CAS竹炭是以台灣產3年生以上且未經防腐劑、防蟻劑、膠合劑、塗料或其他藥劑處理過的成熟竹為材料,以炭化窯(土窯、磚窯等)、機械爐等設備,經高溫炭化技術,精心煉製而成。
CAS木炭則是以木材炭化所得之炭化物,原料材之種類如闊葉樹、針葉樹、混合材及木屑成型物等,且不得經防腐劑、防蟻劑、膠合劑、塗料或其他藥劑處理過者。在木炭前面冠以樹種名稱,如相思樹炭、龍眼炭等以區別其原料種類。以混合材為原料者稱之為混合材炭,以木屑成型物為原料者稱之為木屑炭。
另將炭化窯排煙口所排出的煙,經過冷卻後所得之液體,再靜置6個月後,去除上層部分的輕質油及下層部分的沉澱焦油,所得中層部分的液體為竹醋液或木醋液,或經蒸餾成蒸餾竹醋液或蒸餾木醋液。

● CAS竹炭、竹醋液、木炭及木醋液之特色

★影響竹炭及木炭品質的因素很多,因此CAS竹炭及木炭評核時,會針對作業區環境及硬體、原料、製程、品質、衛生、倉儲管理等項目,進行嚴格的審核,並要求業者必須在包裝上標示清楚,如依用途別標示精煉度、元素分析碳含量、比表面積、硬度、含水率(僅適用木炭)及熱值(僅適用木炭),並詳述原料木竹產地及種類、製造方式、形狀、淨重、使用說明及注意事項、製造日期、製造者等相關資料。

★竹醋液及木醋液在收集過程中,亦會因炭化溫度不同,造成成份的變化。
因此CAS竹醋液及木醋液特別規定,收集範圍應為炭化窯排煙口溫度80℃~140℃或機械爐爐內溫度200℃~350℃所排出的煙,並依製造方法的不同,分為竹醋液及蒸餾竹醋液、木醋液及蒸餾木醋液。其具有獨特煙燻香氣之酸性液體,比重約為1.002~1.02,pH值則約為2~3.7左右,其中水佔大部分,約有90%以上,其他則是以醋酸為主之複雜天然有機成分。

● 如何選購CAS竹炭、竹醋液、木炭及木醋液

1. 選擇具有CAS標章之產品。
2. 竹炭及木炭
(1)外觀:平整且表面無焦油層。
(2)炭化程度:整體炭化完全。
(3)氣味:無其他異味。
(4)無污染物、霉斑或其他異物附著。
(5)包裝須堅固完整,不可使內容物外漏或變質。
(6)標示清楚完整者。
3. 竹醋液及木醋液
(1)透明或無色/淡黃色/淡紅褐色/紅褐色。
(2)無懸浮物,不得有焦油微粒子或其他雜質、異物。
(3)具備竹醋液及木醋液之特殊氣味。
(4)本品之容器應使用耐酸性材質。
(5)所使用包裝應密閉完好、外觀良好潔淨、無銹蝕、無溢出或其他變形。
(6)標示清楚完整者。

● CAS竹炭、竹醋液、木炭及木醋液之用途

1. 竹炭的炭質結構孔隙多,因此具有很強的吸附能力及調節溼度和消除臭味等功能。另外竹炭還能釋放適合人體吸收的遠紅外線,而達到保溫蓄熱、促進血液循環。目前已應用於開發系列新興民生用品,如洗劑類、煮飯類、活性碳類及竹炭紗類等。
2. 木炭亦具吸附能力及調節溼度和消除臭味等功能。但因木炭所具之孔洞數量及大小與竹炭有所差異,故吸附及調濕效能較竹炭低。木炭亦能釋放適合人體吸收的遠紅外線,而達到保溫蓄熱、促進血液循環的功能。完全炭化之木炭,當燃料使用時較不易產生煙。
3. 竹醋液及木醋液可以除臭、防腐和抑菌。

