**1. Introduction**

Activated carbon (AC), no wonder, is regarded as a wonder-material since it is a very vital active material in scores of applications such as catalytic supports, removal of pollutants, electrodes for battery and capacitors, gas storage etc., and these applications require carbon powders with specific functionalities like surface area, chemical constituents, pore structure etc. Since last decade, materials scientists are attracted towards biomass and more specifically, phytomass which have the source from the mass (biomass) of living and dead plants for producing

value-added materials. It is interesting to note that a total of 82% of the biomass is of plant origin and crop residues include more than half of the world's agricultural phytomass [1]. Moreover, a study indicate that the annual global production of wood-derived biomass is around 4.6 Gt out of which 60% is utilized for energy production, 20% for industrial 'round wood' manufacture and the remaining 20% will be primary production loss that remains in-field to decay. Further an estimated 80% of forest tree mass is being lost as waste [2]. Generally it is known that starch, cellulose, hemicellulose, fructose, glucose, amino acids, lignins, lipids, organics, inorganics etc. are the chief constituents of phytomass [3] and thus they are apparently rich in carbon content for producing AC powders and are deemed to be low-cost alternative for commercial carbons hitherto utilized for the above-said applications. Obviously, the omnipresent and plentiful agricultural discards effectively offer a secondary, inexpensive and renewable source of carbon. Having seen the basic information on phytomass, it is also pertinent to understand the present scenario of the landfills which have already become flooded with non-treatable garbage and that they do not admit solid-wastes anymore and consequently, we propose ways of segregating, recycling/up cycling/reuse of wastes for reducing disposal problems and improving a Nation's economy or in other words, "waste valorization", the processes of treating wastes for beneficial use that may reduce pollution and the concomitant environmental impacts, has now been developed into a trending research among materials advocates. Also, considering the production cost of materials/products, environmental and energy concerns, the process of reuse of phytomass wastes to generate value-added products is of dire need. Simultaneously, huge economy involved in the clearing-off the (phytomass) wastes globally has activated many research groups to recycle various categories of wastes to achieve value-added products by which the current energy emergency may possibly be mitigated. Thus waste phytomass should be seen as unexplored resources as well as zero-cost source of essential environmental services and not as wastes at all. Hence the production of AC materials, especially from these cheap and natural bio-precursors is a highly attractive research theme in the science of functional materials. Consequently this chapter has been planned to provide recycling based content having a great potential in reducing environmental impact, climatic issue and initiate circular bio-economy model. So this chapter has been designed as a review and summarize the key research reported on six interesting applications where the various zero-cost (waste) phytomass had served as the precursors for producing low-cost ACs. For consistency, the chapter has been sectioned individually under the following headlines based on the applications of phytomass-derived environmental friendly AC as;


Initially, certain fundamental aspects of AC are also quickly presented for the benefit of the readers. Hence the fundamental research results discussed in the

#### *Phytomass-Derived Multifunctional Activated Carbon as a "Wonder-Material"… DOI: http://dx.doi.org/10.5772/intechopen.99448*

chapter would not only exemplify the multi-dimensional features and applications of phytomass-derived AC but also hints the variety and variability in carbon sources available and break through the conventional idea of obtaining high-performing active carbon too.
