Improvements in biohydrogen production from palm oil mill effluent (POME) has been achieved by optimizing the physicochemical conditions, using an enriched sludge as inoculum. Enrichment of biohydrogen-producing communities in the sludge was first carried out by heat treatment and acclimatization to POME. Response surface methodology (RSM) was then used for optimizing the operational parameters. The factors investigated were temperature, initial pH, and inoculum concentration. The output responses were evaluated based on the biohydrogen yield (Y_H2), biohydrogen production rate (R_H2), and COD removal efficiency. Microbial analysis of the enriched sludge at 100% POME concentration revealed the abundance of the Firmicutes phylum (98%) among the Bacteria population, with Clostridiaceae as the most abundant family. Archaea were inhibited at both 30% and 100% POME concentration. The optimum operational parameters generated by the RSM model were 34.7 °C, pH 5.81, and inoculum size of 14.22% (v/v), with the following predicted outcomes: Y_H2 of 42.29 mL H₂ gCOD⁻¹, R_H2 of 106.09 mL L⁻¹ h⁻¹, and COD removal efficiency of 23.66%. Meanwhile, the experimental data generated were as follows: Y_H2 of 41.18 mL H₂ gCOD⁻¹, R_H2 of 109 mL L⁻¹ h⁻¹, and COD removal efficiency of 25.96%. The process reliability was further demonstrated in a larger (2.5 L) continuously stirred-tank reactor, with the maximum biohydrogen yield obtained of 282 mL H₂ gCOD⁻¹ and COD removal efficiency of 35%. Butyric and acetic acids were the dominant soluble metabolites produced. These findings suggest that the RSM model generated was successfully used to optimize biohydrogen production from POME using enriched anaerobic digested sludge.

通过优化物理化学条件（使用富集的污泥作为接种物），已实现了棕榈油厂废液（POME）生物氢生产的改进。首先通过热处理和适应POME的方式来富集污泥中产生生物氢的群落。然后使用响应面方法（RSM）来优化操作参数。研究的因素是温度，初始pH和接种物浓度。根据生物氢产量（Y _H2），生物氢产生速率（R _H2）和COD去除效率评估输出响应。在100％POME浓度富集的污泥的微生物分析揭示的丰度厚壁菌门细菌种群中门类最多（98％），梭菌科是最丰富的科。在30％和100％的POME浓度下，古细菌都受到抑制。RSM模型生成的最佳操作参数为34.7°C，pH 5.81，接种量为14.22％（v / v），预测结果如下：Y _H2为42.29 mL H ₂ gCOD ^-1，R _H2为106.09 mL L ^-1  h ^-1，COD去除率为23.66％。同时，产生的实验数据如下：Y _H2为41.18 mL H ₂ gCOD ^-1，R _H2为109 mL L ^-1 h ^-1，COD去除率为25.96％。在更大的（2.5 L）连续搅拌釜反应器中进一步证明了工艺可靠性，获得的最大生物氢产量为282 mL H ₂ gCOD ^-1，COD去除效率为35％。丁酸和乙酸是主要的可溶性代谢产物。这些发现表明，使用富集的厌氧消化污泥，成功地将生成的RSM模型用于优化POME的生物氢生产。