Graphene’s excellent electrical, mechanical, thermal and optical properties make it one of the most desirable materials for diverse applications. Nevertheless, mass producing graphene has been a challenge since the first discovery in 2004. Here, we conducted a fast, green and safe method: multi-step thermal reduction (MSTR) process combining the use of commercial microwave and conventional furnace as the first and second steps, respectively to reduce graphene oxide (GO). Both steps used common tools in a short time to minimise investment. By evaluating several characterisation methods, we show that the first step partially reduces GO by decomposing most hydroxyls, creating a double interlayer spacing distance of 9.381 Å and 3.590 Å with retained hydrophilic property. Meanwhile, the second step further decomposes oxygen functional groups, recovers structural defects and creates a porous layered structure with an average interlayer spacing distance of 3.504 Å, 3.413 Å and 3.393 Å for temperatures of 500, 650 and 800 °C, respectively. In short, MSTR is a viable option to mass produce graphene-based material with desired properties.

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Failure analysis of the petrochemical plant’s bank-wall side boiler tube has been conducted to determine the root cause of tube failure. The tube material is low carbon steel ASTM A178 grade A. Visual examinations of the cracked surface revealed that the fractured surface is flat, without plastic deformation, and several longitudinal and transverse fissures are present. The SEM and optical microscope examinations show that the cracks were intergranular and transgranular. A hydrogen attack caused the intergranular crack, and thermal fatigue produced the transgranular crack. Boiler tube failure was caused by a steam blanket on the sloping tube’s top inner diameter that induced iron oxide deposition and accumulation. Hydrogen was produced after a chemical reaction at the deposit-metal interface between the iron oxide deposit and ingress steam. Local temperature variation on the top part of the sloped tube occurred during the splashing and evaporation of water, promoting thermal fatigue.