This study investigates the application of supercritical CO (SC-CO) in acerola waste pretreatment for hydrothermal carbonization, examining the impact of ZnCl as an additive. Quantified response variables included hydrochar yield, high heat value, energy yield and oxygenated functional groups. Four equations were proposed to correlate the independent variables-additive concentration (C), temperature (T) and residence time (t)-with each response. Subsequently, a multiple-response optimization study was conducted to determine the best conditions, considering all responses. Utilizing SC-CO pretreatment and ZnCl additive resulted in hydrochar with the highest values for all responses. The optimum conditions obtained were T = 161.4°C, t = 105.5 min, and C = 1.43%. The hydrochar obtained under optimal conditions demonstrated that the supercritical CO pretreatment associated to the use of ZnCl additive increased the process yield in 11.02% and the energy yield in 13.02%, confirming the potential application of the hydrochar as a solid fuel.

中文翻译：

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以超临界 CO2 和氯化锌为添加剂预处理的针叶樱桃 (Malphigia Emarginata. DC) 废物的水热碳化

本研究探讨了超临界 CO (SC-CO) 在针叶樱桃废物预处理水热碳化中的应用，并考察了 ZnCl 作为添加剂的影响。量化的响应变量包括水热炭产量、高热值、能量产量和含氧官能团。提出了四个方程来将自变量——添加剂浓度（C）、温度（T）和停留时间（t）——与每个响应相关联。随后，进行了多重响应优化研究，以确定最佳条件，考虑所有响应。利用 SC-CO 预处理和 ZnCl 添加剂产生的水炭在所有响应中均具有最高值。获得的最佳条件为T = 161.4°C，t = 105.5 min，C = 1.43%。在最佳条件下获得的水热炭表明，与使用 ZnCl 添加剂相关的超临界 CO 预处理将工艺产率提高了 11.02%，能量产率提高了 13.02%，证实了水热炭作为固体燃料的潜在应用。