Responses in sediment phosphorus and lanthanum concentrations and composition across 10 lakes following applications of lanthanum modified bentonite

A combined field and laboratory scale study of 10 European lakes treated between 2006 and 2013 with a lanthanum (La) modified bentonite (LMB) to control sediment phosphorus (P) release was conducted. The study followed the responses in sediment characteristics including La and P fractions and binding forms, P adsorption capacity of discrete sediment layers, and pore water P concentrations. Lanthanum phosphate mineral phases were confirmed by solid state 31P MAS NMR and LIII EXAFS spectroscopy. Rhabdophane (LaPO4 · nH2O) was the major phase although indications of monazite (LaPO4) formation were also reported, in the earliest treated lake. Molar ratios between La and P in the sediments were generally above 1, demonstrating excess La relative to P. Lanthanum was vertically mixed in the sediment down to a depth of 10 cm for eight of the ten lakes, and recovery of La in excess of 100% of the theoretical aerial load indicated translocation of the LMB towards the deepest areas of the lakes. Lanthanum was generally recovered from bed sediment samples following sequential chemical extraction from the HCl fraction. Soluble reactive P (SRP) release experiments on intact sediment cores indicated conditions of P retention (with the exception of two lakes) by sediments, indicating effective control of sediment P release, i.e. between two and nine years after treatment

Hydrothermal Liquefaction of Dried Distillers Grains with Solubles: A Reaction Temperature Study

The effect of the reaction temperature on hydrothermal liquefaction of dried distillers grains with solubles (DDGS) was investigated using a novel stop-flow reactor system at varying temperatures (300–400 °C), fixed pressure (250 bar), and fixed reaction time (15 min). The stop-flow reactor provides rapid heating of biomass feeds and the option of performing multiple sequential repetitions. This bypasses long, uncontrollable temperature gradients and unintended changes in the reaction chemistry. The product, a crude bio-oil, was characterized in terms of yield, elemental composition, and chemical composition. Higher reaction temperatures resulted in improved bio-oil yields, less char formation, and higher heating values of the bio-oil. A supercritical reaction temperature of 400 °C was found to produce bio-oil in the highest yields and of the best quality

Atmospheric Degradation of Amines (ADA) : summary report from atmospheric chemistry studies of amines, nitrosamines, nitramines and amides.

CLIMIT project no. 20812