In this study, graphene oxide (GO) was synthesized by the improved Hummers’ method. The degree of oxidation from graphite (Gi) to GO was determined through interlayer spacing calculated from X–ray diffraction. Besides, the effect of KMnO4: Gi ratios (X1), H2SO4 volume (X2), oxidation temperature (X3), oxidation time of stage 1 (X4), and oxidation time of stage 2 (X5) was screened by the Plackett–Burman model. The simultaneous impact of three factors that influenced the degree of oxidation (X1, X2, and X3) was studied by the Box–Behnken experimental model of response surface methodology to achieve suitable conditions for the GO synthesis process. The characterization of GO product was investigated via the modern analytical methods: X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, UV–Vis spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. Inaddition, the study was also carried out on a pilot scale for orientation in industrial application with the yield of 14 g/batch.

Two-component polyurethane flame-retardant coatings were prepared by blending trichloro aromatic modified polyesters(TCMPs) and polyisocyanate. TCMPs were synthesized by polycondensation of trichlorobenzoic acid(TCBA), a flame-retardant component, with adipic acid, 1,4-butanediol, and trimethylolpropane. The content of TCBA was varied in 10, 20, and 30 wt% for the reaction. These new flame-retardant coatings showed various properties comparable to other non-flame-retardant coatings. Moreover, we carried out the combustion test and the flammability test for our flame-retardant coatings. The results of vertical burning test for the coatings containing more than 20 wt% of TCBA were determined as 'no burn'. The results of flammability test for the coatings with 20 wt% and 30 wt% of TCBA contents indicated the limiting oxygen index(LOI) values of 25% and 28% respectively, which implied relatively good flame retardancy.

This work presents an experimental study of the influence of lifting velocity on cake formation during filtration. For design of hot gas cleanup system using ceramic filter reactor, the most important consideration is coating conditions of sorbent in filter surface (for example : lifting velocity, coating weight of sorbent, pulsing interval and removal effect for dechlorination and desulfurization). We studied the optimum operation condition as paticle size and lifting velocity using a ceramic filter reactor at 550oC. Based on the results obtained during cold and hot test, optimum lifting velocity in a ceramic filter reactor was selected 0.68 m/s. Also, the removal behaviour of the ceramic filter during filtration was studied using differential pressure. Optimum removal efficiency for dechlorination and desulfurization accomplished at differential pressure condition over 74 mmH2O.