Abstract In this study, NaOH pretreatment, H2SO4 pretreatment, thermal pretreatment and production temperature were optimized to ensure maximum methane yield from hazelnut shells (HS) using the response surface methodology (RSM). A Box-Behnken design was achieved with four different independent variables and one dependent variable (methane yield). A total of 29 tests were performed after pretreatment according to the RSM design and to different production temperatures, suggesting optimum values for NaOH pretreatment, H2SO4 pretreatment, thermal pretreatment and production temperature were 3.5% w/v, 2.56% v/v, 145.66 °C and 34.65 °C, respectively. Under these conditions, the RSM-predicted methane yield was 215.896 mL/g volatile solid (VS). The high R2 value (0.9904) showed that the model could be applied effectively in the digestion of HS for the predicted methane yield according to the production temperature and pretreatments. In addition, lignocellulosic solubilisation was tested after pretreatment of the reactors according to the RSM operating conditions, which showed that the highest cellulose, hemicellulose and lignin solubilisation that could be achieved was 38.7% w/w (R10), 36.9% w/w (R22) and 50.5% w/w (R10), respectively. The modified Gompertz model supported the experimental cumulative methane yields (CMYs).

中文翻译：

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使用响应面法优化榛子壳甲烷产率的温度和预处理

摘要 在本研究中，采用响应面法 (RSM) 对 NaOH 预处理、H2SO4 预处理、热预处理和生产温度进行了优化，以确保榛子壳 (HS) 的最大甲烷产量。Box-Behnken 设计是通过四个不同的自变量和一个因变量（甲烷产量）实现的。根据RSM设计和不同生产温度，预处理后共进行了29次测试，表明NaOH预处理、H2SO4预处理、热预处理和生产温度的最佳值为3.5% w/v、2.56% v/v、145.66° C 和 34.65 °C，分别。在这些条件下，RSM 预测的甲烷产量为 215.896 mL/g 挥发性固体 (VS)。高 R2 值 (0. 9904) 表明该模型可以有效地应用于 H2S 消化，根据生产温度和预处理预测甲烷产量。此外，根据 RSM 操作条件对反应器进行预处理后，对木质纤维素的增溶进行了测试，结果表明，可以实现的最高纤维素、半纤维素和木质素增溶分别为 38.7% w/w (R10)、36.9% w/w ( R22) 和 50.5% w/w (R10)。修改后的 Gompertz 模型支持实验累积甲烷产量 (CMYs)。可实现的半纤维素和木质素增溶率分别为 38.7% w/w (R10)、36.9% w/w (R22) 和 50.5% w/w (R10)。修改后的 Gompertz 模型支持实验累积甲烷产量 (CMYs)。可实现的半纤维素和木质素增溶率分别为 38.7% w/w (R10)、36.9% w/w (R22) 和 50.5% w/w (R10)。修改后的 Gompertz 模型支持实验累积甲烷产量 (CMYs)。