Mesoporous Spherical Silica Filler Prepared from Coal Gasification Fine Slag for Styrene Butadiene Rubber Reinforcement and Promoting Vulcanization

Abstract

Coal gasification fine slag (CFS) is a solid contaminant produced by an entrained flow gasifier, which pollutes fields and the air in the long term. CFS is a potential polymer reinforcement filler and has been used in polypropylene and acrylonitrile butadiene styrene resins. Coal gasification fine slag mesoporous silica (FS-SiO2) was prepared by acid leaching, calcination, and pH adjustment, with a larger specific surface area and less surface hydroxyl compared to the commercial precipitated silica (P-silica). The cure characteristics, crosslink density, mechanical properties, the morphology of the tensile fractures, dynamic mechanics, and rubber processing of the prepared styrene butadiene rubber (SBR) composites filled with P-silica and FS-SiO2 were analyzed, respectively. The results indicated that FS-SiO2 was dispersed more uniformly in the SBR matrix than P-silica owing to its smaller amount of surface hydroxyl and spherical structure, resulting in a better mechanical performance and wet skid resistance. In particular, the SBR composites with a filler pH of 6.3 exhibited the highest crosslink density and tensile strength, being superior to commercial P-silica. Significantly, the curing time decreased with the increase in the pH of FS-SiO2, which caused the rubber processing to be more efficient. This strategy can reduce the cost of rubber composites and the environmental pollution caused by CFS.

Kinetic study of mechanical and thermal properties and thermal degradation of PVC composites based on coal gasification fine slag

“…The introduction of CGFS filler into the PVC matrix generally resulted in a decrease in impact strength (see Figure 3(d)), which is likely due to the fact that the immobilization of the polymer chains by the CGFS particles may have inhibited plastic deformation, and thereby absorbed the fracture energy. 13 As a result, the tendency for crack expansion increased and the impact work decreased once the composite was subjected to an external force, thus enhancing the brittleness of the material. 26

Figure 3.Mechanical properties of PVC composites: (a) Tensile strength; (b) Elongation; (c) Flexural strength; (d) Impact strength.

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“…On the contrary, according to some reports, SiO 2 and Al 2 O 3 from CGFS do not participate in the reaction and therefore still release HCl gas during the degradation process. 13,29 At 1000 K, the amount of unburned carbon increased due to the increase in the content of inorganic filler in the matrix, so the residual mass also increased with the addition of CGFS. Since the inorganic filler was stable enough at the measured temperature, it was difficult to remove by combustion.…”

“…In addition, CGFS3 exhibited excellent performance for resin deodorization properties. Xu et al 13 CGFS mesoporous silica was prepared by acid leaching, calcination and pH adjustment, and the filled styrene-butadiene rubber composites showed better mechanical properties and resistance to wetting compared with commercial precipitated silica.…”

Mechanical activation of coal gasification fine slag and mechanical and thermal properties of coal gasification fine slag–poly(vinyl chloride) composites

“…With the increasingly strict quality requirements within the coal chemical industry and the 'dual carbon' target, [12] the utilization of CGFS has become one of the most important factors limiting developments within the coal chemical industry. At present, the more common uses of gasification slag are related to the production of adsorbents [13][14][15], construction materials [16][17][18], soil improvement [19][20][21], and the production of PVC composite materials using the CGFS as a filler (applications for tubes, sheets, profiles, etc) [22][23][24]. Considering both its technical feasibility and economic viability, the production of composite materials represents a more efficient and higher-quality utilization of CGFS.…”

Effect of Alkali Fusion Methods on the Preparation of One-Part Geopolymer From Coal Gasification Slag

“…Coal gasification is a process that uses oxygen or water vapor to react with coal at high temperatures to produce valuable gas while producing a large amount of coal gasification slag. , With the development of the coal gasification industry, large-scale coal gasification slag has brought a series of prominent environmental problems, which will occupy many land resources and risk groundwater pollution. − Approximately 33 million tons of coal gasification slag are produced annually in China . With the development of coal chemical enterprises, it can be predicted that more coal gasification slag will be produced in the near future.…”