This thesis explores the experimental and theoretical facets of the activated carbon production process in a packed bed reactor operated in counter-current configuration. Hitherto, the physical activation process for production of activated carbon involves two stages- 1. Oxidative pyrolysis (using air as the oxidizer) of biomass to produce charcoal,
2. Steam (reducing agent) activation of charcoal to synthesize activated carbon. This work attempts to develop a methodology to produce activated carbon in a self- sustainable single step process, thereby eliminating the complexity of contemporary technology. This study uses ‘air-steam’ mixture as the oxidizer. ‘Air-steam’ mixture
undergoes simultaneous gasification and activation with the biomass, converting it to activated carbon in one step.

Activated carbon (AC) is generally produced from different types of ligno-cellulosic biomass. Coconut shell is one of the widely used pre-cursors for AC synthesis due to its superior adsorption properties. The properties (Iodine value/BET surface area, yield) and techno-economics of AC produced depends on the process used. This study uses
an economical and scalable single-step physical activation process for AC synthesis with and without the use of steam in the oxidizer for activation. This thesis establishes a desirable regime for synthesizing moderate to high quality (with high yield) activated carbon from coconut shells (CS) in a batch type packed bed reactor operated in counter current mode. Identified desirable regime limits are m ̇ air 205 gm/m2 s and m ̇ steam 72 gm/m2 s. Higher activation, characterized by iodine value (IV) of about 982 mg/gm (with corresponding yield of 10.97% on wt basis) was achieved for CS (at 105-120oC) using air-steam mixture (m ̇ air- 205 gm/m2 s and m ̇ steam- 72 gm/m2 s) at 105-120oC as oxidizer. A revelation from this study is the possibility to produce moderately high quality AC in the absence of external steam in the oxidizer. AC with IV of about 772 mg/gm (corresponding yield of 12.3% on wt basis) was obtained for ’as received’ CS with 11 % moisture by wt as fuel and ambient air (m ̇ air - 205 gm/m2 s) as the oxidizer.