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Cu/ZnO/Al2O3 catalyst with the addition of tri-promoters (Mn/Nb/Zr) was investigated with respect to their catalytic activity and stability in a prolonged reaction duration in methanol synthesis. Spent catalysts were characterized using N2 adsorption-desorption, FESEM/EDX, TEM, N2O chemisorption, and XPS for their physicochemical properties. The catalyst longevity study was evaluated at two days, seven days, and 14 days at 300 °C, 31.25 bar, 2160 mL/g.hr GHSV, and H2:CO2 at 10:1. The CO2 conversion and methanol yield decreased by about 5.7% and 7.7%, respectively, when the reaction duration was prolonged to 14 days. A slight reduction in catalytic activity under prolonged reaction duration was found due to thermal degradation.

Precipitated calcium carbonate (PCC) is synthetic calcium carbonate that has high purity of more than 98 wt% of CaCO3 content.  Owing to its unique characteristic whereby its shape and size can be controlled to tailor to various applications, PCC has seen great demands in many industries such as paper, paint, plastic, food, ceramics, cosmetics, pharmaceutical, and many others.  PCC can be synthesized via various methods and the most often used method in industry is via carbonation process.  This process has caught interest of the oil and gas industry for utilizing existing carbon dioxide waste from plant processes.  Precipitation of PCC is carried out using hydrated lime under various conditions at different gas purity (1 mol% CH4 + 99 mol% CO2 , 40 mol% CH4  + 60 mol% CO2 ), different gas flowrate, and different stirring rate.  All experiments are carried out using 1 litre of ionic solution at ambient conditions.  All samples are characterized using Field Emission Scanning Electron Microscopy (FESEM), Particle Size Distribution, X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF).  FESEM analysis shows different surface morphology for different methane content with calcite formation.  The particle size for all PCC produced at different parameters are comparable at the range 5-9 microns depending on the mixing rate used whereas XRF results indicate very high purity of CaCO3 of more than 99 wt%.

Development of ultra high CO2 field in Malaysia is the next frontier as far as contaminated green field development is concerned. Large hydrocarbon reserve is a major driver to mature technology to support the development of contaminated fields. However, managing the contaminant CO2 is still a major drawback as far as technology is concerned. Base case consideration for CO2 emission mitigation for offshore high CO2 gas fields had always been geological injection even though it deteriorates the overall field economics to a point which may prove to be prohibitive for some field development cases. An alternative method to mitigate CO2 would be the conversion of CO2 to higher value products which provides return in the form of additional revenue or profit. The monetory income from the conversion of CO2 can be utilized to either fully or partly offset the high cost of CO2 injection. This paper attempts to summarise the experience based on feasibility study, technical consideration and lesson learnt by PETRONAS to mitigate the CO2 emissions from the development of such high CO2 gas fields. The summary is done in the context of selecting the suitable CO2 mitigation technology, scale of conversion, maturing the technology and economic consideration as an integral part of the field development.

Carbon dioxide (CO2) management is vital for ensuring the economic and environment viability for monetization of high CO2 gas field. Apart from the great technical challenge in separating high concentration of CO2 in gas field economically, the management of separated CO2 is a fine balance between the sink-in value by sequestration and creation of value via conversion to product, constrained by the thermodynamic challenge in breaking the stable CO2 molecule. Conversion to methane is one the exploratory idea due to ease of integration to current product line-up of PETRONAS. Catalytic conversion of CO2 to methane are reported here over various supported nickel base catalyst, namely ZrO2, La2O3, and Al2O3 at temperature ranging from 300 to 400°C under atmospheric pressure. The catalysts with fixed Ni loadings were prepared by wet impregnation technique, characterized and their performances were evaluated in a parallel reactor under Sabatier-based CO2 conversion. Reaction temperature and GHSV were taken into account as two important parameters with fixed H2/CO2 molar ratio. Experimental results indicate that among all catalysts, Ni/Al2O3 give the highest CO2 conversion of 74% and high CH4 selectivity of 99% at temperature of 380°C and GHSV 10000 h-1. This asserted Ni supported on Al2O3 as a potential catalyst for CO2 conversion and promising methanation performance over a low cost catalyst.

Exploration and production of sour gas field raise the need for CO2 management to minimize the adverse effect of green house gas venting to the environment. It is a fine balance between the sunken value of CO2 reinjection and value creation in CO2 conversion to value product, essential in ensuring project’s economic viability. Conversion to methane is selected due to the ease of integration with current process facility. Catalytic conversion of CO2 to methane are reported here over metal oxides (Al2O3, ZrO2 and La2O3) supported Nickel base catalysts over a range of temperature and GHSV with fixed H2/CO2 molar ratio. The catalysts were prepared by wet impregnation technique at room temperature. It was then characterized with X-Ray Diffraction (XRD), Brunauer–Emmett–Teller (BET), Temperature Programmed Reduction (TPR) and Temperature Programmed Desorption (TPD). All catalyst systems showed trend of decreasing CO2 conversion when the GHSV is increased from 10000 to 15000 h-1, which is in line with short reactant contact time. The impact is more pronounced at low temperature of 300 °C, but at high temperature of 400 °C, the conversion is almost comparable irrespective of GHSV. Experimental results indicate that Ni/Al2O3 gives the highest CO2 conversion of 74% while 7% and 67% for Ni/ZrO2 and Ni/La2O3 respectively. There is a prospect for further scaling up to complement the current commercial catalyst proven for handling low concentration of CO2.

CO2 utilization into minerals is one of the most efficient methodologies although much research concerns the utilization of CO2 to produce chemicals. The production of precipitated calcium carbonate (PCC) from three different starting materials has been reported. The gas-liquid reaction is carried out by bubbling carbon dioxide into a solution of lime products with fixed parameters of 99% CO2 purity, 4.0 L/min of flow rate and 1500 rpm stirring rate at atmospheric pressure. The PCC was then characterized for X-Ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-Ray fluorescence (XRF) and particle size. Experimental results indicate that the PCC produced from quick lime showed the highest yield of 17.27 g, however there is no significant difference for both carbide lime and hydrated lime at 12.04 g and 11.57 g respectively. Morphology, phase structure and particle size of PCC produced reveals insignificant influence with different starting materials. Producing PCC from CO2 and natural minerals can be a potential method of reducing CO2 emissions by locking-up CO2 in a stable mineral form, whilst at the same time turning low quality natural minerals into high valuable products.

Permanent abatement of CO2 has become a major challenge in many gas field developments especially within this South –East Asia region. Among the challenges are on how to dispose or utilize this huge amount anthropogenic CO2 safely and economically. Therefore, the objective of this study is to identify the best technology for non-catalytic CO2 Direct utilization to manage and support economic development of high CO2 gas field in Malaysia. A Market survey was conducted to a few shortlisted technologies to assess on the technology landscape and the market potential. The feedback was analyzed based on the criteria established on the basis of company requirement. From the study, ‘Mineral Carbonation’ has been identified as one of the potential technology solution for permanent sequestration of CO2 in Malaysia. The future of this technology application is very promising due to the availability of the local feedstock, mineral waste and the potential market of this product especially for carbonate product such as precipitated calcium carbonate (PCC). However, this technology still possesses some technical challenges due to slow kinetic reaction. For a large scale application, this will become more demanding especially in terms of footprint as the current technology is mainly on batch process. Therefore, the current R&D should look into area where this process kinetic can be improved and to look into continuous or semi-continuous process for smaller footprint.