title: Oil palm ash as partial replacement of cement for solidification/stabilization of nickel hydroxide sludge.
abstract: In this study, solidification/stabilization (S/S) of nickel hydroxide sludge using ordinary Portland cement (OPC) and oil palm ash (OPA) was carried out. The effects of increased substitution of OPA wt% in the S/S mix designs on the treated samples' physical and chemical characteristics were investigated. The physical characteristics studied were unconfined compressive strength (UCS) and changes in crystalline phases while chemical characteristics studied were leachability of nickel and leachate pH. Results indicated the optimum mix design for S/S of nickel hydroxide sludge using both OPC and OPA at B/S(d)=1 in terms of cost-effectiveness and treatment efficiency was 15 wt% OPA, 35 wt% OPC and 50 wt% sludge. The sufficient UCS and low leached nickel concentrations shown for this mix design indicate the viability of using OPA as substitute of OPC as it can significantly reduce cost normally incurred by usage of high amounts of OPC.
authors.affiliation: Faculty of Chemical Engineering, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia. yinyang@salam.uitm.edu.my
authors.forename: Chun Yang
authors.initials: CY
authors.lastname: Yin
authors.forename: Wan Shabuddin
authors.initials: WS
authors.lastname: Wan Ali
authors.forename: Ying Pei
authors.initials: YP
authors.lastname: Lim
mesh_terms: D002244:Carbon; D060729:Coal Ash; D003252:Construction Materials; D006863:Hydrogen-Ion Concentration; D006878:Hydroxides / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D000073878:Palm Oil; D052638:Particulate Matter; D010938:Plant Oils / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*; D018505:Waste Management / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D060729:Coal Ash; D006878:Hydroxides; D052638:Particulate Matter; D010938:Plant Oils; D012722:Sewage; C037473:nickel hydroxide; D000073878:Palm Oil; D002244:Carbon; D009532:Nickel