

įor production of biochar there can be virtually used all types of biomass: sewage sludge, residues from the agricultural and food industries (e.g., rice husks, cotton stalks and nut shells, soybean husks, winter wheat at full maturity (grains and straw were pyrolyzed separately) and meadow grass, maple leaf, banana peels, cocoa tree ( Gliricidia sepium) biomass, wastes of date palm and oil palm shell, cork wastes, microalgae ( Spirulina sp.) and macroalgal ( Eucheuma spinosum) biomass ), energy plants (e.g., corn cobs, poplar ( Populus), willow ( Salix) ) and raw materials of forest origin (e.g., tree bark ), eucalyptus residues, sphagnum moss, mature acorns ( Quercus pubescens) and mature cypress cones ( Cupressus sempervirens pyramidals), pine cones, larch cones ( Larix decidua Mill. Taking into account a wide range of available biomaterial wastes and different production techniques, a great variety of physicochemical properties of the obtained biochars should be expected. In addition, the properties of biochar are also influenced by the type of raw material from which it was obtained. High pyrolysis temperature often increases the surface area and the carbonized fraction which leads to a large adsorption capacity. The characteristics of biochar are largely dependent on the carbonization conditions. Moreover, biochars are highly carbonized materials and therefore they possess a great calorific value, comparable to that of high-rank coals.

It is characterized by a large number of surface groups and developed porosity due to the presence of micropores. Regardless of the solid fraction, carbonization generates also gas and liquid fractions which are potential energy sources. īiochar is a fine-grained, porous, carbonaceous material produced in the process of biomass pyrolysis in an inert gas atmosphere. It confines the unrenewable sources overexploitation and eliminates the disadvantage of high costs of such materials as conventional active carbon, graphene or carbon nanotubes. Preparation and application of biochar is one of the effective methods of waste recycling. In addition, biochar plays an important role in improving soil fertility and increasing the carbon storage in the soil. Large surface area, low bulk density, great stability and strong adsorption capacity of biochar make it widely used in the sustainable environment and green technologies: monitoring of air pollution, wastewater treatment, biotechnology and renewable energy technologies as well as supercapacitors, catalysts and green nanocomposites. The interest in using biochar in environmental protection has increased significantly due to its physical and chemical properties. These results indicate the applicability of spruce cones as a cheap precursor for the sustainable production of the cost-effective and environmentally friendly biochar adsorbent. The maximum NH 3 adsorption capacity of the activated biochar was determined to be 5.18 mg g −1 (88.22 mmol g −1) at 0 ☌. The investigated activated materials have the specific surface areas from 112 to 1181 m 2 g −1.

All obtained activated biochars exhibit a largely microporous structure and an acidic character surface. It has been shown that spruce cones can be successfully used as a cheap precursor of well-developed surface biochars, characterized by a large pore volume and good sorption properties. The adsorption capacity and the possibility of ammonia desorption (TPD) were also examined. The surface properties of biochars were characterized by the nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM/EDS), X-ray fluorescence energy dispersion spectroscopy (ED-XRF), thermal analysis (TGA/DTA), infrared spectroscopy (ATR FT-IR), Raman spectroscopy and the Boehm’s titration method as well as the point of zero charge (pH pzc). The biochar product was obtained by means of the physical activation method. In this study the pyrolysis of Norway spruce cones, a lignocellulosic biomass was made.
