Effect of pyrolysis temperature on the biochar nutrient and water retention capacity

Empty fruit bunch (EFB) is a convenient source of biomass in Malaysia that might be transformed into biochar for soil fertility. EFB were pyrolized in rotary drum chamber at 3 different temperatures, such as 300, 350 and 400°C for 3 hours with a heating rate of 3°C/min and 0.5 rotations per minute (RPM) to know the effect of pyrolysis temperature on the quality of biochar. Yield of EFB biochars were 21.5, 19.5 and 18.0 wt% in case of 300, 350 and 400°C pyrolysis temperature, respectively. Water retention was found more in biochar that produced from 400°C in each cases of 100g sandy soil + 100 ml water + 1g biochar, 50g sandy soil + 50 ml water + 0.5g biochar, 25g sandy soil + 25 ml water + 0.25g biochar. Phosphorus (P) concentration was more or less similar in all biochars, but there was a clear variation found in case of potassium (K) content at different temperatures of biochar produced. The K content was 0.604, 0.840, 1.080 and 1.220 ppm in case of without biochar, biochar of 300, 350 and 400°C respectively, after 15 days of biochar & fertilizer addition to the soil. It might be stated from the study that biochar produced from 400°C showed the higher ability to water and nutrient retention.