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Since the discovery of graphene, chemical vapor deposition (CVD) is by far the best method to produce the material. However, optimization of the process’ parameters is not yet completed. One of the most debatable issues in CVD is the effects of hydrogen towards graphene. In this research, the quality of graphene on copper and palladium substrates as a function of various hydrogen concentrations during annealing as well as different annealing times is studied. Copper and palladium substrates are chosen due to their difference in carbon/hydrogen diffusivity and solubility. Raman analysis showed that upon annealing under higher hydrogen concentration, the graphene grown is defective and with multiple layers. On the other hand, prolonged annealing time is detrimental to the quality of both substrates. Empirical-based calculations showed that both substrates experienced an increase in graphene layers as both H2 concentration and annealing time were increased. We postulate that the presence of defects and multilayer graphene are caused by the hydrogen trapping phenomenon inside the substrates’ vacancies and also the activation of potential defects’ sites through hydrogen adsorption. Graphical representations of the relationship between hydrogen concentration and annealing time towards graphene quality were plotted to suggest the optimized parameters in producing pristine graphene.

Iron and steel industries are major contributors to global CO2 emissions. Biomass has been proposed as an alternative cleaner and renewable fuel to reduce emissions from these industries. During iron sintering a large amount of greenhouse gases is emitted; therefore, it is desirable to substitute fossil fuels with biomass. In this study, coke was substituted with charcoal derived from oil palm empty fruit bunch (EFB) as an alternative fuel for sintering of iron ore. The EFB was heated at 450 °C for 30 min to produce charcoal, and the mixture of iron ore mixed and charcoal was sintered by heating at various temperatures from 950 to 1150 °C in the presence of 1% limestone. The sintered particles coalesced to a larger extent at higher temperatures and the porosity significantly decreased. The average sinter particle density was found highest at 1150 °C. Sintering caused the porosity to decrease by ∼50.42% between the highest (1150 °C) and lowest (950 °C) temperature. With increasing heating temperature, the compressive strength of the sinter significantly increased. The morphology suggested that melt formation facilitates the coalescence of small pores and irregularly shaped pores into more rounded shapes pores, thus reducing the number of larger pores. Meanwhile, the addition of charcoal content has a detrimental effect on the properties of sinter. By increasing the charcoal content attributed to the decrement of apparent density and compressive strength of the sinter. The use of charcoal from EFB as an energy source for sintering Malaysian iron ore can potentially reduce CO2 emissions in iron-making processes approximately 183.3 kg per ton.

Demand for forestland for non-forest uses, mostly oil palm, has increased dramatically in the past few years and has become a chief driver of deforestation in Central Kalimantan. In this paper, we aim to shed light on how multiple levels of government create a facilitating environment for oil palm expansion. In our research, we employed three different methods: content analysis of key policy documents, participant observations, and expert interviews. We found that the technical complexities of formal procedures for the conversion of forest to oil palm are relatively easy to bypass. Contradicting laws and regulations have created a situation where the Ministry of Environment and Forestry (MoEF) and local governments have relatively equal legal mandates and authority over land-use and allocation. This is further complicated by the ambiguity of the decentralization policy. Enabled by the spatial planning law and the decentralization laws, local governments have aggressively issued plantation licenses for forest areas without the formal release of the forest from the Ministry of Forestry. The issuance of plantation permits has also been legitimized by other policies within central government, which have made oil palm a national priority.

There has been an increasing occurrence of spontaneous and organized movements and struggles demanding access to state forestland in Indonesia over the past few years. A sizeable body of literature has explained the driving factors of the land movement but most of them focus on processes at the national level, principally on the changing socio-political landscapes, and the overlapping land use policy and regulations. In contrast, this paper attempts to find explanation of the dynamics of the land movement, and tries to explain the emerging power of peasant farmers at the field. The research was conducted in the forest of the state company of Perhutani Sub-Forest District (BKPH) Kalibodri, Forest District (KPH) Kendal, Central Java, where nearly two-fifths of the forestland is illegally occupied by peasant farmers for agricultural cropping. This paper borrows actor-centred power (ACP) of Krott et al. (2014), which offers an analytical approach to understand the empirical power resources of actors in social-political relationships. It finds the prolonged occupation of the state forestland is due to the combination of the weakened power of the state apparatus and the more consolidated power of peasant farmers. The state apparatus is weakened by its diminishing coercive power. It is also unable to provide concrete incentives that would otherwise alter the behavior of the peasant farmers. At the same time, the peasant farmers accumulate support from a wider society, from local to national level. Even international actors also play a part so that significantly affect how the state company deals with the peasant farmers.

