Improved Fermentative Hydrogen Production with the Addition of Calcium-Lignosulfonate-Derived Biochar

Abstract

This study investigated the roles of calcium lignosulfonate (CL) and its derived biochar (BC) in biohydrogen production. CL was pyrolyzed at 250 °C to produce BC, and the main characteristics of the two materials were compared. A series of anaerobic processes were carried out at 54 ± 1 °C, and the results suggested that CL remarkably lowered the H 2 yield compared with that obtained with CL-derived BC. The highest H 2 yield (262 mL/g glucose) was obtained at 20 g/L, corresponding to an increase of 50.9%, whereas the lowest H 2 yield (110 mL/g glucose) occurred at 20 g/L and was 36.4% lower than that in the control group (173 mL/g glucose, without CL and BC). The CL-derived BC exhibited more pore structures than CL, providing more attachment sites for anaerobes. In addition, the high potassium, calcium, and magnesium contents and low sulfur dosage enhanced the microbial activity and process stability.

Facile Fabrication of Calcium-Doped Carbon for Efficient Phosphorus Adsorption

“…During the CL pyrolysis process, CaCO 3 within CLDC800 partly decomposed CaO at 800 °C, producing a peak at 53.8°associated with CaO. 24 The peak near 28°( 3.36 nm) further confirmed the presence of CaCO 3 in CLDC400, as also confirmed by Wang et al 35 and Zhao et al 28 During the CL carbonization process, the two groups of CO 3 2− and Ca 2+ were produced, and they could interact together and form CaCO 3 . Interestingly, CLDC400 contained the −OH and −CO (−COOH) substituents necessary for P adsorption.…”

“…27 It can be feasible to recover CL from waste liquor, but CL removal is usually low. 28 Currently, there are few reports on BC production with low-molecular-weight lignin (e.g., CL). 28 Zhao et al 28 investigated improved biohydrogen production with BC produced at 250 °C, but they did not further study high-temperature (over 400 °C) BC products from CL for other applications.…”

“…CL contains a hydrophilic sulfonic acid group and forms a spherical three-dimensional network . It can be feasible to recover CL from waste liquor, but CL removal is usually low . Currently, there are few reports on BC production with low-molecular-weight lignin (e.g., CL) .…”

Biohydrogen Production Amended with Nitrogen-Doped Biochar

“…Certain functional groups on the BC surface acted as pH buffers during H 2 production. Appropriate amounts of VFAs could create moderate pH conditions (4.5–6.0), facilitating H 2 -producing bacterial growth and thus generating high H 2 yields. , H 2 is rapidly produced along the formate and HAc pathways, but low-carbon VFA accumulation could lead to a quick decrease in the process pH, resulting in toxic effects on the microbes. Subsequently, butyrate-type evolution generally becomes dominant, which diminishes the superfluous H + and enhances stable H 2 generation.…”

CO2 and Steam-Assisted H2 Separation through BaCe0.8Y0.2O3−δ–Ce0.8Y0.2O2−δ Hollow Fiber Membranes

“…Mixed protonic and electronic conducting (MPEC) membranes have received great attention over the past few decades as a result of their potential applications in hydrogen pumps, catalytic membrane reactors, hydrogen sensors, fuel cells, etc. − Hydrogen is a kind of clean energy carrier and expected to be one of the main energy sources in the near future. − Hydrogen separation is the key step for its production and becomes one of the most important applications for MPEC membranes. − A large number of studies about the electrical properties, stability, and hydrogen permeability of MPEC membranes based on BaCeO 3 or SrCeO 3 perovskite oxides had been performed in the past few decades. − Despite significant progress in the development of MPEC membranes, the hydrogen permeability is still lower than required for industrial applications. Improving the H 2 permeation flux is still the main subject for MPEC membranes.…”