No abstract

Brazil is the world's largest coffee producer and the second largest consumer. In 2016, the coffee crop was one of the largest in the country's history. One of the main residues of the coffee industry is coffee grounds. They are a daily waste in almost all residences, shops, bars and restaurants. The high production ends up generating an accumulation of waste due to the low processing capacity of this material. Thus, this work had the objective of finding alternative uses for this waste, to add value through the production of solid biofuel and activated biochar to remove contaminants. These bioproducts, as well as being good alternatives to minimize production waste, reduce the use of petroleum and consequently emissions of greenhouse gases. Biochar was obtained by slow pyrolysis of coffee grounds. In order to evaluate the the fuel capacity, characterization was carried out through physical-chemical analyses to measure moisture, ash, volatile material and fixed carbon contents, and elemental analysis to determine theoretical calorific value. The activated biochar was also tested as an adsorbent of organic dyes.

No abstract

Bio-oils are a complex blend of organic compounds formed by fragmentation of the structures present in biomass after undergoing a thermal process known as pyrolysis. Coffee waste is an organic residue discarded in large quantities in Brazil. This work aimed to evaluate some chemical and physicochemical characteristics of this oil, to seek economically viable uses for the product. Five pyrolysis procedures were employed and an average bio-oil yield of 18% was obtained. The oil was subjected to tests such as infrared, pour point and ash content. Infrared spectroscopy revealed an intense aliphatic character of the structure, which also had considerable presence of oxygen due to the presence of functional groups such as carbonylates, carboxylates, esters, ketones, amides and ether, as well as aromatics. The pour point determined for the bio-oil was 20° C and the ash content was less than 1%.