METHOD OF MANUFACTURING REFINED PITCH

Abstract

A method of manufacturing a refined pitch includes the steps of providing a pitch and performing a heated blending process thereon to produce a pitch solution; adding an aromatic additive to the pitch solution; adding an aliphatic additive to the pitch solution; performing a quiescent sedimentation process on the pitch solution; and separating a liquid part from the pitch solution. Therefore, the method allows a concentrated mesophase pitch to be manufactured quickly and by heat processing.

Claims

1. A method of manufacturing a refined pitch, comprising the steps of: A: providing a pitch; B: providing an aromatic additive and an aliphatic additive, with the aromatic being one of anthracene and naphthalene, and the aliphatic being decane; wherein a ratio of a sum of weight of the aromatic additive and weight of the aliphatic additive to weight of the pitch is 1:1, wherein a ratio of weight of the aromatic additive to weight of the aliphatic additive is 1:0.6253; C: performing a heated blending process on the pitch to produce a pitch solution, wherein the heated blending process is performed at a control temperature of 100200 C.; D: adding the aromatic additive to the pitch solution; E: adding the aliphatic additive to the pitch solution; F: performing a quiescent sedimentation process on the pitch solution; and G: separating a liquid part from the pitch solution to obtain the pitch with less than 0.05 wt % quinoline insoluble (QI);

2. The method of claim 1, wherein the control temperature is 120180 C.

3. The method of claim 1, wherein a ratio of weight of the pitch to weight of the aromatic additive is larger than 1 but not larger than 2.5.

4. The method of claim 1, wherein a ratio of weight of the pitch to weight of the aliphatic additive is larger than 1 but not larger than 2.5.

5. The method of claim 1, wherein step C further comprises a step of blending the pitch solution continuously for a period of time, that is, 1060 minutes.

6. The method of claim 1, wherein step C further comprises a step of blending the pitch solution continuously for a period of time, that is, 2040 minutes.

7. The method of claim 1, wherein step D further comprises a step of blending the pitch solution continuously for a period of time, that is, 140 minutes.

8. The method of claim 1, wherein step E further comprises a step of blending the pitch solution continuously for a period of time, that is, 530 minutes.

9. The method of claim 1, wherein, in step F, the quiescent sedimentation process takes 60180 minutes.

10. The method of claim 1, wherein, in step F, the quiescent sedimentation process takes 100150 minutes.

11. The method of claim 1, further comprising step H of performing a vacuum distillation process on the liquid part.

12. The method of claim 13, wherein steps AH are repeated to further refine the pitch.

13. A method of manufacturing a mesophase pitch, comprising the steps of: (1) providing a pitch; (2) providing an aromatic additive and an aliphatic additive, with the aromatic being one of anthracene and naphthalene, and the aliphatic being decane, wherein a ratio of a sum of weight of the aromatic additive and weight of the aliphatic additive to weight of the pitch is 1:1, wherein a ratio of weight of the aromatic additive to weight of the aliphatic additive is 1:0.6253; (3) performing a heated blending process on the pitch to produce a pitch solution, wherein the heated blending process is performed at a control temperature of 100200 C.; (4) adding the aromatic additive to the pitch solution; (5) adding the aliphatic additive to the pitch solution; (6) performing a quiescent sedimentation process on the pitch solution; (7) separating a liquid part from the pitch solution to obtain the pitch with less than 0.05 wt % quinoline insoluble (QI); (8) performing a vacuum distillation process on the liquid part; and (9) performing a heat processing process on the liquid at a temperature of 350450 C.

14. The method of claim 13, wherein, in step (3), the heated blending process is performed at the temperature of 120180 C.

15. The method of claim 13, wherein a ratio of weight of the pitch to weight of the aromatic additive is larger than 1 but not larger than 2.5.

16. The method of claim 13, wherein a ratio of weight of the pitch to weight of the aliphatic additive is larger than 1 but not larger than 2.5.

17. The method of claim 13, wherein step (4) further comprises a step of blending the pitch solution continuously for a period of time, that is, 2040 minutes.

18. The method of claim 13, wherein step (5) further comprises a step of blending the pitch solution continuously for a period of time, that is, 530 minutes.

19. The method of claim 13, wherein, in step (6), the quiescent sedimentation process takes 100-150 minutes.

20. The method of claim 13, wherein, in step (9), the heat processing process is performed at a temperature of 380420 C.

Description

BRIEF DESCRIPTION

[0018] FIG. 1 is a schematic view of the process flow of a method of manufacturing a refined pitch according to the present invention.

DETAILED DESCRIPTION

[0019] The implement of the present invention is illustrated with specific embodiments and described below such that persons skilled in the art can easily understand the other advantages and effects of the present invention by referring to the disclosure presented hereunder.

[0020] Referring to FIG. 1, there is shown a schematic view of the process flow of a method of manufacturing a refined pitch according to the present invention. As shown in the diagram, the present invention provides a method of manufacturing a refined pitch, comprising the steps as follows:

[0021] Step A: providing a pitch and performing a heated blending process thereon to produce a pitch solution (S101). The heated blending process, which ensures that the pitch is heated beyond the softening point, is performed at a heating temperature of 100200 C., preferably 120180 C., to melt and turn the solid (at normal temperature) pitch into a liquid (at temperature above the softening point) pitch. Nonetheless, the pitch solution remains viscous even after the solid pitch has been heated beyond the softening point to become a pitch solution.

