Functionalized Activated Carbon Derived from Biomass for Photocatalysis Applications Perspective

Table 2

Catalytic approach on conversion of cellulose to carbon based materials.

Categories	Types	Advantages
Homogeneous	Ionic liquid; (e.g.: [BMIM]Cl; [EMIM]Cl and [EMIM]BF4)	(i) Low melting point; (ii) Appears as crystal in normal condition; (iii) Acts as template on production of porous carbon structure; (iv) Solvent reaction media; (v) High yield of carbon production
Heterogeneous	Solid acid catalyst; (i) Bronsted/Lewis solid acid; (e.g.: ZrP; SiO2-Al2O3, WOX/ZrO2, c-Al2O3,); (ii) HPA; (e.g.: H3PW12O46; H4SiW12O40; Cs2.5H0.5PW; Cs2.5H0.5PW2O40)	(i) High catalyst selectivity; (ii) Good separation process; (iii) High promotion on depolymerization of cellulose; (iv) Low formation of soluble oligomer; (v) Low cellulose self-hydrolysis; (vi) Favors direct formation of lactic acid; (vii) High stability
Heterogeneous	Ion exchange resin; (e.g.: Amberlyst; McM-41; HnbM0O6; mixed oxides; niobic acid; silica-niobic; niobium phosphate)	(i) High accessibility of saccharides; (ii) Satisfactory reaction rate
Heterogeneous	Zeolite; (e.g.: ZSM-5; Beta; Mordenite; Ferrient; FCC; Al-MCM-42; SBA-15; Al-MSU-F; MOR)	(i) High selectivity to adsorb molecules; (ii) Good separation process; (iii) Good thermal and hydrothermal stabilities; (iv) Production of porous carbon
Heterogeneous	Metal ions; (e.g.: Cr^3+; Mn^2+; Fe^3+; Fe^2+; Co^2+)	(i) Good catalyst for ring opening and hydrogenation cellulose; (ii) Require short reaction time; (iii) High yield of glucose; (iv) High turnover amount of catalyst; (v) High activity and selectivity; (vi) Good recyclability; (vii) Easily separable
Heterogeneous	Metal oxide; (e.g.: HnbM0O6; Al2O3)	(i) Green process; (ii) Nonvolatility; (iii) Highly stable; (iv) Nontoxic; (v) Reusability; (vi) Low cost