Solar pyrolysis of cotton stalk in molten salt for bio-fuel production

Abstract

Solar pyrolysis of cotton stalk was carried out in a molten salt reactor heated by 4 kW solar simulator. The effects of pyrolysis temperature and mass ratio of molten salt to biomass on pyrolysis products properties were investigated. The use of molten salt as pyrolysis media increased gas yield. At 850 C, the gas yield (mainly of CO and H 2) continued to rise from 41.35 wt% to 82.57 wt% when mass ratio of molten salt to cotton stalk increased from 0 to 10. Pyrolysis in molten salt significantly decreased bio-oil acids and phenols, while increased aromatics among pyrolysis temperature range of 450e850 C. There was positive correlation between the increased content of aromatics and mass ratio of molten salt to cotton stalk (from 0.5 to 10). The bio-char carbon content showed a general decreasing trend while oxygen, BET surface area and pore volume increased with using molten salt as pyrolysis media. Bio-char obtained from CS1MS5 pyrolysis at 850 C had the highest BET surface area of 972.57 m 2 /g and the biggest total pore volume of 0.6203 cm 3 /g. High quality pyrolysis products with more uniform chemistry suggest catalytic reactions occur inside the solar reactor due to the intermediates degradation with molten salt.

Molten salt pyrolysis of biomass: The evaluation of molten salt

“…It should be noted that the biomass could be well immersed and dispersed in the molten salt in our device when the ratio of molten salt to biomass reached 5, which can make full use of the catalytic performance of molten salt. Moreover, under the condition of ensuring that all salts can be fully melted, the pyrolysis temperature of 850 • C is selected based on our previous work to obtain higher quality pyrolysis products [14].…”

“…Thus, the selectivity of molten salt to biomass pyrolysis products is the decisive factor to evaluate molten salts. The upgrading effect on different pyrolysis products of ternary carbonate have been widely reported [13][14][15]. Adinberg et al [4] observed the enhancement of the selectivity regarding the gas product with the molten Na 2 CO 3 -K 2 CO 3 during the fast pyrolysis of cellulose particles.…”

Silver microsphere doping porous-carbon inspired shape-stable phase change material with excellent thermal properties: preparation, optimization, and mechanism

“…Figure 4 depicts the FT-IR spectroscopy curves of SMS-CSP, 70% PEG/SMS-CSP, and PEG. The peak at 1618 cm −1 was attributed to the stretching vibration of –OH 24 . The absorption peak at 3415 cm −1 was attributed to the stretching vibration peak of –OH 19 .…”

Investigation of element migration characteristics and product properties during biomass pyrolysis: a case study of pine cones rich in nitrogen

“…37 The effect of pyrolysis temperature on PC mass yield was similar to the effect on other biomass (e.g., cotton stalk, eucalyptus, and rice husk). [38][39][40] 3.2.2 Biochar 3.2.2.1 Physicochemical properties of biochar. Physicochemical properties for biochar are listed in Table 1.…”