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The market for 1,3-propanediol (1,3-PDO) is growing rapidly due to its expanding uses in the polymer material industry. Catalytic hydrogenolysis of glycerol is a promising new way to produce 1,3-PDO sustainably. This paper reviews the recent advances in studies on heterogeneous catalysts for the selective hydrogenolysis of glycerol to 1,3-PDO. The main employed metal catalysts include platinum, copper, rhodium and iridium. With the intent to give a rationally guide to the development of new catalysts in future research, the catalysts performances are summarized and discussed with reaction mechanisms.

The hydrogenolysis of biomass-derived glycerol was studied on Ru-Co bimetallic catalysts, including Ru-Co/TiO2, Ru-Co/ZrO2, Ru-Co/SiO2 and Ru-Co/γ-Al2O3. The addition of Co to the Ru-based catalysts can promote the selectivity to 1,2-propanediol (1,2-PDO). The support material and Ru/Co atomic ratio has a significant effect on the catalytic performance. Ru-Co/ZrO2 exhibited the best performance as regard to both the activity and the selectivity to 1,2-PDO. Co is a promising second metal component to adjust the catalytic properties of Ru-based catalysts for the selective hydrogenolysis of glycerol.

A robust fault diagnosis and validation strategy for temperature sensors and ‘ow meters in central chilling plant is developed, which is based on the first law of thermodynamics. The strategy evaluates soft sensor faults (biases) by examining and minimizing the sum of the squares of concerned mass or steady state energy balance residuals represented by the corrected measurement over a period. It considers systematically all the concerned energy balances and obtains the best estimates of the sensor biases by minimizing the sum of the mean squares of normalized residuals of all energy balances involved. The genetic algorithm technique is employed to determine the global minimal solution to the multimodal objective function, which can be difficult to achieve by traditional gradient-directed search methods. Performance of an advanced robust fault detection, diagnosis and evaluation (FDD&E) scheme is compared with that of a sequential scheme, which was reported earlier, in simulation tests. The robust scheme is superior to the sequential scheme in robustness to abrupt sensor faults, such as biases, etc. The robust scheme is applied to a central chilling plant in an existing commercial building, providing satisfied bias estimates. As a basic method, the sensor FDD&E strategy is of practical value in heating, ventilation and air-conditioning (HVAC) systems as well as in systems where the measurements of liquid ‘ow variables are essential to control and performance monitoring.

The hydrogenation of biomass-derived ethyl lactate was studied over several ruthenium catalysts. The effect of support (TiO2, SiO2, γ-Al2O3, NaY and active-carbon) on the catalytic performance was evaluated. The ruthenium catalysts were characterized by inductively coupled plasma (ICP), N2 physisorption, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The catalytic performance of the ruthenium catalysts is dependent on the intrinsic property of the support. Ru/SiO2 was found to be an efficient catalyst for the hydrogenation of ethyl lactate to 1,2-propanediol (1,2-PDO).