Through orthogonal test and single factor experiment, biochar (BC) was ready by exploitation cyanobacterial sludge and bagasse to explore the potential of changing completely different energy at different carbonization temperatures and the result of Cr(VI) removal by BC. Biochar was prepared from dried cyanobacterial sludge and bagasse under 500 °C, 400 °C and 300 °C at 3.0 h, 2.5 h and 2.0 h under high temperature limited oxygen, respectively. Orthogonal experiments were used to conduct L9(34) three-factor and three-level experiments. Combined with single factor experiments, the optimal combination conditions for Cr(VI) removal were explored. Solid-state energy mainly was in the form of biochar yield. Higher temperature and content of biochar from bagasse had lower solid-state energy by biochar yield (44.00%±0.35%). Cyanobacterial sludge has wide application prospect and nice potential and application prospect in energy conversion. The dismissal of Cr(VI) with biochar was the primary to extend, and so decrease with the rise of charring temperature. The highest expulsion of Cr(VI) was attained once the mass quantitative relation of mixed biochar was 3:1. With a charring time of 2.5 hours, a charring temperature of 400 °C, and a biochar mass quantitative relation of 3:1, up to 98% of Cr(VI) was removed most effectively. Medium temperature biochar and biochar prepared from the mixture of cyanobacteria sludge and bagasse are beneficial to the production of solid energy. Cyanobacterial sludge-based biochar has broad application prospects, especially in energy conversion. In the orthogonal experiment, the sequence of influences of various factors on Cr(VI) removal rate was as follows: carbonation temperature > carbonation time > biochar ratio. The following were the ideal conditions for removing Cr(VI) from biochar: acieration temperature (400 °C), acieration time (2.5 hours), and biochar mass-quantity ratio of 3:1.
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