Sains Malaysiana 47(6)(2018): 1147–1155


Effect of Plasma Treatment (He/CH4) on the Glass Surface for the Reduction of Powder Flux Adhesion in the Spray Drying Process

(Kesan Rawatan Plasma (He/CH4) terhadap Permukaan Kaca untuk Pengurangan

Serbuk Lekatan Fluks di dalam Proses Penyemburan Pengeringan)





1School of Chemical Sciences and Food Technology, Faculty of Science and Technology

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia


2Plasma Technology Research Centre, Physics Department, Universiti Malaya

50603 Kuala Lumpur, Federal Territory, Malaysia


Diserahkan: 25 September 2017/Diterima: 5 Februari 2018




A 50Hz glow discharge He/CH4 plasma was generated and applied for the glass surface modification to reduce the powder adhesion on wall of spray dryer. The hydrophobicity of the samples determined by the water droplet contact angle and adhesion weight on glass, dependent on the CH4 flow rate and plasma exposure time. The presence of CH3 groups and higher surface roughness of the plasma treated glass were the factors for its hydrophobicity development. Response surface methodology (RSM) results using central composite rotatable design (CCRD) showed that optimal responses were obtained by the combination of parameters, CH4 gas flow rate = 3 sccm and exposure time = 10 min. In optimum conditions, the contact angle increased by 47% and the weight of the adhesion reduced by 38% (w/w). The plasma treatment could enhance the value of the contact angle and thus reduced the adhesion on the spray dryer glass surface.


Keywords: Flux adhesion; hydrophobic; plasma treatment; powder; spray dryer; surface treatment



Pelepasan cahaya 50Hz plasma CH4 dijana dan digunakan pada modifikasi permukaan kaca untuk mengurangkan lekatan serbuk pada dinding penyembur pengering. Hidrofobisiti sampel ditentukan oleh sudut sentuh titisan air dan pemberat lekatan pada kaca, bergantung kepada kadar pengaliran CH4 dan tempoh dedahan plasma. Kehadiran kumpulan CH3 dan kekasaran permukaan plasma yang lebih tinggi dengan rawatan kaca adalah faktor kepada pembentukan hidrofobisitinya. Keputusan kaedah gerak balas permukaan (RSM) menggunakan reka bentuk berputar komposit berpusat (CCRD) menunjukkan bahawa respons optimum diperoleh daripada kombinasi parameter, kadar pengaliran gas CH4 = 3 sccm dan tempoh dedahan = 10 minit. Dalam keadaan optimum, sudut sentuh meningkat sebanyak 47% dan pemberat lekatan dikurangkan sebanyak 38% (w/w). Rawatan plasma boleh meningkatkan nilai sudut sentuh dan seterusnya mengurangkan lekatan pada permukaan kaca penyembur pengering.


Kata kunci: Hidrofobik; lekatan fluks; penyembur pengering; rawatan permukaan; rawatan plasma


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