UNDERSTANDING THE EFFECT OF BALL MILLING PRETREATMENT ON THE SURFACE FUNCTIONALITY OF BIOCHAR CATALYSTS - MAPS

Macroporous and mesoporous materials such as biochar (BCR) has proven favorable as the relatively larger pores can improve molecular diffusion for the large molecules and their surface functional groups are easily tuned for interaction with various substrates. Our previous INS study of raw BCR show that the material has a slightly higher population of aromatic components than aliphatic compounds. The CH–OH ratio in the raw BCR is ~5, showing that the hydroxyl functional groups are a minority species. C–H stretch modes are the majority species with a ratio of sp3–CH:sp2–CH of 1:1.3. We now wish to understand the effect of pretreatment of BCR on their surface functionality, in particular via the ball milling pretreatment technique as it is considered a promising cost effective alternative method of producing materials with greater surface characteristics. Two types of BCR from different feedstock will be used - palm oil empty fruit bunch and coconut shell waste. Samples pretreated using conventional acid pretreatment will also be carried out. The comparison of BCR from different feedstock and pretreatment techniques will aid the understanding of the correlation between the targeted pretreatment conditions and structure characteristics of BCR before use for catalytic purposes.

大孔介孔材料（如生物炭（biochar, BCR））已被证实具备优异应用性能：其相对较大的孔径可改善大分子的分子扩散行为，且表面官能团易于调控，可与多种底物发生相互作用。我们此前针对原始BCR开展的非弹性中子散射（Inelastic Neutron Scattering, INS）研究显示，该材料的芳香族组分占比略高于脂肪族化合物。原始BCR的碳氢/羟基（CH–OH）比值约为5，表明羟基官能团为少数组分。碳氢键伸缩振动模式为主要组分，其中sp³杂化碳氢（sp³–CH）与sp²杂化碳氢（sp²–CH）的占比为1:1.3。本研究旨在探究BCR预处理对其表面官能团的影响，重点关注球磨预处理工艺——该工艺被视为一种极具前景的低成本备选方案，可制备出具备更优表面特性的材料。本次实验将采用两种不同生物质原料制备的BCR，分别为棕榈油空果串与椰子壳废弃物，同时还将制备经传统酸预处理的样品。通过对比不同原料与不同预处理工艺制备的BCR，将有助于厘清目标预处理条件与BCR结构特性之间的关联，为后续催化应用奠定理论基础。