Microbially Mediated Rubber Recycling to Facilitate the Valorization of Scrap Tires.

The recycling of scrap tire rubber requires high levels of energy, which poses challenges to its proper valorization. The application of rubber in construction requires significant mechanical and/or chemical treatment of scrap rubber to compatiblize it with the surrounding matrix. These methods are energy-consuming and costly and may lead to environmental concerns associated with chemical leachates.

High Efficacy Two-Stage Metal Treatment Incorporating Basic Oxygen Furnace Slag and Microbiological Sulfate Reduction.

Lignocellulosic sulfate-reducing biochemical reactors (SRBRs) can be implemented as passive treatment for mining-influenced water (MIW) mitigating the potentially deleterious effects of MIW acidic pH, and high concentrations of metal(loid)s and SO. In this study, a novel two-stage treatment for MIW was designed, where basic oxygen furnace slag (slag stage) and microbial SO reduction (SRBR stage) were incorporated in series. The SRBRs contained spent brewing grains or sugarcane bagasse as sources of lignocellulose.

Biodegradation of petroleum hydrocarbons in a weathered, unsaturated soil is inhibited by peroxide oxidants.

Field-weathered crude oil-containing soils have a residual concentration of hydrocarbons with complex chemical structure, low solubility, and high viscosity, often poorly amenable to microbial degradation. Hydrogen peroxide (HO)-based oxidation can generate oxygenated compounds that are smaller and/or more soluble and thus increase petroleum hydrocarbon biodegradability. In this study, we assessed the efficacy of HO-based oxidation under unsaturated soil conditions to promote biodegradation in a field-contaminated and weathered soil containing high concentrations of total petroleum hydrocarbons (25200 mg TPH kg) and total organic carbon (80900 mg TOC kg).

Continuous-mode acclimation and operation of lignocellulosic sulfate-reducing bioreactors for enhanced metal immobilization from acidic mining-influenced water.

Lignocellulosic sulfate-reducing bioreactors are an inexpensive passive approach for treatment of mining-influenced water (MIW). Typically, microbial community acclimation to MIW involves bioreactor batch-mode operation to initiate lignocellulose hydrolysis and fermentation and provide electron donors for sulfate-reducing bacteria. However, batch-mode operation could significantly prolong bioreactor start-up times (up to several months) and select for slow-growing microorganisms.