Department of Biosciences & Bioengineering, Indian Institute of Technology, Guwahati, Assam, 781039, India.
Department of Biotechnology, Gandhi Institute of Technology and Management (GITAM) University, Visakhapatnam, Andhra Pradesh, 530045, India.
J Environ Manage. 2022 Jan 1;301:113927. doi: 10.1016/j.jenvman.2021.113927. Epub 2021 Oct 9.
The study demonstrates a two-stage integrated process for bio-methanol production using Methylosinus trichosporium NCIMB 11131, coupled with sequestration of methane and carbon dioxide. The first stage involved generation of methanotrophic biomass via sequestration of methane; which was used as biocatalyst to reduce carbon dioxide into methanol in the second stage. Maximum biomass titer of 3.39 g L and productivity of 0.60 g L d were achieved in semi-batch stirred tank reactor with methane concentration in the inlet gas mixture of 2.5% v/v and gas flow rate of 0.5 vvm. Methane fixation rate was estimated to be 0.32 g L d. Maximum methanol titer of 0.58 g L was achieved at headspace carbon dioxide concentration of 50% v/v and liquid to headspace volume ratio 10:90. Subsequently, a kinetic model was developed to predict and understand the system behaviour in terms of dynamic profile of growth, methanol formation, concentration of dissolved methane or carbon dioxide in the aqueous phase and headspace carbon dioxide concentration, in response to varying process parameters. The model can serve as a tool for estimation of process parameters and aid in overall production optimization.
该研究展示了一种使用甲基营养型甲烷杆菌 NCIMB 11131 进行生物甲醇生产的两阶段集成工艺，同时实现了甲烷和二氧化碳的捕集。第一阶段涉及通过捕集甲烷来生成甲烷营养型生物量；然后将其用作生物催化剂，在第二阶段将二氧化碳还原为甲醇。在入口气体混合物中甲烷浓度为 2.5% v/v、气体流速为 0.5 vvm 的半分批搅拌釜式反应器中，实现了最大生物量浓度 3.39 g/L 和 0.60 g/L d 的生产力。甲烷固定速率估计为 0.32 g/L d。在顶空二氧化碳浓度为 50% v/v 和液-气比为 10:90 的条件下，达到了最大甲醇浓度 0.58 g/L。随后，开发了一个动力学模型，以根据生长、甲醇形成、水相和顶空二氧化碳中溶解甲烷或二氧化碳的浓度的动态曲线，来预测和理解系统行为，以响应不同的工艺参数。该模型可作为估计工艺参数和辅助整体生产优化的工具。
