Static and Dynamic Investigations on Leaching/Retention of Nutrients from Raw Poultry Manure Biochars and Amended Agricultural Soil

Biochar from date palm (Phoenix dactylifera L.) residues—a critical review

Biochar, a carbon rich organic amendment, derived from organic biomass by pyrolysis under high-temperature and zero oxygen condition, is a soil amendment to enrich soil with essential nutrients. Biochar is multidimensional in its benefits, including increase in soil carbon sequestration, reduction in green house emission, improved soil fertility, and prolonged soil moisture retention capability to overcome drought. Biochar can be produced from a wide array of biological residues, contributed by plants as well as animals. Date palm a common plant in Gulf region, leave enormous quantity of residues, which are disposed or burnt as waste in farms, that acts as a source of pollution in date-producing nations. The residual biomass from dates is utilized in cattle feed production in some countries. Disposing these residues without harming the environment is a challenge and the perfect solution is biochar. Based on the unique abatement potential of biochar and its functions to improve soil health and soil carbon sequestration, biochar can be considered as long-term agriculture adaptation strategy. This comprehensive review highlights the production of biochar from date palm biomass, the influence of different date palm parts in biochar production, and their potential benefits to the community. It is realized that the knowledge of biochar from date palm residues is still in its infancy which requires concerted efforts to educate the date palm farming community to utilize the valuable biomass from date palm for transformation to a nutritious and eco-friendly product, biochar.

Conversion of Industrial Sludge into Activated Biochar for Effective Cationic Dye Removal: Characterization and Adsorption Properties Assessment

This paper presents an in-depth characterization of a raw industrial sludge (IS-R) and its KOH-activated biochar pyrolyzed at 750 °C (IS-KOH-B) followed by their application to remove a cationic dye from aqueous solution. Materials characterization shows that compared to the IS-R, the IS-KOH-B has improved structural, textural, and surface chemical properties. In particular, the IS-KOH-B’s BET surface area and total pore volume are about 78 and 6 times higher than those found for the IS-R, respectively. The activated biochar efficiently retained the cationic dye under wide experimental conditions. Indeed, for an initial dye concentration of 50 mg L−1, removal yields were assessed to be more than 92.5%, 93.5%, and 97.8% for a large pH range (4–10), in the presence of high contents of competing cations (3000 mg L−1 of Ca2+, Mg2+, Na+, and K+), and a low used adsorbent dose (1 g L−1), respectively. The Langmuir’s adsorption capacities were 48.5 and 65.9 mg g−1 for of IS-R and IS-KOH-B, respectively, which are higher than those reported for various adsorbents in the literature. The dye removal was found to be monolayer, spontaneous, and endothermic for both the adsorbents. Moreover, this removal process seems to be controlled by chemical reactions for IS-KOH-B whereas by both physico–chemical reactions for IS-R. This study demonstrates that the raw industrial sludge and especially its KOH-activated derived biochar could be considered as promising adsorbents for the removal of dyes from aqueous solutions.

Olive Mill by-Products Thermochemical Conversion via Hydrothermal Carbonization and Slow Pyrolysis: Detailed Comparison between the Generated Hydrochars and Biochars Characteristics

In this research work, an ecofriendly approach was adopted for the treatment of two abundant liquid and solid agricultural wastes generated by olive mill industry: olive mill wastewater (OMWW) and raw olive pomace (ROP). It consists, firstly of the impregnation of ROP by OMWW and the conversion of the resulting impregnated sample (IROP) into hydrochars and biochars through hydrothermal carbonization (HTC) and slow pyrolysis methods, respectively. The impact of the treatment temperature on the physico-chemical properties of the derived chars was assessed by various analytical techniques. The hydrochars production yields were found to be higher than the biochars ones and associated to the lower temperature used. However, the generated biochars possess higher carbon percentage and lower volatile matter contents. In addition, the increase of the hydrothermal and pyrolysis carbonization temperatures shows an increase of macro-elements contents and a significant decrease of the O/C ratios which led to an enhancement of the high heating value for both hydrochars and biochars. The FTIR and Boehm titration analysis highlighted a significant alteration of the biochars surface chemistry compared to hydrochars evidenced by the lower amount of functional groups. The collected data emphasize on the efficient potential application of hydrochars and biochars for agricultural and environmental applications, respectively. Furthermore, it was noted that both chars have high energetic potentials and could be used for co-firing with coal in industrial boilers.

Waste Strategies Development in the Framework of Circular Economy

Current studies proposed that more that 2bn tons of solid waste/year are produced globally [...]