Solvothermal chemistry is widely applied in research laboratories as well as industry, entailing significant consumptions of organic solvents every year. Yet, there is a very poor understanding of the internal reaction chemistry in solvents under such non-ambient conditions and the organic by-products they incur. This study has sought to elucidate trends in by-product formation under continuous-flow conditions for a range of the most commonly used solvents: Methanol, ethanol, isopropanol, ethylene glycol, acetone and toluene. The impact of binary mixtures (co-solvents) has been studied for the two cases (i) acetone-ethanol and (ii) ethanol-toluene. Additionally, the effect of solvothermal nanoparticle synthesis has been investigated, employing the specific cases of Pt, PtRu (alloy) and Ru metal nanoparticles produced from Pt(acac)2 and Ru(acac)3 precursors in an ethanol/toluene mixture. Finally, the impact of switching to a different reactor system has been tested for three solvents: Ethanol, isopropanol and acetone. All experiments were carried out as flow syntheses. The series were temperature resolved in the 100-450 degrees C range. By-products have been characterized and selectively quantified by MS and GC-MS. Reaction pathways are unraveled and given for all identified by-products in all solvents and binary mixtures. Quantifications shows conversion rates up to 8.14wt% of the solvents and formation up to 190 by-products. The intent of this study is to provide a "manual" for the field of solvothermal chemistry which can guide choices between solvents and/or reaction temperatures. Also, it may afford better evaluations of "green footprints" i.e. improve existing and future sustainability analyses in the field. (C) 2016 Elsevier B.V. All rights reserved.