*1.2. Purpose of Study*

Several studies reported the pelleting of di fferent types of biomass and their blends, with most of the studies focusing on material and process parameters including the mechanism of bonding from di fferent viewpoints [2,23–27]. Despite the numerous studies, the exact mechanism involved in bonding in biomass pellets and the source of inter-particle bonding relevant to pellet quality are not fully understood and still a subject of debate, particularly when the pellets are made from a blend of two or more di fferent biomass materials. Not much was undertaken, in terms of research, to study and establish, from a structural chemistry perspective, di fferences in the mechanism of bonding between pure and blended biomass pellets relevant to the production of good-quality pellets. Investigations of this sort require a systematic approach that takes into account the use of state-of-the-art analytical techniques that can go beyond standard tests and visual assessments. The techniques must be able to provide information beyond what can be visualized by the human eye and o ffer evidence of quality without having to rely on special quality assessment tools. Therefore, this study aims to investigate and establish di fferences in the mechanism of bonding, relevant to quality, between pure and blended pellets made from Norway spruce and pea starch, relying on molecular, microscopic, and thermal analyses provided through the use of advanced analytical instruments able to o ffer information beyond what can be visualized by the naked eye.

The choice of the materials used in the study, the reason for blending, and the blend ratio are explicitly described in the section below.
