Optimizing an industrial-scale supercritical water gasification process requires detailed knowledge of chemical reaction pathways, rates, and product yields. Laboratory-scale reactors are employed to develop this knowledge base. The rationale behind designs and component selection of continuous flow, laboratory-scale supercritical water gasification reactors is analyzed. Some design challenges have standard solutions, such as pressurization and preheating, but issues with solid precipitation and feedstock pretreatment still present open questions. Strategies for reactant mixing must be evaluated on a system-by-system basis, depending on feedstock and experimental goals, as mixing can affect product yields, char formation, and reaction pathways. In-situ Raman spectroscopic monitoring of reaction chemistry promises to further fundamental knowledge of gasification and decrease experimentation time. High-temperature, high-pressure spectroscopy in supercritical water conditions is performed, however, long-term operation flow cell operation is challenging. Comparison of Raman spectra for decomposition of formic acid in the supercritical region and cold section of the reactor demonstrates the difficulty in performing quantitative spectroscopy in the hot zone. Future designs and optimization of continuous supercritical water gasification reactors should consider well-established solutions for pressurization, heating, and process monitoring, and effective strategies for mixing and solids handling for long-term reactor operation and data collection.

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Supercritical water gasification (SCWG) is an emerging technology with applications in renewable energy and waste processing. Environmentally benign, SCWG relies on supercritical water to decompose organic molecules. Decomposition of alcohols, aromatic compounds, carbohydrates, and amino acids was studied. Significant discrepancies in decomposition rates between batch and continuous-flow reactors exist; this review considers studies conducted with continuous-flow reactors. Intermediate and final products were identified for most decomposition reactions with good agreement between studies. Arrhenius decomposition parameters were tabulated for the data found in the literature. Due to experimental complexities and reactor limitations, most studies address a narrow range of conditions and one to few reagents. A comprehensive data set for a variety of compounds and operating conditions using a fixed reactor design has not been collected. Experimental variability results in inconsistencies in reported kinetic rates. Standardization of rate data should be considered for future studies.

A factor analysis of specific alcohol-related self-control practices reported by 410 young adults who completed a Self-control Questionnaire, consisting of both internal and external self-control measures, is described. Seven factors were extracted from the external self-control items including Rate Control, Self-reinforcement and Punishment, Alternatives, Avoidance, Limiting Driving and Cash, Controlling Time and Food, and Awareness. Three factors emerged from the internal self-control items including Impairment, Relaxation, and Anxiousness. These specific groupings of external and internal self-control variables should be empirically tested for their utility as interventions aimed at moderating the alcohol consumption of young adults.