The optical
thin slices for microscopic
optical analysis were prepared according to GB/T 16773–2008.
The samples were mixed with an epoxy resin in ring-shaped molds. Once
cured, the sample was demoulded, ground, and polished to obtain an
optical thin slice with a surface size of 25 mm × 25 mm. The
sample particle area on the working area should be more than 2/3.
The petrographic analysis of the optical thin slices was performed
using a Zeiss microscope (Axio Scope1&MSO) with reflected light,
50× magnification, and oil immersion. The petrographic composition
of coal and coke based on the microscopic composition was determined
according to the ICCP guidelines.27 (link)−29 (link) According to the classification scheme for the combustion
coal, the morphology of the unburned char was characterized.30 (link) The quantitative studies were carried out using
point counters; the maceral content analysis was carried out on the
surface of the optical thin slices with equal spacing points, and
the effective points of each optical slice were not less than 500.
thin slices for microscopic
optical analysis were prepared according to GB/T 16773–2008.
The samples were mixed with an epoxy resin in ring-shaped molds. Once
cured, the sample was demoulded, ground, and polished to obtain an
optical thin slice with a surface size of 25 mm × 25 mm. The
sample particle area on the working area should be more than 2/3.
The petrographic analysis of the optical thin slices was performed
using a Zeiss microscope (Axio Scope1&MSO) with reflected light,
50× magnification, and oil immersion. The petrographic composition
of coal and coke based on the microscopic composition was determined
according to the ICCP guidelines.27 (link)−29 (link) According to the classification scheme for the combustion
coal, the morphology of the unburned char was characterized.30 (link) The quantitative studies were carried out using
point counters; the maceral content analysis was carried out on the
surface of the optical thin slices with equal spacing points, and
the effective points of each optical slice were not less than 500.
