Characteristics of three biochar types with different pyrolysis time as ameliorant of peat soil

Abstract

Biochar is a pyrolysis product resulted from biomass burning in oxygen limited conditions and is expected to serve as soil ameliorant.In this paper a laboratory study was conducted using three types of biochar ( palm empty fruit bunches (tankos), rice husk and peat from Bengkalis). The study was aimed at identifying the characteristics of each biochar burned at a temperature of 350 °C with different pyrolysis time (3, 4 and5 hours). The analysis of lignin content showed that the peat from Bengkalis has higher lignin (50.23%) followed by tankos (41.96%) and rice husk (18.40%). The results of Fourier Transform Infrared Spectrometer (FTIR) show lower-layer Bengkalis peat (A2) has more functional group than husk burned for three hours and four hours (8 types and 12 types). The appearance of rice husk biochar surface pores pyrolyzed for 3 hours, with 1000x magnification is sturdy and orderly arranged, smaller macro and micro pore size (3.758μm) than of husk biochar pyrolyzed for four hours (1.612 μm; 1.800 μm; 2.593 μm). In Bengkalis peat (A2), the macro and micro pores are sturdy and orderly arranged, the size of the pores is partially collapsed so that it is smaller and cannot be measured. Large and orderly arranged structure and form of pores will increase the role of biochar as ameliorant in the soil. The formation of intact pore makes biochar better in terms of bulk density, particle density, and aeration.