Novel highly integrated biodiesel production technology in a centrifugal contactor separator device

The base catalyzed production of biodiesel (FAME) from sunflower oil and methanol in a continuous centrifugal contactor separator (CCS) with integrated reaction and phase separation was studied. The effect of catalyst loading (sodium methoxide), temperature, rotational frequency and flow rates of the feed streams was investigated. An optimized and reproducible FAME yield of 96% was achieved at a feed rate of 12.6mLmin−1 sunflower oil and a sixfold molar excess of MeOH (3.15mLmin−1) containing the catalyst (1 wt% with respect to the oil). A jacket temperature of 75 °C and a rotational frequency of 30 Hz were applied. The productivity under those conditions (61 kgFAMEm−3liquid min−1) was slightly higher than for a conventional batch process. The main advantage is the combined reaction–separation in the CCS, eliminating the necessity of a subsequent liquid–liquid separation step.

Recovery of acetic acid from an aqueous pyrolysis oil phase by reactive extraction using tri-n-octylamine

The application of reactive extraction to isolate organic acids, particularly acetic acid, from the aqueous stream of phase splitted pyrolysis oil using a long chain aliphatic tertiary amine is reported. Acetic acid recovery was optimized by selecting the proper amine and diluent combination and adjustment of the process conditions. The best results were obtained with tri-n-octylamine (TOA) in 2-ethyl-hexanol (40 wt%) with 84% acetic acid recovery at equilibrium conditions (room temperature). Other organic acids present in the feed (formic acid and glycolic acid) were also co-extracted (92% and 69% extraction efficiencies), as well as relatively non-polar compounds like substituted phenolics and ketones. The continuous reactive extraction process was successfully demonstrated in a centrifugal contactor separator (CCS) device, and acetic acid recoveries of 51% and 71% were obtained in a single CCS device and a two stage cross currently operated cascade, respectively.

Catalytic hydrogenation of levulinic acid to ɣ-valerolactone: Insights into the influence of feed impurities on catalyst performance in batch and flow

γ-Valerolactone (GVL) is readily obtained by the hydrogenation of levulinic acid (LA) and is considered a sustainable platform chemical for the production of biobased chemicals. Herein, the performance and stability of Ru-based catalysts (1 wt % Ru) supported on TiO 2 (P25) and ZrO 2 (monoclinic) for LA hydrogenation to GVL is investigated in the liquid phase in batch and continuous-flow reactors using water and dioxane as solvents. Particular attention is paid to the influence of possible impurities in the LA feed on catalyst performance for LA hydrogenation. Benchmark continuous-flow experiments at extended times on-stream showed that the deactivation profiles are distinctly different for both solvents. In dioxane, the Ru/ZrO 2 catalyst is clearly more stable than Ru/TiO 2, whereas the latter is slightly more stable in water. Detailed characterization studies on spent catalysts after long run times showed that the deactivation of Ru/TiO 2 is strongly linked to the reduction of a significant amount of Ti 4+ species of the support to Ti 3+ and a decrease in the specific surface area of the support in comparison to the fresh catalyst. Ru/ZrO 2 showed no signs of support reduction and displayed morphological and structural stability; however, some deposition of carbonaceous material is observed. Impurities in the LA feed such as HCOOH, H 2SO 4, furfural (FFR), 5-hydroxymethylfurfural (HMF), humins, and sulfur-containing amino acids impacted the catalyst performance differently. The results reveal a rapid yet reversible loss of activity for both catalysts upon HCOOH addition to LA, attributed to its preferential adsorption on Ru sites and possible CO poisoning. A more gradual drop in activity is found when cofeeding HMF, FFR, and humins for both solvents. The presence of H 2SO 4, cysteine, and methionine all resulted in the irreversible deactivation of the Ru catalysts. The results obtained provide new insights into the (ir)reversible (in)sensitivity of Ru-based hydrogenation catalysts to potential impurities in LA feeds, which is essential knowledge for next-generation catalyst development