[0022] Step B: adding an aromatic additive to the pitch solution (S102). Step B entails blending the pitch solution to mix the aromatic additive and the pitch (solute) evenly. The blending process takes 1060 minutes, preferably 2040 minutes. The aromatic additive is introduced to dissolve the pitch, so as to reduce the coefficient of viscosity of the pitch and thus enhance the readiness of the pitch solution to flow. In this embodiment, the aromatic additive is coal tar oil, wash oil, anthracene, naphthalene, cetane, methyl naphthalene, or reduced oil.

[0023] Step C: adding an aliphatic additive to the pitch solution (S103). Step C aims to increase the chance that the QI in the pitch solution will coalesce to become heavier and denser. The blending process takes 140 minutes, preferably 530 minutes, such that the QI which is otherwise suspended in the pitch solution coalesce to become heavier and thus different markedly from the pitch solution in density. The aliphatic additive is kerosene, decane, or ketene.

[0024] Step D: performing a quiescent sedimentation process on the pitch solution (S104). The quiescent sedimentation process takes place while the pitch solution is idle at a temperature of 60140 C., preferably 80120 C., for 60180 minutes, preferably 100150 minutes.

[0025] Step E: separating a liquid part from the pitch solution (S105). The separation techniques for use in step E come in various forms. For example, in this embodiment, the supernatant part of the pitch solution is extracted by an extraction technique, but the present invention is not limited thereto. It is because, at this point in time, most of the QI in the pitch solution is overly dense and thus settles. Hence, the uppermost portion of the pitch solution is most thoroughly refined, thereby obtaining the pitch solution with QI content of less than 0.05 wt %. In other words, upon removal of the additives introduced in step B and step C, the pitch solution is cooled down to produce the desired pitch solution with QI content of less than 0.05 wt %. To give considerations to the yield, it is feasible to extract the pitch solution with any other related technique such that, by repeating the pitch refining steps AE, a refined pitch solution with QI content of less than 0.05 wt % is obtained.

[0026] Table 1 below shows combinations of parameters of the pitch, the aromatic additive, and the aliphatic additive. As shown in Table 1, combination No. 1 has a pitcharomatic additivealiphatic additive ratio of 1:1:0 by weight, resulting in a refined pitch with 1.81 wt % QI content and 29.3 wt % TI content. Combination No. 2 has a pitcharomatic additivealiphatic additive ratio of 4:3:1 by weight, resulting in a refined pitch with 0.76 wt % QI content and 26.9 wt % TI content. Combination No. 3 has a pitcharomatic additivealiphatic additive ratio of 2.6:1.6:1 by weight, resulting in a refined pitch with 0.01 wt % QI content and 27.7 wt % TI content, thereby indicating that the resultant refined pitch (with QI content of less than 0.05 wt %) is of high quality. Combination No. 4 has a pitcharomatic additivealiphatic additive ratio of 2:1:1 by weight, resulting in a refined pitch with 0.01 wt % QI content and 13 wt % TI content. Combination No. 5 has a pitcharomatic additivealiphatic additive ratio of 4:1:3 by weight, resulting in a refined pitch with 0.01 wt % QI content and 1.3 wt % TI content. Combination No. 6 has a pitcharomatic additivealiphatic additive ratio of 1:0:1 by weight, with the solvent being unable to dissolve the pitch, supernatant pitch liquid cannot be extracted from the pitch solution, thereby precluding the estimation of the yield, QI content, and TI content of the refined pitch.

TABLE-US-00001 TABLE 1 combinations of parameters of pitch, aromatic additive, and aliphatic additive No. Pitch:aromatic additive:aliphatic additive QI (wt %) TI (wt %) 1 1:1:0 1.81 29.3 2 4:3:1 0.76 26.9 3 2.6:1.6:1 0.01 27.7 4 2:1:1 0.01 13 5 4:1:3 0.01 1.3 6 1:0:1 N.A. N.A.

[0027] The refined pitch with low QI content undergoes heat processing for a short while to convert quickly into a concentrated mesophase pitch, thereby reducing heat processing time, manpower and costs. According to the present invention, the refined pitch indicated by No. 3 in Table 1 undergoes a heat processing process again. The heat processing process occurs at a temperature of 350450 C., preferably 380420 C., for 210 hours, preferably 48 hours. Therefore, the present invention enables a concentrated mesophase pitch to be manufactured.

[0028] The present invention is disclosed above by preferred embodiments. However, persons skilled in the art should understand that the preferred embodiments are illustrative of the features and advantages of the present invention only, but should not be interpreted as restrictive of the scope of the present invention. Hence, all modifications and changes made to the aforesaid embodiments without departing from the spirit and scope of the present invention should fall within the scope of the present invention. Accordingly, the legal protection for the present invention should be defined by the appended claims.