185
187.58 KB
10 9 Calculations 210
34.34 KB
11 10 References 214
89.18 KB