Study on the preparation and production factors of a direct lignocellulose biomass fuel cell

Lignocellulose-Based Superabsorbent Polymer Gel Crosslinked with Magnesium Aluminum Silicate for Highly Removal of Zn (II) from Aqueous Solution

Lignocellulose (LCE) was ultrasonically treated and intercalated into magnesium aluminum silicate (MOT) clay to prepare a nano-lignocellulose magnesium aluminum silicate polymer gel (nano-LCE-MOT) for the removal of Zn (II) from aqueous solution. The product was characterised using nitrogen adsorption/desorption isotherm measurements, Fourier-transform infrared spectroscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The conditions for the adsorption of Zn (II) on nano-LCE-MOT were screened, and adsorption kinetics and isotherm model analysis were carried out to explore the adsorption mechanism and achieve the optimal adsorption of Zn (II). Optimal adsorption was achieved at an initial Zn (II) concentration of 800 mg/L at 60 °C in 160 min at a pH of 4.52. The adsorption kinetics were explored using a pseudo-second-order model, with the isotherm adsorption equilibrium found to conform to the Langmuir model. The maximum adsorption capacity of the nano-LCE-MOT polymer gel toward Zn (II) is 513.48 mg/g. The materials with adsorbed Zn (II) were desorbed using different media, with HCl found to be the most ideal medium to desorb Zn (II). The optimal desorption of Zn (II) was achieved in 0.08 mol/L HCl solution at 65 °C in 60 min. Under these conditions, Zn (II) was almost completely desorbed from the adsorbents, with the adsorption effect after cycling being slightly different from that of the initial adsorption.

Raw biomass electroreforming coupled to green hydrogen generation

Despite the tremendous progress of coupling organic electrooxidation with hydrogen generation in a hybrid electrolysis, electroreforming of raw biomass coupled to green hydrogen generation has not been reported yet due to the rigid polymeric structures of raw biomass. Herein, we electrooxidize the most abundant natural amino biopolymer chitin to acetate with over 90% yield in hybrid electrolysis. The overall energy consumption of electrolysis can be reduced by 15% due to the thermodynamically and kinetically more favorable chitin oxidation over water oxidation. In obvious contrast to small organics as the anodic reactant, the abundance of chitin endows the new oxidation reaction excellent scalability. A solar-driven electroreforming of chitin and chitin-containing shrimp shell waste is coupled to safe green hydrogen production thanks to the liquid anodic product and suppression of oxygen evolution. Our work thus demonstrates a scalable and safe process for resource upcycling and green hydrogen production for a sustainable energy future.

The scale-up of the coupling of water electroreduction (HER) with organic electrooxidation remains challenging. Here the authors address this challenge by coupling HER with electrooxidation of raw biomass chitin, cogenerating acetate and green hydrogen safely at high current density.

Lignocellulose, Cellulose and Lignin as Renewable Alternative Fuels for Direct Biomass Fuel Cells

In recent years the use of renewable sources, such as lignocellulosic biomass (LCB), as the fuel for various types of fuel cells received growing interest. Different types of fuel cells, that is, operated at low temperatures (T<100 °C; microbial fuel cells (MFC), alkaline (AFCs) and flow fuel cells (FFCs)), intermediate temperatures (T in the range 150-300 °C, proton-conducting inorganic-organic composite membrane fuel cells), and high temperatures (T≥500 °C, direct carbon fuel cells (DCFCs)), have been used for the conversion of the chemical energy in LCB to electrical energy. The economic advantage of the direct use of LCB consists of avoiding the acid hydrolysis of cellulose to glucose for low-temperature fuel cells and the pretreatment at high temperatures necessary to convert biomass to biochar (pyrolysis) in the case of high-temperature fuel cells. In this Review, the characteristics of direct biomass fuel cells are presented and their performance is compared with that of indirect biomass fuel cells fed with glucose (low-temperature fuel cells) and biochar (high-temperature fuel cells).

Recent advances in the electrooxidation of biomass-based organic molecules for energy, chemicals and hydrogen production

The recent developments in biomass-derivative fuelled electrochemical converters for electricity or hydrogen production together with chemical electrosynthesis have been reviewed.