‧CAS林產品-英文

CAS certified bamboo charcoal and bamboo vinegar CAS certified bamboo charcoal is made from mature bamboo over four years old, which is free from preservative, termite-proof chemical, glue, coating or other biochemical treatment. The well selected bamboo is subject to high temperature carbonization by conventional kiln or mechanical furnace with controlled procedure. The smog with temperature at 80℃-140℃collected from smoke discharge outlet during carbonization is cooled down and condensed into liquid which is left to sit for six months, during which the liquid separates into three layers. The upper layer of light-weighted oils and the lower layer of bamboo tar are discarded and the remaining middle layer of bamboo vinegar is distilled and then tested for safety and the qualified product can be entitled as CAS certified bamboo vinegar . 
Requirements for CAS certified bamboo charcoal and bamboo vinegar 

Since many factors may affect the quality of bamboo charcoal, therefore an array of check-up items will be thoroughly inspected and appraised during document review and on-site evaluation for the applicants of the CAS certification. Theses check-up items include environment of operation area, facility and hardware, raw materials, manufacturing process, quality, environmental hygiene and warehouse management. In addition, the labeling must carry important information such as index of refinement (electrical resistivity), fixed carbon content, BET value(specific surface area),hardness, species and origin of bamboo, manufacturing method, shape, net weight, user instruction and important notice, production date, manufacturer or vendor. 
As the variation in carbonization temperature could result in change in the composition of the bamboo vinegar produced , the CAS regulation specifies that only the smog with temperature at 80℃-140℃ collected from smoke discharge outlet of carbonization furnace cab be used to yield bamboo vinegar. Depending on the manufacturing method, the bamboo vinegar can be classified as preliminary or distilled bamboo vinegar. 

How to select good bamboo charcoal and bamboo vinegar? 

(1) How to select good bamboo charcoal? 

Good bamboo charcoal has undmaged and undeformed surfaces.Bamboo charcoal that has undergone high-temperature refinement has smooth surfaces, is structurally dense, makes sharp metallic sounds when knocked and has high electrical conductivity. 
Different application requires different types of bamboo charcoal.Bamboo charcoal made at low temperatures (from 450–600°C) is suitable for agricultural applications, for example, as soil improvers or fertilizers. Bamboo charcoal made at medium temperatures (600–800°C) is appropriate for applications such as deodorizing and dehumidifying. Bamboo charcoal made at hig temperatures (from 800–1000°C) is suitable for health-related applications,such as far-infrared radiation emission and electromagnetic radiation shields. 

(2) How to select good bamboo vinegar? 

When bamboo undergoes high-temperature carbonization, many complicated chemical reactions (such as heat decomposition and re-combination reactions) occur, forming many structurally complex compounds. One such compound is tar, which is a carcinogen. Hence, the liquid must be refined to eradicate the tar. Other types of bamboo vinegar commercially available from the market are those that have not undergone such refinement. Refined bamboo vinegar has a slightly yellowish color and contains no suspended particles. 

(3) The above criteria for picking out good bamboo 
charcoal and bamboo vinegar are very simple. The best way to be sure of product quality is to purchase CAS(Certified Agricultural Standards) (i.e., certified by the Forestry Bureau of the Council of Agriculture) bamboo charcoal and bamboo vinegar, since the Forest Bureau of the Council of Agriculture conducts strict checks on the manufacturing process including the factory environment, the equipment used, raw material used, manufacturing processes adopted, quality, health related issues and storage matters. Additionally, the Bureau requires a CAS-certified product to carry relevant information including the grade, suggested applications, type and origin of bamboo, manufacturing process, usage directions, specific matters to be aware of and details of the manufacturer and seller on the product packaging. 

Applications of good bamboo charcoal and bamboo vinegar 

1. Bamboo charcoal has a dense structure with many pores, and hence has powerful absorption/attachment capability and can be used to regulate humidity level and to deodorize. Additionally, bamboo charcoal emits far-infrared radiation which is easily absorbed by the human body, improving blood circulation and general health . Bamboo charcoal is used in many everyday products , including washing agents, food additives, activated carbon and bamboo charcoal yarns. 

