Hydrogen generation by water electrolysis using carbon nanotube anode

Electro-hydrolysis of cheese whey solution for hydrogen gas production and chemical oxygen demand (COD) removal using photo-voltaic cells (PVC)

“…Initially the gas phase was mainly i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 1 5 8 4 1 e1 5 8 4 9 composed of H 2 and CO 2 without methane due to dark fermentation of carbohydrates producing VFAs and CO 2 . However, hydrogen concentration in the gas phase increased to 98% after two days of operation due to hydrogen gas formation by reaction (3). Hydrogen percentage in the gas phase also increased with increases in initial COD concentration and reached the highest level (99.9%) for the initial COD of 35172.16 mg L À1 at the end of operation due to high volumes of H 2 gas formation at high COD and VFA concentrations with no CO 2 formation (eqn (3)).…”

“…Table 3 also summarizes weight losses from the electrodes due to Al(III) release to the solution during electro-hydrolysis. Released Al(III) ions can be removed from the solution by precipitation in form of Al(OH) 3 with the addition of lime (Ca(OH) 2 ) solution followed by filtration.…”

“…Fermentative hydrogen gas production from renewable resources such as biomass is less energy intensive but is not economically feasible due to low rates and yields of H 2 gas production [1,2]. Hydrogen gas production by water electrolysis has been extensively investigated and reported in literature [3,4]. The net energy balance for water electrolysis is negative due to larger energy requirement for electrolysis of water (4 kWh m À3 H 2 ) as compared to the energy content of hydrogen gas (3.55 kWh m À3 H 2 ).…”

Mesoporous Carbons for Energy-Efficient Water Splitting to Produce Pure Hydrogen at Room Temperature

“…This process was first proposed and demonstrated by Coughlin and Farooque [9,10] and developed more fully in the recent investigations of Seehra et al using a variety of carbons and termed as carbonassisted water electrolysis (CAWE) [11,12]. Some follow-up studies of this process have been reported by Dubey et al [13] using a carbon nanotube anode and by Giddy et al [14] using a solid-state electrolytic cell. A different variation of this process involving hydrogen generation by laser irradiation of a carbon powder suspension in water has been reported by Akimoto et al [15].…”

Nanoporous oxide coatings on stainless steel to enable water splitting and reduce the hydrogen evolution overpotential

“…Water electrolysis can generate high purity hydrogen and oxygen and, if coupled with other renewable energy systems, is environmentally friendly. Also, it does not require large, centralized plants and the cost of hydrogen production scales well from smaller to larger systems [6]. However, in order to make this process more efficient and cost effective, further improvements in low cost electrode materials having low overpotentials are desirable goals.…”