The Indonesian timber legality verification system was launched ten years ago with the objective of eradicating illegal logging and improving domestic forest governance. At the heart of the legality system, independent monitoring (IM) was designed as an innovation to ensure its credibility and legitimacy. This paper analyzes the challenges facing IM networks in the Indonesian timber legality assurance system and examines what lessons can be learned to further develop ideas and strategies that strengthen the effectiveness of their activities. The current experience in Indonesia suggests that IM still faces some major structural challenges to fulfill high expectations. Above all, the existence and roles of IM bodies within the legality system are not yet fully understood and are often questioned by other stakeholders. There has been some degree of skepticism about their impartiality. IM is also constrained by the limited personnel available to manage it. This situation is not aided by the complex administrative requirements to become involved in IM activities. Access to data and information is another challenge that may hinder the role IM can play in fostering good forest governance. Furthermore, IM relies heavily on donor funding to finance their project-based activities. IM bodies need to explore models and schemes for more sustainable funding for their activities.

Smallholder tree plantation, now on the increase in Indonesia, has long been practiced by rural farmers as a strategy to optimize the expected utility of land, labor and other constraints. Increasing demand for timber has driven a shift toward commercialization of smallholder forestry. However, smallholders face huge challenges when they seek for commercial markets in the form of complex regulatory frameworks applied to smallholder plantations. This paper discusses the case of smallholder plantations in Gunungkidul District (Indonesia), considered one of the most commercialized timber marketing hubs for local, national and international markets. It analyzes how opportunities and challenges, resulted from different regulatory frameworks, affect the competitiveness of smallholder forestry practices. In this paper, regulatory frameworks are defined as not only regulations issued by public administrators at the domestic (local and national) level, but also cover the emerging market-based regulatory frameworks, i.e. voluntary certification of sustainable forestry and mandatory timber legality verification.

Effective use of local iron ore and biomass waste as energy and material resources in iron making is an interesting economic prospect since Malaysia imports iron ore to supply its domestic steel consumption while there is an abundance of biomass waste from the palm oil industry. In this work, a composite pellet made of Malaysian iron ore with palm kernel shell (PKS) waste was subjected to reduction tests using an electric tube furnace to investigate the effect of temperature and PKS content on reduction rate. Several iron ore samples taken from different mining locations were subjected to thermal and X-ray diffraction (XRD) analysis. The rate of iron ore reduction increased with increasing temperature up to 900 °C. XRD analysis revealed that the original iron ore mainly contains iron oxide hydrate and was converted into simple hematite after heating and then become magnetite after reduction. The Fe content in the original ore increased almost 12% when 40 wt% of PKS was used. The iron oxide was successfully reduced to magnetite and small amount of wustite when up to 20 wt% of PKS was present in the mixture. Besides, 20 wt% of PKS in reduction process can reduce CO2 emissions by almost 18.69 wt% as well as decrease carbon consumption by 19.78 wt%. Thus, the utilization of biomass as a reducing agent for low grade iron ore reduction is an attractive method for upgrading iron ore as well as reducing CO2 emissions.

Possibility of hydrogen production from biogas using hot slag has been studied, in which decomposition rate of CO 2 – CH 4 in a packed bed of granulated slag was measured at constant flow-rate and pressure. The molten slag, discharged at high temperature over 1700 K from smelting industries such as steelmaking or municipal waste incineration. It has enough potential for replacing energy required for hydrogen production due to the catalytic steam reforming or carbon decomposition of hydrocarbon. However, heat recovery of hot slag has never been established. Therefore, the objective of this work is to generate hydrogen from methane using heated slag particles as catalyst, in which the effect of temperature on the hydrogen generation was mainly investigated at range from 973 to 1273 K. In the experiments a mixed gas of CH 4 and CO 2 was continuously introduced into the packed bed of hot slag at constant flow-rate and atmospheric pressure and then the outlet gas was monitored by gas chromatography. The results indicate that slag acted as not only thermal media but also good catalyst, for promoting decomposition. The product gases were mainly hydrogen and carbon monoxide with/without solid carbon deposition on the surface of slag, depending on the reaction temperature. Increasing temperature led to large hydrogen generation with decreasing un-reacted methane in the outlet gas, at when the largest methane conversion was about 96%. The results suggested a new energy-saving process of hydrogen production, in which the waste heat from molten slag can replace the energy required for hydrogen production, reducing carbon dioxide emission.