 

2. Bamboo vinegar has a smoky scent and is an acidic liquid, with a specific weight of about 1.01 and a pH value of 1.5~3.7 Over 90% of bamboo vinegar is water , while the remaining 10% consists of natural, structurally complicated compounds (mainly acetic acid). Bamboo vinegar can be used to deodorize and kill bacteria, and as a preservative. 

How bamboo is made into bamboo charcoal? 

(1) Selection of good bamboo 
To produce good quality bamboo charcoal, mature bamboo that is at least four years old should be chosen. After the bamboo is cut, it is dried until its water content is in the range of 15–18%, to ensure that the finished charcoal has a smooth surface. 

(2) Carbonization process 
The dried bamboo is placed in a conventional kiln or a mechanical furnace. If a conventional kiln is used, then the bamboo is burnt slowly with a small amount of air to ensure carbonization. Using a mechanical 

(3) Carbonization Temperature 
In the “preliminary carbonization process”, a temperature of 450–800°C is used. The carbonization temperature affects the structure, hardness, carbonization ratio, electrical resistance coefficient and functional radicals of the bamboo charcoal. In the “secondary carbonization process”, the temperature is maintained at 800–1200°C of temperature to enable the bamboo charcoal to realize certain special characteristics. 

(4) Carbonization devices 
Conventional kiln and mechanical furnace Two devices may be employed fabricate bamboo charcoal, a conventional kiln or a mechanical furnace. The physical and mechanical properties of finished bamboo charcoal depend on the device used and relevant manufacturing factors . 
The ITRI was entrusted by the Forestry Bureau Council of Agriculture to develop a multifunctional modular carbonization oven, which has all the advantages of both conventional kilns and mechanical furnaces, and is fueled by biomass energy. The new oven enables reuse of energy and improved carbonization and activation effects, thus enhancing the bamboo charcoal quality and the carbonization rate. 

Chemical composition of bamboo charcoal 

Bamboo charcoal mainly comprises chemicals containing carbon, hydrogen and oxygen. After carbonization, finished bamboo charcoal has a carbon content in the range 76%–85%. The following table shows the mineral element found in water which has been boiled with bamboo charcoal. 
�� Useful functions of bamboo charcoal 

(1) Strong absorption capability 
Bamboo charcoal is a natural, highly porous organic material. The average surface area of 1g of bamboo charcoal is about 300m2, while that of 1g of activated bamboo charcoal may even reachover 1,200m2 (about the size of a rugby field) . The pores are highly absorbant, and can regulate the humidity of the ambient air and the water content in soil: when the ambient humidity rises, they absorb water molecules, and when the ambient humidity drops, they release water molecules. Additionally, bamboo charcoal may be used as a filtering material (i.e., a biological carrier) to remove unwanted particles from water. 
Moreover , bamboo charcoal can easily absorb some airborne organic pollutants, such as sulphide, nitrides, methanol, benzenes, phenols and CH3Cl, and has strong deodorizing capabilities. 
(2) Far-infrared radiation emission 
Infrared radiation was discovered by a German scientist, Sir William Herschel, in around 1800. Infrared radiation is a class of electromagnetic radiations existing in the sun light, and can be divided into near-infrared radiation (0.75μm to 1.5μm), medium-infrared radiation (1.5μm to 5.6μm) and far-infrared radiation (5.6μm to 1000μm). 
Before 1970, far-infrared radiation was primarilyused in physics labs; after 1970, it gradually became common in medical and health-related applications. Bamboo charcoal emits far-infrared radiation, which is easily absorbed by the human body . According to Japanese medical reports , far-infrared radiation emitted from bamboo charcoal can cure radical malfunction caused by the gathering of the red blood cells in our blood, and therefore is good for blood circulation. 
(3) Shield against electromagnetic radiation 
Materials which conduct electricity or which have many pores may be employed as shields against electromagnetic radiation. Conducting materials can disrupt the propagation of electromagnetic waves; while porous materials can decrease the magnitude of electromagnetic radiation. 
Besides being very porous, bamboo charcoal has a high silicon content. Hence, bamboo charcoal from carbonization at above 800°C of has a high conductivity and can block out electromagnetic radiation in environment.